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On the Natural Faculties
By Galen


Translated by Arthur John Brock

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BOOK ONE

1. Since feeling and voluntary motion are peculiar to animals, whilst
growth and nutrition are common to plants as well, we may look on
the former as effects of the soul and the latter as effects of the
nature. And if there be anyone who allows a share in soul to plants
as well, and separates the two kinds of soul, naming the kind in question
vegetative, and the other sensory, this person is not saying anything
else, although his language is somewhat unusual. We, however, for
our part, are convinced that the chief merit of language is clearness,
and we know that nothing detracts so much from this as do unfamiliar
terms; accordingly we employ those terms which the bulk of people
are accustomed to use, and we say that animals are governed at once
by their soul and by their nature, and plants by their nature alone,
and that growth and nutrition are the effects of nature, not of soul.

2. Thus we shall enquire, in the course of this treatise, from what
faculties these effects themselves, as well as any other effects of
nature which there may be, take their origin. 

First, however, we must distinguish and explain clearly the various
terms which we are going to use in this treatise, and to what things
we apply them; and this will prove to be not merely an explanation
of terms but at the same time a demonstration of the effects of nature.

When, therefore, such and such a body undergoes no change from its
existing state, we say that it is at rest; but, not withstanding,
if it departs from this in any respect we then say that in this respect
it undergoes motion. Accordingly, when it departs in various ways
from its preexisting state, it will be said to undergo various kinds
of motion. Thus, if that which is white becomes black, or what is
black becomes white, it undergoes motion in respect to colour; or
if what was previously sweet now becomes bitter, or, conversely, from
being bitter now becomes sweet, it will be said to undergo motion
in respect to flavour; to both of these instances, as well as to those
previously mentioned, we shall apply the term qualitative motion.
And further, it is not only things which are altered in regard to
colour and flavour which, we say, undergo motion; when a warm thing
becomes cold, and a cold warm, here too we speak of its undergoing
motion; similarly also when anything moist becomes dry, or dry moist.
Now, the common term which we apply to all these cases is alteration.

This is one kind of motion. But there is another kind which occurs
in bodies which change their position, or as we say, pass from one
place to another; the name of this is transference. 

These two kinds of motion, then, are simple and primary, while compounded
from them we have growth and decay, as when a small thing becomes
bigger, or a big thing smaller, each retaining at the same time its
particular form. And two other kinds of motion are genesis and destruction,
genesis being a coming into existence, and destruction being the opposite.

Now, common to all kinds of motion is change from the preexisting
state, while common to all conditions of rest is retention of the
preexisting state. The Sophists, however, while allowing that bread
in turning into blood becomes changed as regards sight, taste, and
touch, will not agree that this change occurs in reality. Thus some
of them hold that all such phenomena are tricks and illusions of our
senses; the senses, they say, are affected now in one way, now in
another, whereas the underlying substance does not admit of any of
these changes to which the names are given. Others (such as Anaxagoras)
will have it that the qualities do exist in it, but that they are
unchangeable and immutable from eternity to eternity, and that these
apparent alterations are brought about by separation and combination.

Now, if I were to go out of my way to confute these people, my subsidiary
task would be greater than my main one. Thus, if they do not know
all that has been written, "On Complete Alteration of Substance" by
Aristotle, and after him by Chrysippus, I must beg of them to make
themselves familiar with these men's writings. If, however, they know
these, and yet willingly prefer the worse views to the better, they
will doubtless consider my arguments foolish also. I have shown elsewhere
that these opinions were shared by Hippocrates, who lived much earlier
than Aristotle. In fact, all those known to us who have been both
physicians and philosophers Hippocrates was the first who took in
hand to demonstrate that there are, in all, four mutually interacting
qualities, and that to the operation of these is due the genesis and
destruction of all things that come into and pass out of being. Nay,
more; Hippocrates was also the first to recognise that all these qualities
undergo an intimate mingling with one another; and at least the beginnings
of the proofs to which Aristotle later set his hand are to be found
first in the writings of Hippocrates. 

As to whether we are to suppose that the substances as well as their
qualities undergo this intimate mingling, as Zeno of Citium afterwards
declared, I do not think it necessary to go further into this question
in the present treatise; for immediate purposes we only need to recognize
the complete alteration of substance. In this way, nobody will suppose
that bread represents a kind of meeting-place for bone, flesh, nerve,
and all the other parts, and that each of these subsequently becomes
separated in the body and goes to join its own kind; before any separation
takes place, the whole of the bread obviously becomes blood; (at any
rate, if a man takes no other food for a prolonged period, he will
have blood enclosed in his veins all the same). And clearly this disproves
the view of those who consider the elements unchangeable, as also,
for that matter, does the oil which is entirely used up in the flame
of the lamp, or the faggots which, in a somewhat longer time, turn
into fire. 

I said, however, that I was not going to enter into an argument with
these people, and it was only because the example was drawn from the
subject-matter of medicine, and because I need it for the present
treatise, that I have mentioned it. We shall then, as I said, renounce
our controversy with them, since those who wish may get a good grasp
of the views of the ancients from our own personal investigations
into these matters. 

The discussion which follows we shall devote entirely, as we originally
proposed, to an enquiry into the number and character of the faculties
of Nature, and what is the effect which each naturally produces. Now,
of course, I mean by an effect that which has already come into existence
and has been completed by the activity of these faculties- for example,
blood, flesh, or nerve. And activity is the name I give to the active
change or motion, and the cause of this I call a faculty. Thus, when
food turns into blood, the motion of the food is passive, and that
of the vein active. Similarly, when the limbs have their position
their position altered, it is the muscle which produces, and the bones
which undergo the motion. In these cases I call the motion of the
vein and of the muscle an activity, and that of the food and the bones
a symptom or affection, since the first group undergoes alteration
and the second group is merely transported. One might, therefore,
also speak of the activity as an effect of Nature- for example, digestion,
absorption, blood-production; one could not, however, in every case
call the effect an activity; thus flesh is an effect of Nature, but
it is, of course, not an activity. It is, therefore, clear that one
of these terms is used in two senses, but not the other.

3. It appears to me, then, that the vein, as well as each of the other
parts, functions in such and such a way according to the manner in
which the four qualities are mixed. There are, however, a considerable
number of not undistinguished men- philosophers and physicians- who
refer action to the Warm and the Cold, and who subordinate to these,
as passive, the Dry and the Moist; Aristotle, in fact, was the first
who attempted to bring back the causes of the various special activities
to these principles, and he was followed later by the Stoic school.
These latter, of course, could logically make active principles of
the Warm and Cold, since they refer the change of the elements themselves
into one another to certain diffusions and condensations. This does
not hold of Aristotle, however; seeing that he employed the four qualities
to explain the genesis of the elements, he ought properly to have
also referred the causes of all the special activities to these. How
is it that he uses the four qualities in his book "On Genesis and
Destruction," whilst in his "Meteorology," his "Problems," and many
other works he uses the uses the two only? Of course, if anyone were
to maintain that in the case of animals and plants the Warm and Cold
are more active, the Dry and Moist less so, he might perhaps have
even Hippocrates on his side; but if he were to say that this happens
in all cases, he would, I imagine, lack support, not merely from Hippocrates,
but even from Aristotle himself- if, at least, Aristotle chose to
remember what he himself taught us in his work "On Genesis and Destruction,"
not as a matter of simple statement, but with an accompanying demonstration.
I have, however, also investigated these questions, in so far as they
are of value to a physician, in my work "On Temperaments."

4. The so-called blood-making faculty in the veins, then, as well
as all the other faculties, fall within the category of relative concepts;
primarily because the faculty is the cause of the activity, but also,
accidentally, because it is the cause of the effect. But, if the cause
is relative to something- for it is the cause of what results from
it, and of nothing else- it is obvious that the faculty also falls
into the category of the relative; and so long as we are ignorant
of the true essence of the cause which is operating, we call it a
faculty. Thus we say that there exists in the veins a blood-making
faculty, as also a digestive faculty in the stomach, a pulsatile faculty
in the heart, and in each of the other parts a special faculty corresponding
to the function or activity of that part. If, therefore, we are to
investigate methodically the number and kinds of faculties, we must
begin with the effects; for each of these effects comes from a certain
activity, and each of these again is preceded by a cause.

5. The effects of Nature, then, while the animal is still being formed
in the womb, are all the different parts of its body; and after it
has been born, an effect in which all parts share is the progress
of each to its full size, and thereafter its maintenance of itself
as long as possible. 

The activities corresponding to the three effects mentioned are necessarily
three- one to each- namely, Genesis, Growth, and Nutrition. Genesis,
however, is not a simple activity of Nature, but is compounded of
alteration and of shaping. That is to say, in order that bone, nerve,
veins, and all other [tissues] may come into existence, the underlying
substance from which the animal springs must be altered; and in order
that the substance so altered may acquire its appropriate shape and
position, its cavities, outgrowths, attachments, and so forth, it
has to undergo a shaping or formative process. One would be justified
in calling this substance which undergoes alteration the material
of the animal, just as wood is the material of a ship, and wax of
an image. 

Growth is an increase and expansion in length, breadth, and thickness
of the solid parts of the animal (those which have been subjected
to the moulding or shaping process). Nutrition is an addition to these,
without expansion. 

6. Let us speak then, in the first place, of Genesis, which, as we
have said, results from alteration together with shaping.

The seed having been cast into the womb or into the earth (for there
is no difference), then, after a certain definite period, a great
number of parts become constituted in the substance which is being
generated; these differ as regards moisture, dryness, coldness and
warmth, and in all the other qualities which naturally derive therefrom.
These derivative qualities, you are acquainted with, if you have given
any sort of scientific consideration to the question of genesis and
destruction. For, first and foremost after the qualities mentioned
come the other so-called tangible distinctions, and after them those
which appeal to taste, smell, and sight. Now, tangible distinctions
are hardness and softness, viscosity, friability, lightness, heaviness,
density, rarity, smoothness, roughness, thickness and thinness; all
of these have been duly mentioned by Aristotle. And of course you
know those which appeal to taste, smell, and sight. Therefore, if
you wish to know which alterative faculties are primary and elementary,
they are moisture, dryness, coldness, and warmth, and if you wish
to know which ones arise from the combination of these, they will
be found to be in each animal of a number corresponding to its sensible
elements. The name sensible elements is given to all the homogeneous
parts of the body, and these are to be detected not by any system,
but by personal observation of dissections. 

Now Nature constructs bone, cartilage, nerve, membrane, ligament,
vein, and so forth, at the first stage of the animal's genesis, employing
at this task a faculty which is, in general terms, generative and
alterative, and, in more detail, warming, chilling, drying, or moistening;
or such as spring from the blending of these, for example, the bone-producing,
nerve-producing, and cartilage-producing faculties (since for the
sake of clearness these names must be used as well). 

Now the peculiar flesh of the liver is of this kind as well, also
that of the spleen, that of the kidneys, that of the lungs, and that
of the heart; so also the proper substance of the brain, stomach,
gullet, intestines, and uterus is a sensible element, of similar parts
all through, simple, and uncompounded. That is to say, if you remove
from each of the organs mentioned its arteries, veins, and nerves,
the substance remaining in each organ is, from the point of view of
the senses, simple and elementary. As regards those organs consisting
of two dissimilar coats, of which each is simple, of these organs
the coats are the are the elements- for example, the coats of the
stomach, oesophagus, intestines, and arteries; each of these two coats
has an alterative faculty peculiar to it, which has engendered it
from the menstrual blood of the mother. Thus the special alterative
faculties in each animal are of the same number as the elementary
parts; and further, the activities must necessarily correspond each
to one of the special parts, just as each part has its special use-
for example, those ducts which extend from the kidneys into the bladder,
and which are called ureters; for these are not arteries, since they
do not pulsate nor do they consist of two coats; and they are not
veins, since they neither contain blood, nor do their coats in any
way resemble those of veins; from nerves they differ still more than
from the structures mentioned. 

"What, then, are they?" someone asks- as though every part must necessarily
be either an artery, a vein, a nerve, or a complex of these, and as
though the truth were not what I am now stating, namely, that every
one of the various organs has its own particular substance. For in
fact the two bladders- that which receives the urine, and that which
receives the yellow bile- not only differ from all other organs, but
also from one another. Further, the ducts which spring out like kinds
of conduits from the gall-bladder and which pass into the liver have
no resemblance either to arteries, veins or nerves. But these parts
have been treated at a greater length in my work "On the Anatomy of
Hippocrates," as well as elsewhere. 

As for the actual substance of the coats of the stomach, intestine,
and uterus, each of these has been rendered what it is by a special
alterative faculty of Nature; while the bringing of these together,
the therewith of the structures which are inserted into them, the
outgrowth into the intestine, the shape of the inner cavities, and
the like, have all been determined by a faculty which we call the
shaping or formative faculty; this faculty we also state to be artistic-
nay, the best and highest art- doing everything for some purpose,
so that there is nothing ineffective or superfluous, or capable of
being better disposed. This, however, I shall demonstrate in my work
"On the Use of Parts." 

7. Passing now to the faculty of Growth let us first mention that
this, too, is present in the foetus in utero as is also the nutritive
faculty, but that at that stage these two faculties are, as it were,
handmaids to those already mentioned, and do not possess in themselves
supreme authority. When, however, the animal has attained its complete
size, then, during the whole period following its birth and until
the acme is reached, the faculty of growth is predominant, while the
alterative and nutritive faculties are accessory- in fact, act as
its handmaids. What, then, is the property of this faculty of growth?
To extend in every direction that which has already come into existence-
that is to say, the solid parts of the body, the arteries, veins,
nerves, bones, cartilages, membranes, ligaments, and the various coats
which we have just called elementary, homogeneous, and simple. And
I shall state in what way they gain this extension in every direction,
first giving an illustration for the sake of clearness. 

Children take the bladders of pigs, fill them with air, and then rub
them on ashes near the fire, so as to warm, but not to injure them.
This is a common game in the district of Ionia, and among not a few
other nations. As they rub, they sing songs, to a certain measure,
time, and rhythm, and all their words are an exhortation to the bladder
to increase in size. When it appears to them fairly well distended,
they again blow air into it and expand it further; then they rub it
again. This they do several times, until the bladder seems to them
to have become large enough. Now, clearly, in these doings of the
children, the more the interior cavity of the bladder increases in
size, the thinner, necessarily, does its substance become. But, if
the children were able to bring nourishment to this thin part, then
they would make the bladder big in the same way that Nature does.
As it is, however, they cannot do what Nature does, for to imitate
this is beyond the power not only of children, but of any one soever;
it is a property of Nature alone. 

It will now, therefore, be clear to you that nutrition is a necessity
for growing things. For if such bodies were distended, but not at
the same time nourished, they would take on a false appearance of
growth, not a true growth. And further, to be distended in all directions
belongs only to bodies whose growth is directed by Nature; for those
which are distended by us undergo this distension in one direction
but grow less in the others; it is impossible to find a body which
will remain entire and not be torn through whilst we stretch it in
the three dimensions. Thus Nature alone has the power to expand a
body in all directions so that it remains unruptured and preserves
completely its previous form. 

Such then is growth, and it cannot occur without the nutriment which
flows to the part and is worked up into it. 

8. We have, then, it seems, arrived at the subject of Nutrition, which
is the third and remaining consideration which we proposed at the
outset. For, when the matter which flows to each part of the body
in the form of nutriment is being worked up into it, this activity
is nutrition, and its cause is the nutritive faculty. Of course, the
kind of activity here involved is also an alteration, but not an alteration
like that occurring at the stage of genesis. For in the latter case
something comes into existence which did not exist previously, while
in nutrition the inflowing material becomes assimilated to that which
has already come into existence. Therefore, the former kind of alteration
has with reason been termed genesis, and the latter, assimilation.

9. Now, since the three faculties of Nature have been exhaustively
dealt with, and the animal would appear not to need any others (being
possessed of the means for growing, for attaining completion, and
for maintaining itself as long a time as possible), this treatise
might seem to be already complete, and to constitute an exposition
of all the faculties of Nature. If, however, one considers that it
has not yet touched upon any of the parts of the animal (I mean the
stomach, intestines, liver, and the like), and that it has not dealt
with the faculties resident in these, it will seem as though merely
a kind of introduction had been given to the practical parts of our
teaching. For the whole matter is as follows: Genesis, growth, and
nutrition are the first, and, so to say, the principal effects of
Nature; similarly also the faculties which produce these effects-
the first faculties- are three in number, and are the most dominating
of all. But as has already been shown, these need the service both
of each other, and of yet different faculties. Now, these which the
faculties of generation and growth require have been stated. I shall
now say what ones the nutritive faculty requires. 

10. For I believe that I shall prove that the organs which have to
do with the disposal of the nutriment, as also their faculties, exist
for the sake of this nutritive faculty. For since the action of this
faculty is assimilation, and it is impossible for anything to be assimilated
by, and to change into anything else unless they already possess a
certain community and affinity in their qualities, therefore, in the
first place, any animal cannot naturally derive nourishment from any
kind of food, and secondly, even in the case of those from which it
can do so, it cannot do this at once. Therefore, by reason of this
law, every animal needs several organs for altering the nutriment.
For in order that the yellow may become red, and the red yellow, one
simple process of alteration is required, but in order that the white
may become black, and the black white, all the intermediate stages
are needed. So also, a thing which is very soft cannot all at once
become very hard, nor vice versa; nor, similarly can anything which
has a very bad smell suddenly become quite fragrant, nor again, can
the converse happen. 

How, then, could blood ever turn into bone, without having first become,
as far as possible, thickened and white? And how could bread turn
into blood without having gradually parted with its whiteness and
gradually acquired redness? Thus it is quite easy for blood to become
flesh; for, if Nature thicken it to such an extent that it acquires
a certain consistency and ceases to be fluid, it thus becomes original
newly-formed flesh; but in order that blood may turn into bone, much
time is needed and much elaboration and transformation of the blood.
Further, it is quite clear that bread, and, more particularly lettuce,
beet, and the like, require a great deal of alteration, in order to
become blood. 

This, then, is one reason why there are so many organs concerned in
the alteration of food. A second reason is the nature of the superfluities.
For, as we are unable to draw any nourishment from grass, although
this is possible for cattle, similarly we can derive nourishment from
radishes, albeit not to the same extent as from meat; for almost the
whole of the latter is mastered by our natures; it is transformed
and altered and constituted useful blood; but, not withstanding, in
the radish, what is appropriate and capable of being altered (and
that only with difficulty, and with much labour) is the very smallest
part; almost the whole of it is surplus matter, and passes through
the digestive organs, only a very little being taken up into the veins
as blood- nor is this itself entirely utilisable blood. Nature, therefore,
had need of a second process of separation for the superfluities in
the veins. Moreover, these superfluities need, on the one hand, certain
fresh routes to conduct them to the outlets, so that they may not
spoil the useful substances, and they also need certain reservoirs,
as it were, in which they are collected till they reach a sufficient
quantity, and are then discharged. 

Thus, then, you have discovered bodily parts of a second kind, consecrated
in this case to the [removal of the] superfluities of the food. There
is, however, also a third kind, for carrying the pabulum in every
direction; these are like a number of roads intersecting the whole
body. 

Thus there is one entrance- that through the mouth- for all the various
articles of food. What receives nourishment, however, is not one single
part, but a great many parts, and these widely separated; do not be
surprised, therefore, at the abundance of organs which Nature has
created for the purpose of nutrition. For those of them which have
to do with alteration prepare the nutriment suitable for each part;
others separate out the superfluities; some pass these along, others
store them up, others excrete them; some, again, are paths for the
transit in all directions of the utilisable juices. So, if you wish
to gain a thorough acquaintance with all the faculties of Nature,
you will have consider each one of these organs. 

Now in giving an account of these we must begin with those effects
of Nature, together with their corresponding parts and faculties,
which are closely connected with the purpose to be achieved.

11. Let us once more, then, recall the actual purpose for which Nature
has constructed all these parts. Its name, as previously stated, is
nutrition, and the definition corresponding to the name is: an assimilation
of that which nourishes to that which receives nourishment. And in
order that this may come about, we must assume a preliminary process
of adhesion, and for that, again, one of presentation. For whenever
the juice which is destined to nourish any of the parts of the animal
is emitted from the vessels, it is in the first place dispersed all
through this part, next it is presented, and next it adheres, and
becomes completely assimilated. 

The so-called white [leprosy] shows the difference between assimilation
and adhesion, in the same way that the kind of dropsy which some people
call anasarca clearly distinguishes presentation from adhesion. For,
of course, the genesis of such a dropsy does not come about as do
some of the conditions of atrophy and wasting, from an insufficient
supply of moisture; the flesh is obviously moist enough,- in fact
it is thoroughly saturated,- and each of the solid parts of the body
is in a similar condition. While, however, the nutriment conveyed
to the part does undergo presentation, it is still too watery, and
is not properly transformed into a juice, nor has it acquired that
viscous and agglutinative quality which results from the operation
of innate heat; therefore, adhesion cannot come about, since, owing
to this abundance of thin, crude liquid, the pabulum runs off and
easily slips away from the solid parts of the body. In white [leprosy],
again, there is adhesion of the nutriment but no real assimilation.
From this it is clear that what I have just said is correct, namely,
that in that part which is to be nourished there must first occur
presentation, next adhesion, and finally assimilation proper.

Strictly speaking, then, nutriment is that which is actually nourishing,
while the quasi-nutriment which is not yet nourishing (e.g. matter
which is undergoing adhesion or presentation) is not, strictly speaking,
nutriment, but is so called only by an equivocation. Also, that which
is still contained in the veins, and still more, that which is in
the stomach, from the fact that it is destined to nourish if properly
elaborated, has been called "nutriment." Similarly we call the various
kinds of food "nutriment," not because they are already nourishing
the animal, nor because they exist in the same state as the material
which actually is nourishing it, but because they are able and destined
to nourish it if they be properly elaborated. 

This was also what Hippocrates said, viz., "Nutriment is what is engaged
in nourishing, as also is quasi-nutriment, and what is destined to
be nutriment." For to that which is already being assimilated he gave
the name of nutriment; to the similar material which is being presented
or becoming adherent, the name of quasi-nutriment; and to everything
else- that is, contained in the stomach and veins- the name of destined
nutriment. 

12. It is quite clear, therefore, that nutrition must necessarily
be a process of assimilation of that which is nourishing to that which
is being nourished. Some, however, say that this assimilation does
not occur in reality, but is merely apparent; these are the people
who think that Nature is not artistic, that she does not show forethought
for the animal's welfare, and that she has absolutely no native powers
whereby she alters some substances, attracts others, and discharges
others. 

Now, speaking generally, there have arisen the following two sects
in medicine and philosophy among those who have made any definite
pronouncement regarding Nature. I speak, of course, of such of them
as know what they are talking about, and who realize the logical sequence
of their hypotheses, and stand by them; as for those who cannot understand
even this, but who simply talk any nonsense that comes to their tongues,
and who do not remain definitely attached either to one sect or the
other- such people are not even worth mentioning. 

What, then, are these sects, and what are the logical consequences
of their hypotheses? The one class supposes that all substance which
is subject to genesis and destruction is at once continuous and susceptible
of alteration. The other school assumes substance to be unchangeable,
unalterable, and subdivided into fine particles, which are separated
from one another by empty spaces. 

All people, therefore, who can appreciate the logical sequence of
an hypothesis hold that, according to the second teaching, there does
not exist any substance or faculty peculiar either to Nature or to
Soul, but that these result from the way in which the primary corpuscles,
which are unaffected by change, come together. According to the first-mentioned
teaching, on the other hand, Nature is not posterior to the corpuscles,
but is a long way prior to them and older than they; and therefore
in their view it is Nature which puts together the bodies both of
plants and animals; and this she does by virtue of certain faculties
which she possesses- these being, on the one hand, attractive and
assimilative of what is appropriate, and, on the other, of what is
foreign. Further, she skilfully moulds everything during the stage
of genesis; and she also provides for the creatures after birth, employing
here other faculties again, namely, one of affection and forethought
for offspring, and one of sociability and friendship for kindred.
According to the other school, none of these things exist in the natures
[of living things], nor is there in the soul any original innate idea,
whether of agreement or difference, of separation or synthesis, of
justice or injustice, of the beautiful or ugly; all such things, they
say, arise in us from sensation and through sensation, and animals
are steered by certain images and memories. 

Some of these people have even expressly declared that the soul possesses
no reasoning faculty, but that we are led like cattle by the impression
of our senses, and are unable to refuse or dissent from anything.
In their view, obviously, courage, wisdom, temperance, and self-control
are all mere nonsense, we do not love either each other or our offspring,
nor do the gods care anything for us. This school also despises dreams,
birds, omens, and the whole of astrology, subjects with which we have
dealt at greater length in another work, in which we discuss the views
of Asclepiades the physician. Those who wish to do so may familiarize
themselves with these arguments, and they may also consider at this
point which of the two roads lying before us is the better one to
take. Hippocrates took the first-mentioned. According to this teaching,
substance is one and is subject to alteration; there is a consensus
in the movements of air and fluid throughout the whole body; Nature
acts throughout in an artistic and equitable manner, having certain
faculties, by virtue of which each part of the body draws to itself
the juice which is proper to it, and, having done so, attaches it
to every portion of itself, and completely assimilates it; while such
part of the juice as has not been mastered, and is not capable of
undergoing complete alteration and being assimilated to the part which
is being nourished, is got rid of by yet another (an expulsive) faculty.

13. Now the extent of exactitude and truth in the doctrines of Hippocrates
may be gauged, not merely from the way in which his opponents are
at variance with obvious facts, but also from the various subjects
of natural research themselves- the functions of animals, and the
rest. For those people who do not believe that there exists in any
part of the animal a faculty for attracting its own special quality
are compelled repeatedly to deny obvious facts. For instance, Asclepiades,
the physician, did this in the case of the kidneys. That these are
organs for secreting [separating out] the urine, was the belief not
only of Hippocrates, Diocles, Erasistratus, Praxagoras, and all other
physicians of eminence, but practically every butcher is aware of
this, from the fact that he daily observes both the position of the
kidneys and the duct (termed the ureter) which runs from each kidney
into the bladder, and from this arrangement he infers their characteristic
use and faculty. But, even leaving the butchers aside, all people
who suffer either from frequent dysuria or from retention of urine
call themselves "nephritics," when they feel pain in the loins and
pass sandy matter in their water. 

I do not suppose that Asclepiades ever saw a stone which had been
passed by one of these sufferers, or observed that this was preceded
by a sharp pain in the region between kidneys and bladder as the stone
traversed the ureter, or that, when the stone was passed, both the
pain and the retention at once ceased. It is worth while, then, learning
how his theory accounts for the presence of urine in the bladder,
and one is forced to marvel at the ingenuity of a man who puts aside
these broad, clearly visible routes, and postulates others which are
narrow, invisible- indeed, entirely imperceptible. His view, in fact,
is that the fluid which we drink passes into the bladder by being
resolved into vapours, and that, when these have been again condensed,
it thus regains its previous form, and turns from vapour into fluid.
He simply looks upon the bladder as a sponge or a piece of wool, and
not as the perfectly compact and impervious body that it is, with
two very strong coats. For if we say that the vapours pass through
these coats, why should they not pass through the peritoneum and the
diaphragm, thus filling the whole abdominal cavity and thorax with
water? "But," says he, "of course the peritoneal coat is more impervious
than the bladder, and this is why it keeps out the vapours, while
the bladder admits them." Yet if he had ever practised anatomy, he
might have known that the outer coat of the bladder springs from the
peritoneum and is essentially the same as it, and that the inner coat,
which is peculiar to the bladder, is more than twice as thick as the
former. 

Perhaps, however, it is not the thickness or thinness of the coats,
but the situation of the bladder, which is the reason for the vapours
being carried into it? On the contrary, even if it were probable for
every other reason that the vapours accumulate there, yet the situation
of the bladder would be enough in itself to prevent this. For the
bladder is situated below, whereas vapours have a natural tendency
to rise upwards; thus they would fill all the region of the thorax
and lungs long before they came to the bladder. 

But why do I mention the situation of the bladder, peritoneum, and
thorax? For surely, when the vapours have passed through the coats
of the stomach and intestines, it is in the space between these and
the peritoneum that they will collect and become liquefied (just as
in dropsical subjects it is in this region that most of the water
gathers). Otherwise the vapours must necessarily pass straight forward
through everything which in any way comes in contact with them, and
will never come to a standstill. But, if this be assumed, then they
will traverse not merely the peritoneum but also the epigastrium,
and will become dispersed into the surrounding air; otherwise they
will certainly collect under the skin. 

Even these considerations, however, our present-day Asclepiadeans
attempt to answer, despite the fact that they always get soundly laughed
at by all who happen to be present at their disputations on these
subjects- so difficult an evil to get rid of is this sectarian partizanship,
so excessively resistant to all cleansing processes, harder to heal
than any itch! 

Thus, one of our Sophists who is a thoroughly hardened disputer and
as skilful a master of language as there ever was, once got into a
discussion with me on this subject; so far from being put out of countenance
by any of the above-mentioned considerations, he even expressed his
surprise that I should try to overturn obvious facts by ridiculous
arguments! "For," said he, "one may clearly observe any day in the
case of any bladder, that, if one fills it with water or air and then
ties up its neck and squeezes it all round, it does not let anything
out at any point, but accurately retains all its contents. And surely,"
said he, "if there were any large and perceptible channels coming
into it from the kidneys the liquid would run out through these when
the bladder was squeezed, in the same way that it entered?" Having
abruptly made these and similar remarks in precise and clear tones,
he concluded by jumping up and departing- leaving me as though I were
quite incapable of finding any plausible answer! 

The fact is that those who are enslaved to their sects are not merely
devoid of all sound knowledge, but they will not even stop to learn!
Instead of listening, as they ought, to the reason why liquid can
enter the bladder through the ureters, but is unable to go back again
the same way,- instead of admiring Nature's artistic skill- they refuse
to learn; they even go so far as to scoff, and maintain that the kidneys,
as well as many other things, have been made by Nature for no purpose!
And some of them who had allowed themselves to be shown the ureters
coming from the kidneys and becoming implanted in the bladder, even
had the audacity to say that these also existed for no purpose; and
others said that they were spermatic ducts, and that this was why
they were inserted into the neck of the bladder and not into its cavity.
When, therefore, we had demonstrated to them the real spermatic ducts
entering the neck of the bladder lower down than the ureters, we supposed
that, if we had not done so before, we would now at least draw them
away from their false assumptions, and convert them forthwith to the
opposite view. But even this they presumed to dispute, and said that
it was not to be wondered at that the semen should remain longer in
these latter ducts, these being more constricted, and that it should
flow quickly down the ducts which came from the kidneys, seeing that
these were well dilated. We were, therefore, further compelled to
show them in a still living animal, the urine plainly running out
through the ureters into the bladder; even thus we hardly hoped to
check their nonsensical talk. 

Now the method of demonstration is as follows. One has to divide the
peritoneum in front of the ureters, then secure these with ligatures,
and next, having bandaged up the animal, let him go (for he will not
continue to urinate). After this one loosens the external bandages
and shows the bladder empty and the ureters quite full and distended-
in fact almost on the point of rupturing; on removing the ligature
from them, one then plainly sees the bladder becoming filled with
urine. 

When this has been made quite clear, then, before the animal urinates,
one has to tie a ligature round his penis and then to squeeze the
bladder all over; still nothing goes back through the ureters to the
kidneys. Here, then, it becomes obvious that not only in a dead animal,
but in one which is still living, the ureters are prevented from receiving
back the urine from the bladder. These observations having been made,
one now loosens the ligature from the animal's penis and allows him
to urinate, then again ligatures one of the ureters and leaves the
other to discharge into the bladder. Allowing, then, some time to
elapse, one now demonstrates that the ureter which was ligatured is
obviously full and distended on the side next to the kidneys, while
the other one- that from which the ligature had been taken- is itself
flaccid, but has filled the bladder with urine. Then, again, one must
divide the full ureter, and demonstrate how the urine spurts out of
it, like blood in the operation of vene-section; and after this one
cuts through the other also, and both being thus divided, one bandages
up the animal externally. Then when enough time seems to have elapsed,
one takes off the bandages; the bladder will now be found empty, and
the whole region between the intestines and the peritoneum full of
urine, as if the animal were suffering from dropsy. Now, if anyone
will but test this for himself on an animal, I think he will strongly
condemn the rashness of Asclepiades, and if he also learns the reason
why nothing regurgitates from the bladder into the ureters, I think
he will be persuaded by this also of the forethought and art shown
by Nature in relation to animals. 

Now Hippocrates, who was the first known to us of all those who have
been both physicians and philosophers in as much as he was the first
to recognize what Nature effects, expresses his admiration of her,
and is constantly singing her praises and calling her "just." Alone,
he says, she suffices for the animal in every respect, performing
of her own accord and without any teaching all that is required. Being
such, she has, as he supposes, certain faculties, one attractive of
what is appropriate, and another eliminative of what is foreign, and
she nourishes the animal, makes it grow, and expels its diseases by
crisis. Therefore he says that there is in our bodies a concordance
in the movements of air and fluid, and that everything is in sympathy.
According to Asclepiades, however, nothing is naturally in sympathy
with anything else, all substance being divided and broken up into
inharmonious elements and absurd "molecules." Necessarily, then, besides
making countless other statements in opposition to plain fact, he
was ignorant of Nature's faculties, both that attracting what is appropriate,
and that expelling what is foreign. Thus he invented some wretched
nonsense to explain blood-production and anadosis, and, being utterly
unable to find anything to say regarding the clearing-out of superfluities,
he did not hesitate to join issue with obvious facts, and, in this
matter of urinary secretion, to deprive both the kidneys and the ureters
of their activity, by assuming that there were certain invisible channels
opening into the bladder. It was, of course, a grand and impressive
thing to do, to mistrust the obvious, and to pin one's faith in things
which could not be seen! 

Also, in the matter of the yellow bile, he makes an even grander and
more spirited venture; for he says this is actually generated in the
bile-ducts, not merely separated out. 

How comes it, then, that in cases of jaundice two things happen at
the same time- that the dejections contain absolutely no bile, and
that the whole body becomes full of it? He is forced here again to
talk nonsense, just as he did in regard to the urine. He also talks
no less nonsense about the black bile and the spleen, not understanding
what was said by Hippocrates; and he attempts in stupid- I might say
insane- language, to contradict what he knows nothing about.

And what profit did he derive from these opinions from the point of
view of treatment? He neither was able to cure a kidney ailment, nor
jaundice, nor a disease of black bile, nor would he agree with the
view held not merely by Hippocrates but by all men regarding drugs-
that some of them purge away yellow bile, and others black, some again
phlegm, and others the thin and watery superfluity; he held that all
the substances evacuated were produced by the drugs themselves, just
as yellow bile is produced by the biliary passages! It matters nothing,
according to this extraordinary man, whether we give a hydragogue
or a cholagogue in a case of dropsy, for these all equally purge and
dissolve the body, and produce a solution having such and such an
appearance, which did not exist as such before! 

Must we not, therefore, suppose he was either mad, or entirely unacquainted
with practical medicine? For who does not know that if a drug for
attracting phlegm be given in a case of jaundice it will not even
evacuate four cyathi of phlegm? Similarly also if one of the hydragogues
be given. A cholagogue, on the other hand, clears away a great quantity
of bile, and the skin of patients so treated at once becomes clear.
I myself have, in many cases, after treating the liver condition,
then removed the disease by means of a single purgation; whereas,
if one had employed a drug for removing phlegm one would have done
no good. 

Nor is Hippocrates the only one who knows this to be so, whilst those
who take experience alone as their starting-point know otherwise;
they, as well as all physicians who are engaged in the practice of
medicine, are of this opinion. Asclepiades, however, is an exception;
he would hold it a betrayal of his assumed "elements" to confess the
truth about such matters. For if a single drug were to be discovered
which attracted such and such a humour only, there would obviously
be danger of the opinion gaining ground that there is in every body
a faculty which attracts its own particular quality. He therefore
says that safflower, the Cnidian berry, and Hippophaes, do not draw
phlegm from the body, but actually make it. Moreover, he holds that
the flower and scales of bronze, and burnt bronze itself, and germander,
and wild mastich dissolve the body into water, and that dropsical
patients derive benefit from these substances, not because they are
purged by them, but because they are rid of substances which actually
help to increase the disease; for, if the medicine does not evacuate
the dropsical fluid contained in the body, but generates it, it aggravates
the condition further. Moreover, scammony, according to the Asclepiadean
argument, not only fails to evacuate the bile from the bodies of jaundiced
subjects, but actually turns the useful blood into bile, and dissolves
the body; in fact it does all manner of evil and increases the disease.

And yet this drug may be clearly seen to do good to numbers of people!
"Yes," says he, "they derive benefit certainly, but merely in proportion
to the evacuation."... But if you give these cases a drug which draws
off phlegm they will not be benefited. This is so obvious that even
those who make experience alone their starting-point are aware of
it; and these people make it a cardinal point of their teaching to
trust to no arguments, but only to what can be clearly seen. In this,
then, they show good sense; whereas Asclepiades goes far astray in
bidding us distrust our senses where obvious facts plainly overturn
his hypotheses. Much better would it have been for him not to assail
obvious facts, but rather to devote himself entirely to these.

Is it, then, these facts only which are plainly irreconcilable with
the views of Asclepiades? Is not also the fact that in summer yellow
bile is evacuated in greater quantity by the same drugs, and in winter
phlegm, and that in a young man more bile is evacuated, and in an
old man more phlegm? Obviously each drug attracts something which
already exists, and does not generate something previously non-existent.
Thus if you give in the summer season a drug which attracts phlegm
to a young man of a lean and warm habit, who has lived neither idly
nor too luxuriously, you will with great difficulty evacuate a very
small quantity of this humour, and you will do the man the utmost
harm. On the other hand, if you give him a cholagogue, you will produce
an abundant evacuation and not injure him at all. 

Do we still, then, disbelieve that each drug attracts that humour
which is proper to it? Possibly the adherents of Asclepiades will
assent to this- or rather, they will- not possibly, but certainly-
declare that they disbelieve it, lest they should betray their darling
prejudices. 

14. Let us pass on, then, again to another piece of nonsense; for
the sophists do not allow one to engage in enquiries that are of any
worth, albeit there are many such; they compel one to spend one's
time in dissipating the fallacious arguments which they bring forward.

What, then, is this piece of nonsense? It has to do with the famous
and far-renowned stone which draws iron [the lodestone]. It might
be thought that this would draw their minds to a belief that there
are in all bodies certain faculties by which they attract their own
proper qualities. 

Now Epicurus, despite the fact that he employs in his "Physics" elements
similar to those of Asclepiades, yet allows that iron is attracted
by the lodestone, and chaff by amber. He even tries to give the cause
of the phenomenon. His view is that the atoms which flow from the
stone are related in shape to those flowing from the iron, and so
they become easily interlocked with one another; thus it is that,
after colliding with each of the two compact masses (the stone and
the iron) they then rebound into the middle and so become entangled
with each other, and draw the iron after them. So far, then, as his
hypotheses regarding causation go, he is perfectly unconvincing; nevertheless,
he does grant that there is an attraction. Further, he says that it
is on similar principles that there occur in the bodies of animals
the dispersal of nutriment and the discharge of waste matters, as
also the actions of cathartic drugs. 

Asclepiades, however, who viewed with suspicion the incredible character
of the cause mentioned, and who saw no other credible cause on the
basis of his supposed elements, shamelessly had recourse to the statement
that nothing is in any way attracted by anything else. Now, if he
was dissatisfied with what Epicurus said, and had nothing better to
say himself, he ought to have refrained from making hypotheses, and
should have said that Nature is a constructive artist and that the
substance of things is always tending towards unity and also towards
alteration because its own parts act upon and are acted upon by one
another. For, if he had assumed this, it would not have been difficult
to allow that this constructive Nature has powers which attract appropriate
and expel alien matter. For in no other way could she be constructive,
preservative of the animal, and eliminative of its diseases, unless
it be allowed that she conserves what is appropriate and discharges
what is foreign. 

But in this matter, too, Asclepiades realized the logical sequence
of the principles he had assumed; he showed no scruples, however,
in opposing plain fact; he joins issue in this matter also, not merely
with all physicians, but with everyone else, and maintains that there
is no such thing as a crisis, or critical day, and that Nature does
absolutely nothing for the preservation of the animal. For his constant
aim is to follow out logical consequences and to upset obvious fact,
in this respect being opposed to Epicurus; for the latter always stated
the observed fact, although he gives an ineffective explanation of
it. For, that these small corpuscles belonging to the lodestone rebound,
and become entangled with other similar particles of the iron, and
that then, by means of this entanglement (which cannot be seen anywhere)
such a heavy substance as iron is attracted- I fail to understand
how anybody could believe this. Even if we admit this, the same principle
will not explain the fact that, when the iron has another piece brought
in contact with it, this becomes attached to it. 

For what are we to say? That, forsooth, some of the particles that
flow from the lodestone collide with the iron and then rebound back,
and that it is by these that the iron becomes suspended? that others
penetrate into it, and rapidly pass through it by way of its empty
channels? that these then collide with the second piece of iron and
are not able to penetrate it although they penetrated the first piece?
and that they then course back to the first piece, and produce entanglements
like the former ones? 

The hypothesis here becomes clearly refuted by its absurdity. As a
matter of fact, I have seen five writing-stylets of iron attached
to one another in a line, only the first one being in contact with
the lodestone, and the power being transmitted through it to the others.
Moreover, it cannot be said that if you bring a second stylet into
contact with the lower end of the first, it becomes held, attached,
and suspended, whereas, if you apply it to any other part of the side
it does not become attached. For the power of the lodestone is distributed
in all directions; it merely needs to be in contact with the first
stylet at any point; from this stylet again the power flows, as quick
as a thought, all through the second, and from that again to the third.
Now, if you imagine a small lodestone hanging in a house, and in contact
with it all round a large number of pieces of iron, from them again
others, from these others, and so on,- all these pieces of iron must
surely become filled with the corpuscles which emanate from the stone;
therefore, this first little stone is likely to become dissipated
by disintegrating into these emanations. Further, even if there be
no iron in contact with it, it still disperses into the air, particularly
if this be also warm. 

"Yes," says Epicurus, "but these corpuscles must be looked on as exceedingly
small, so that some of them are a ten-thousandth part of the size
of the very smallest particles carried in the air." Then do you venture
to say that so great a weight of iron can be suspended by such small
bodies? If each of them is a ten-thousandth part as large as the dust
particles which are borne in the atmosphere, how big must we suppose
the hook-like extremities by which they interlock with each other
to be? For of course this is quite the smallest portion of the whole
particle. 

Then, again, when a small body becomes entangled with another small
body, or when a body in motion becomes entangled with another also
in motion, they do not rebound at once. For, further, there will of
course be others which break in upon them from above, from below,
from front and rear, from right and left, and which shake and agitate
them and never let them rest. Moreover, we must perforce suppose that
each of these small bodies has a large number of these hook-like extremities.
For by one it attaches itself to its neighbours, by another- the topmost
one- to the lodestone, and by the bottom one to the iron. For if it
were attached to the stone above and not interlocked with the iron
below, this would be of no use. Thus, the upper part of the superior
extremity must hang from the lodestone, and the iron must be attached
to the lower end of the inferior extremity; and, since they interlock
with each other by their sides as well, they must, of course, have
hooks there too. Keep in mind also, above everything, what small bodies
these are which possess all these different kinds of outgrowths. Still
more, remember how, in order that the second piece of iron may become
attached to the first, the third to the second, and to that the fourth,
these absurd little particles must both penetrate the passages in
the first piece of iron and at the same time rebound from the piece
coming next in the series, although this second piece is naturally
in every way similar to the first. 

Such an hypothesis, once again, is certainly not lacking in audacity;
in fact, to tell the truth, it is far more shameless than the previous
ones; according to it, when five similar pieces of iron are arranged
in a line, the particles of the lodestone which easily traverse the
first piece of iron rebound from the second, and do not pass readily
through it in the same way. Indeed, it is nonsense, whichever alternative
is adopted. For, if they do rebound, how then do they pass through
into the third piece? And if they do not rebound, how does the second
piece become suspended to the first? For Epicurus himself looked on
the rebound as the active agent in attraction. 

But, as I have said, one is driven to talk nonsense whenever one gets
into discussion with such men. Having, therefore, given a concise
and summary statement of the matter, I wish to be done with it. For
if one diligently familiarizes oneself with the writings of Asclepiades,
one will see clearly their logical dependence on his first principles,
but also their disagreement with observed facts. Thus, Epicurus, in
his desire to adhere to the facts, cuts an awkward figure by aspiring
to show that these agree with his principles, whereas Asclepiades
safeguards the sequence of principles, but pays no attention to the
obvious fact. Whoever, therefore, wishes to expose the absurdity of
their hypotheses, must, if the argument be in answer to Asclepiades,
keep in mind his disagreement with observed fact; or if in answer
to Epicurus, his discordance with his principles. Almost all the other
sects depending on similar principles are now entirely extinct, while
these alone maintain a respectable existence still. Yet the tenets
of Asclepiades have been unanswerably confuted by Menodotus the Empiricist,
who draws his attention to their opposition to phenomena and to each
other; and, again, those of Epicurus have been confuted by Asclepiades,
who adhered always to logical sequence, about which Epicurus evidently
cares little. 

Now people of the present day do not begin by getting a clear comprehension
of these sects, as well as of the better ones, thereafter devoting
a long time to judging and testing the true and false in each of them;
despite their ignorance, they style themselves, some "physicians"
and others "philosophers." No wonder, then, that they honour the false
equally with the true. For everyone becomes like the first teacher
that he comes across, without waiting to learn anything from anybody
else. And there are some of them, who, even if they meet with more
than one teacher, are yet so unintelligent and slow-witted that even
by the time they have reached old age they are still incapable of
understanding the steps of an argument.... In the old days such people
used to be set to menial tasks.... What will be the end of it God
knows! 

Now, we usually refrain from arguing with people whose principles
are wrong from the outset. Still, having been compelled by the natural
course of events to enter into some kind of a discussion with them,
we must add this further to what was said- that it is not only cathartic
drugs which naturally attract their special qualities, but also those
which remove thorns and the points of arrows such as sometimes become
deeply embedded in the flesh. Those drugs also which draw out animal
poisons or poisons applied to arrows all show the same faculty as
does the lodestone. Thus, I myself have seen a thorn which was embedded
in a young man's foot fail to come out when we exerted forcible traction
with our fingers, and yet come away painlessly and rapidly on the
application of a medicament. Yet even to this some people will object,
asserting that when the inflammation is dispersed from the part the
thorn comes away of itself, without being pulled out by anything.
But these people seem, in the first place, to be unaware that there
are certain drugs for drawing out inflammation and different ones
for drawing out embedded substances; and surely if it was on the cessation
of an inflammation that the abnormal matters were expelled, then all
drugs which disperse inflammations ought ipso facto; to possess the
power of extracting these substances as well. 

And secondly, these people seem to be unaware of a still more surprising
fact, namely, that not merely do certain medicaments draw out thorns
and others poisons, but that of the latter there are some which attract
the poison of the viper, others that of the sting-ray, and others
that of some other animal; we can, in fact, plainly observe these
poisons deposited on the medicaments. Here, then, we must praise Epicurus
for the respect he shows towards obvious facts, but find fault with
his views as to causation. For how can it be otherwise than extremely
foolish to suppose that a thorn which we failed to remove by digital
traction could be drawn out by these minute particles? 

Have we now, therefore, convinced ourselves that everything which
exists possesses a faculty by which it attracts its proper quality,
and that some things do this more, and some less? 

Or shall we also furnish our argument with the illustration afforded
by corn? For those who refuse to admit that anything is attracted
by anything else, will, I imagine, be here proved more ignorant regarding
Nature than the very peasants. When, for my own part, I first learned
of what happens, I was surprised, and felt anxious to see it with
my own eyes. Afterwards, when experience also had confirmed its truth,
I sought long among the various sects for an explanation, and, with
the exception of that which gave the first place to attraction, I
could find none which even approached plausibility, all the others
being ridiculous and obviously quite untenable. 

What happens, then, is the following. When our peasants are bringing
corn from the country into the city in wagons, and wish to filch some
away without being detected, they fill earthen jars with water and
stand them among the corn; the corn then draws the moisture into itself
through the jar and acquires additional bulk and weight, but the fact
is never detected by the onlookers unless someone who knew about the
trick before makes a more careful inspection. Yet, if you care to
set down the same vessel in the very hot sun, you will find the daily
loss to be very little indeed. Thus corn has a greater power than
extreme solar heat of drawing to itself the moisture in its neighbourhood.
Thus the theory that the water is carried towards the rarefied part
of the air surrounding us (particularly when that is distinctly warm)
is utter nonsense; for although it is much more rarefied there than
it is amongst the corn, yet it does not take up a tenth part of the
moisture which the corn does. 

15. Since, then, we have talked sufficient nonsense- not willingly,
but because we were forced, as the proverb says, "to behave madly
among madmen"- let us return again to the subject of urinary secretion.
Here let us forget the absurdities of Asclepiades, and, in company
with those who are persuaded that the urine does pass through the
kidneys, let us consider what is the character of this function. For,
most assuredly, either the urine is conveyed by its own motion to
the kidneys, considering this the better course (as do we when we
go off to market!), or, if this be impossible, then some other reason
for its conveyance must be found. What, then, is this? If we are not
going to grant the kidneys a faculty for attracting this particular
quality, as Hippocrates held, we shall discover no other reason. For,
surely everyone sees that either the kidneys must attract the urine,
or the veins must propel it- if, that is, it does not move of itself.
But if the veins did exert a propulsive action when they contract,
they would squeeze out into the kidneys not merely the urine, but
along with it the whole of the blood which they contain. And if this
is impossible, as we shall show, the remaining explanation is that
the kidneys do exert traction. 

And how is propulsion by the veins impossible? The situation of the
kidneys is against it. They do not occupy a position beneath the hollow
vein [vena cava] as does the sieve-like [ethmoid] passage in the nose
and palate in relation to the surplus matter from the brain; they
are situated on both sides of it. Besides, if the kidneys are like
sieves, and readily let the thinner serous [whey-like] portion through,
and keep out the thicker portion, then the whole of the blood contained
in the vena cava must go to them, just as the whole of the wine is
thrown into the filters. Further, the example of milk being made into
cheese will show clearly what I mean. For this, too, although it is
all thrown into the wicker strainers, does not all percolate through;
such part of it as is too fine in proportion to the width of the meshes
passes downwards, and this is called whey [serum]; the remaining thick
portion which is destined to become cheese cannot get down, since
the pores of the strainers will not admit it. Thus it is that, if
the blood-serum has similarly to percolate through the kidneys, the
whole of the blood must come to them, and not merely one part of it.

What, then, is the appearance as found on dissection? 
One division of the vena cava is carried upwards to the heart, and
the other mounts upon the spine and extends along its whole length
as far as the legs; thus one division does not even come near the
kidneys, while the other approaches them but is certainly not inserted
into them. Now, if the blood were destined to be purified by them
as if they were sieves, the whole of it would have to fall into them,
the thin part being and the thick part retained above. But, as a matter
of fact, this is not so. For the kidneys lie on either side of the
vena cava. They therefore do not act like sieves, filtering fluid
sent to them by the vena cava, and themselves contributing no force.
They obviously exert traction; for this is the only remaining alternative.

How, then, do they exert this traction? If, as Epicurus thinks, all
attraction takes place by virtue of the rebounds and entanglements
of atoms, it would be certainly better to maintain that the kidneys
have no attractive action at all; for his theory, when examined, would
be found as it stands to be much more ridiculous even than the theory
of the lodestone, mentioned a little while ago. Attraction occurs
in the way that Hippocrates laid down; this will be stated more clearly
as the discussion proceeds; for the present our task is not to demonstrate
this, but to point out that no other cause of the secretion of urine
can be given except that of attraction by the kidneys, and that this
attraction does not take place in the way imagined by people who do
not allow Nature a faculty of her own. 

For if it be granted that there is any attractive faculty at all in
those things which are governed by Nature, a person who attempted
to say anything else about the absorption of nutriment would be considered
a fool. 

16. Now, while Erasistratus for some reason replied at great length
to certain other foolish doctrines, he entirely passed over the view
held by Hippocrates, not even thinking it worth while to mention it,
as he did in his work "On Deglutition"; in that work, as may be seen,
he did go so far as at least to make mention of the word attraction,
writing somewhat as follows: 

"Now, the stomach does not appear to exercise any attraction." But
when he is dealing with anadosis he does not mention the Hippocratic
view even to the extent of a single syllable. Yet we should have been
satisfied if he had even merely written this: "Hippocrates lies in
saying 'The flesh attracts both from the stomach and from without,'
for it cannot attract either from the stomach or from without." Or
if he had thought it worth while to state that Hippocrates was wrong
in criticizing the weakness of the neck of the uterus, "seeing that
the orifice of the uterus has no power of attracting semen," or if
he [Erasistratus] had thought proper to write any other similar opinion,
then we in our turn would have defended ourselves in the following
terms: 

"My good sir, do not run us down in this rhetorical fashion without
some proof; state some definite objection to our view, in order that
either you may convince us by a brilliant refutation of the ancient
doctrine, or that, on the other hand, we may convert you from your
ignorance." Yet why do I say "rhetorical"? For we too are not to suppose
that when certain rhetoricians pour ridicule upon that which they
are quite incapable of refuting, without any attempt at argument,
their words are really thereby constituted rhetoric. For rhetoric
proceeds by persuasive reasoning; words without reasoning are buffoonery
rather than rhetoric. Therefore, the reply of Erasistratus in his
treatise "On Deglutition" was neither rhetoric nor logic. For what
is it that he says? "Now, the stomach does not appear to exercise
any traction." Let us testify against him in return, and set our argument
beside his in the same form. Now, there appears to be no peristalsis
of the gullet. "And how does this appear?" one of his adherents may
perchance ask. "For is it not indicative of peristalsis that always
when the upper parts of the gullet contract the lower parts dilate?"
Again, then, we say, "And in what way does the attraction of the stomach
not appear? For is it not indicative of attraction that always when
the lower parts of the gullet dilate the upper parts contract?" Now,
if he would but be sensible and recognize that this phenomenon is
not more indicative of the one than of the other view, but that it
applies equally to both, we should then show him without further delay
the proper way to the discovery of truth. 

We will, however, speak about the stomach again. And the dispersal
of nutriment [anadosis] need not make us have recourse to the theory
regarding the natural tendency of a vacuum to become refilled, when
once we have granted the attractive faculty of the kidneys. Now, although
Erasistratus knew that this faculty most certainly existed, he neither
mentioned it nor denied it, nor did he make any statement as to his
views on the secretion of urine. 

Why did he give notice at the very beginning of his "General Principles"
that he was going to speak about natural activities- firstly what
they are, how they take place, and in what situations- and then, in
the case of urinary secretion, declared that this took place through
the kidneys, but left out its method of occurrence? It must, then,
have been for no purpose that he told us how digestion occurs, or
spends time upon the secretion of biliary superfluities; for in these
cases also it would have been sufficient to have named the parts through
which the function takes place, and to have omitted the method. On
the contrary, in these cases he was able to tell us not merely through
what organs, but also in what way it occurs- as he also did, I think,
in the case of anadosis; for he was not satisfied with saying that
this took place through the veins, but he also considered fully the
method, which he held to be from the tendency of a vacuum to become
refilled. Concerning the secretion of urine, however, he writes that
this occurs through the kidneys, but does not add in what way it occurs.
I do not think he could say that this was from the tendency of matter
to fill a vacuum, for, if this were so, nobody would have ever died
of retention of urine, since no more can flow into a vacuum than has
run out. For, if no other factor comes into operation save only this
tendency by which a vacuum becomes refilled, no more could ever flow
in than had been evacuated. Nor, could he suggest any other plausible
cause, such, for example, as the of nutriment by the stomach which
occurs in the process of anadosis; this had been entirely disproved
in the case of blood in the vena cava; it is excluded, not merely
owing to the long distance, but also from the fact that the overlying
heart, at each diastole, robs the vena cava by violence of a considerable
quantity of blood. 

In relation to the lower part of the vena cava there would still remain,
solitary and abandoned, the specious theory concerning the filling
of a vacuum. This, however, is deprived of plausibility by the fact
that people die of retention of urine, and also, no less, by the situation
of the kidneys. For, if the whole of the blood were carried to the
kidneys, one might properly maintain that it all undergoes purification
there. But, as a matter of fact, the whole of it does not go to them,
but only so much as can be contained in the veins going to the kidneys;
this portion only, therefore, will be purified. Further, the thin
serous part of this will pass through the kidneys as if through a
sieve, while the thick sanguineous portion remaining in the veins
will obstruct the blood flowing in from behind; this will first, therefore,
have to run back to the vena cava, and so to empty the veins going
to the kidneys; these veins will no longer be able to conduct a second
quantity of unpurified blood to the kidneys- occupied as they are
by the blood which had preceded, there is no passage left. What power
have we, then, which will draw back the purified blood from the kidneys?
And what power,in the next place, will bid this blood retire to the
lower part of the vena cava, and will enjoin on another quantity coming
from above not to proceed downwards before turning off into the kidneys?

Now Erasistratus realized that all these ideas were open to many objections,
and he could only find one idea which held good in all respects- namely,
that of attraction. Since, therefore, he did not wish either to get
into difficulties or to mention the view of Hippocrates, he deemed
it better to say nothing at all as to the manner in which secretion
occurs. 

But even if he kept silence, I am not going to do so. For I know that
if one passes over the Hippocratic view and makes some other pronouncement
about the function of the kidneys, one cannot fall to make oneself
utterly ridiculous. It was for this reason that Erasistratus kept
silence and Asclepiades lied; they are like slaves who have had plenty
to say in the early part of their career, and have managed by excessive
rascality to escape many and frequent accusations, but who, later,
when caught in the act of thieving, cannot find any excuse; the more
modest one then keeps silence, as though thunderstruck, whilst the
more shameless continues to hide the missing article beneath his arm
and denies on oath that he has ever seen it. For it was in this way
also that Asclepiades, when all subtle excuses had failed him and
there was no longer any room for nonsense about "conveyance towards
the rarefied part [of the air]," and when it was impossible without
incurring the greatest derision to say that this superfluity [i.e.
the urine] is generated by the kidneys as is bile by the canals in
the liver- he, then, I say, clearly lied when he swore that the urine
does not reach the kidneys, and maintained that it passes, in the
form of vapour, straight from the region of the vena cava, to collect
in the bladder. 

Like slaves, then, caught in the act of stealing, these two are quite
bewildered, and while the one says nothing, the other indulges in
shameless lying. 

17. Now such of the younger men as have dignified themselves with
the names of these two authorities by taking the appellations "Erasistrateans"
or "Asclepiadeans" are like the Davi and Getae- the slaves introduced
by the excellent Menander into his comedies. As these slaves held
that they had done nothing fine unless they had cheated their master
three times, so also the men I am discussing have taken their time
over the construction of impudent sophisms, the one party striving
to prevent the lies of Asclepiades from ever being refuted, and the
other saying stupidly what Erasistratus had the sense to keep silence
about. 

But enough about the Asclepiadeans. The Erasistrateans, in attempting
to say how the kidneys let the urine through, will do anything or
suffer anything or try any shift in order to find some plausible explanation
which does not demand the principle of attraction. 

Now those near the times of Erasistratus maintain that the parts above
the kidneys receive pure blood, whilst the watery residue, being heavy,
tends to run downwards; that this, after percolating through the kidneys
themselves, is thus rendered serviceable, and is sent, as blood, to
all the parts below the kidneys. 

For a certain period at least this view also found favour and flourished,
and was held to be true; after a time, however, it became suspect
to the Erasistrateans themselves, and at last they abandoned it. For
apparently the following two points were assumed, neither of which
is conceded by anyone, nor is even capable of being proved. The first
is the heaviness of the serous fluid, which was said to be produced
in the vena cava, and which did not exist, apparently, at the beginning,
when this fluid was being carried up from the stomach to the liver.
Why, then, did it not at once run downwards when it was in these situations?
And if the watery fluid is so heavy, what plausibility can anyone
find in the statement that it assists in the process of anadosis?

In the second place there is this absurdity, that even if it be agreed
that all the watery fluid does fall downwards, and only when it is
in the vena cava, still it is difficult, or, rather, impossible, to
say through what means it is going to fall into the kidneys, seeing
that these are not situated below, but on either side of the vena
cava, and that the vena cava is not inserted into them, but merely
sends a branch into each of them, as it also does into all the other
parts. 

What doctrine, then, took the place of this one when it was condemned?
One which to me seems far more foolish than the first, although it
also flourished at one time. For they say, that if oil be mixed with
water and poured upon the ground, each will take a different route,
the one flowing this way and the other that, and that, therefore,
it is not surprising that the watery fluid runs into the kidneys,
while the blood falls downwards along the vena cava. Now this doctrine
also stands already condemned. For why, of the countless veins which
spring from the vena cava, should blood flow into all the others,
and the serous fluid be diverted to those going to the kidneys? They
have not answered the question which was asked; they merely state
what happens and imagine they have thereby assigned the reason.

Once again, then (the third cup to the Saviour!), let us now speak
of the worst doctrine of all, lately invented by Lycus of Macedonia,
but which is popular owing to its novelty. This Lycus, then, maintains,
as though uttering an oracle from the inner sanctuary, that urine
is residual matter from the nutrition of the kidneys! Now, the amount
of urine passed every day shows clearly that it is the whole of the
fluid drunk which becomes urine, except for that which comes away
with the dejections or passes off as sweat or insensible perspiration.
This is most easily recognized in winter in those who are doing no
work but are carousing, especially if the wine be thin and diffusible;
these people rapidly pass almost the same quantity as they drink.
And that even Erasistratus was aware of this is known to those who
have read the first book of his "General Principles." Thus Lycus is
speaking neither good Erasistratism, nor good Asclepiadism, far less
good Hippocratism. He is, therefore, as the saying is, like a white
crow, which cannot mix with the genuine crows owing to its colour,
nor with the pigeons owing to its size. For all this, however, he
is not to be disregarded; he may, perhaps, be stating some wonderful
truth, unknown to any of his predecessors. 

Now it is agreed that all parts which are undergoing nutrition produce
a certain amount of residue, but it is neither agreed nor is it likely,
that the kidneys alone, small bodies as they are, could hold four
whole congii, and sometimes even more, of residual matter. For this
surplus must necessarily be greater in quantity in each of the larger
viscera; thus, for example, that of the lung, if it corresponds in
amount to the size of the viscus, will obviously be many times more
than that in the kidneys, and thus the whole of the thorax will become
filled, and the animal will be at once suffocated. But if it be said
that the residual matter is equal in amount in each of the other parts,
where are the bladders, one may ask, through which it is excreted?
For, if the kidneys produce in drinkers three and sometimes four congii
of superfluous matter, that of each of the other viscera will be much
more, and thus an enormous barrel will be needed to contain the waste
products of them all. Yet one often urinates practically the same
quantity as one has drunk, which would show that the whole of what
one drinks goes to the kidneys. 

Thus the author of this third piece of trickery would appear to have
achieved nothing, but to have been at once detected, and there still
remains the original difficulty which was insoluble by Erasistratus
and by all others except Hippocrates. I dwell purposely on this topic,
knowing well that nobody else has anything to say about the function
of the kidneys, but that either we must prove more foolish than the
very butchers if we do not agree that the urine passes through the
kidneys; or, if one acknowledges this, that then one cannot possibly
give any other reason for the secretion than the principle of attraction.

Now, if the movement of urine does not depend on the tendency of a
vacuum to become refilled, it is clear that neither does that of the
blood nor that of the bile; or if that of these latter does so, then
so also does that of the former. For they must all be accomplished
in one and the same way, even according to Erasistratus himself.

This matter, however, will be discussed more fully in the book following
this. 

----------------------------------------------------------------------

BOOK TWO

1. In the previous book we demonstrated that not only Erasistratus,
but also all others who would say anything to the purpose about urinary
secretion, must acknowledge that the kidneys possess some faculty
which attracts to them this particular quality existing in the urine.
Besides this we drew attention to the fact that the urine is not carried
through the kidneys into the bladder by one method, the blood into
parts of the animal by another, and the yellow bile separated out
on yet another principle. For when once there has been demonstrated
in any one organ, the drawing, or so-called epispastic faculty, there
is then no difficulty in transferring it to the rest. Certainly Nature
did not give a power such as this to the kidneys without giving it
also to the vessels which abstract the biliary fluid, nor did she
give it to the latter without also it to each of the other parts.
And, assuredly, if this is true, we must marvel that Erasistratus
should make statements concerning the delivery of nutriment from the
food-canal which are so false as to be detected even by Asclepiades.
Now, Erasistratus considers it absolutely certain that, if anything
flows from the veins, one of two things must happen: either a completely
empty space will result, or the contiguous quantum of fluid will run
in and take the place of that which has been evacuated. Asclepiades,
however, holds that not one of two, but one of three things must be
said to result in the emptied vessels: either there will be an entirely
empty space, or the contiguous portion will flow in, or the vessel
will contract. For whereas, in the case of reeds and tubes it is true
to say that, if these be submerged in water, and are emptied of the
air which they contain in their lumens, then either a completely empty
space will be left, or the contiguous portion will move onwards; in
the case of veins this no longer holds, since their coats can collapse
and so fall in upon the interior cavity. It may be seen, then, how
false this hypothesis- by Zeus, I cannot call it a demonstration!-
of Erasistratus is. 

And, from another point of view, even if it were true, it is superfluous,
if the stomach has the power of compressing the veins, as he himself
supposed, and the veins again of contracting upon their contents and
propelling them forwards. For, apart from other considerations, no
plethora would ever take place in the body, if delivery of nutriment
resulted merely from the tendency of a vacuum to become refilled.
Now, if the compression of the stomach becomes weaker the further
it goes, and cannot reach to an indefinite distance, and if, therefore,
there is need of some other mechanism to explain why the blood is
conveyed in all directions, then the principle of the refilling of
a vacuum may be looked on as a necessary addition; there will not,
however, be a plethora in any of the parts coming after the liver,
or, if there be, it will be in the region of the heart and lungs;
for the heart alone of the parts which come after the liver draws
the nutriment into its right ventricle, thereafter sending it through
the arterioid vein to the lungs (for Erasistratus himself will have
it that, owing to the membranous excrescences, no other parts save
the lungs receive nourishment from the heart). If, however, in order
to explain how plethora comes about, we suppose the force of compression
by the stomach to persist indefinitely, we have no further need of
the principle of the refilling of a vacuum, especially if we assume
contraction of the veins in addition- as is, again, agreeable to Erasistratus
himself. 

2. Let me draw his attention, then, once again, even if he does not
wish it, to the kidneys, and let me state that these confute in the
very clearest manner such people as object to the principle of attraction.
Nobody has ever said anything plausible, nor, as we previously showed,
has anyone been able to discover, by any means, any other cause for
the secretion of urine; we necessarily appear mad if we maintain that
the urine passes into the kidneys in the form of vapour, and we certainly
cut a poor figure when we talk about the tendency of a vacuum to become
refilled; this idea is foolish in the case of blood, and impossible,
nay, perfectly nonsensical, in the case of the urine. 

This, then, is one blunder made by those who dissociate themselves
from the principle of attraction. Another is that which they make
about the secretion of yellow bile. For in this case, too, it is not
a fact that when the blood runs past the mouths [stomata] of the bile-ducts
there will be a thorough separation out [secretion] of biliary waste-matter.
"Well," say they, "let us suppose that it is not secreted but carried
with the blood all over the body." But, you sapient folk, Erasistratus
himself supposed that Nature took thought for the animals' future,
and was workmanlike in her method; and at the same time he maintained
that the biliary fluid was useless in every way for the animals. Now
these two things are incompatible. For how could Nature be still looked
on as exercising forethought for the animal when she allowed a noxious
humour such as this to be carried off and distributed with the blood?...

This, however, is a small matter. I shall again point out here the
greatest and most obvious error. For if the yellow bile adjusts itself
to the narrower vessels and stomata, and the blood to the wider ones,
for no other reason than that blood is thicker and bile thinner, and
that the stomata of the veins are wider and those of the bile-ducts
narrower, then it is clear that this watery and serous superfluity,
too, will run out into the bile-ducts quicker than does the bile,
exactly in proportion as it is thinner than the bile! How is it, then,
that it does not run out? "Because," it may be said, "urine is thicker
than bile!" This was what one of our Erasistrateans ventured to say,
herein clearly disregarding the evidence of his senses, although he
had trusted these in the case of the bile and blood. For, if it be
that we are to look on bile as thinner than blood because it runs
more, then, since the serous residue passes through fine linen or
lint or a or a sieve more easily even than does bile, by these tokens
bile must also be thicker than the watery fluid. For here, again,
there is no argument which will demonstrate that bile is thinner than
the serous superfluities. 

But when a man shamelessly goes on using circumlocutions, and never
acknowledges when he has had a fall, he is like the amateur wrestlers,
who, when they have been overthrown by the experts and are lying on
their backs on the ground, so far from recognizing their fall, actually
seize their victorious adversaries by the necks and prevent them from
getting away, thus supposing themselves to be the winners!

3. Thus, every hypothesis of channels as an explanation of natural
functioning is perfect nonsense. For, if there were not an inborn
faculty given by Nature to each one of the organs at the very beginning,
then animals could not continue to live even for a few days, far less
for the number of years which they actually do. For let us suppose
they were under no guardianship, lacking in creative ingenuity and
forethought; let us suppose they were steered only by material forces,
and not by any special faculties (the one attracting what is proper
to it, another rejecting what is foreign, and yet another causing
alteration and adhesion of the matter destined to nourish it); if
we suppose this, I am sure it would be ridiculous for us to discuss
natural, or, still more, psychical, activities- or, in fact, life
as a whole. 

For there is not a single animal which could live or endure for the
shortest time if, possessing within itself so many different parts,
it did not employ faculties which were attractive of what is appropriate,
eliminative of what is foreign, and alterative of what is destined
for nutrition. On the other hand, if we have these faculties, we no
longer need channels, little or big, resting on an unproven hypothesis,
for explaining the secretion of urine and bile, and the conception
of some favourable situation (in which point alone Erasistratus shows
some common sense, since he does regard all the parts of the body
as having been well and truly placed and shaped by Nature).

But let us suppose he remained true to his own statement that Nature
is "artistic"- this Nature which, at the beginning, well and truly
shaped and disposed all the parts of the animal, and, after carrying
out this function (for she left nothing undone), brought it forward
to the light of day, endowed with certain faculties necessary for
its very existence, and, thereafter, gradually increased it until
it reached its due size. If he argued consistently on this principle,
I fail to see how he can continue to refer natural functions to the
smallness or largeness of canals, or to any other similarly absurd
hypothesis. For this Nature which shapes and gradually adds to the
parts is most certainly extended throughout their whole substance.
Yes indeed, she shapes and nourishes and increases them through and
through, not on the outside only. For Praxiteles and Phidias and all
the other statuaries used merely to decorate their material on the
outside, in so far as they were able to touch it; but its inner parts
they left unembellished, unwrought, unaffected by art or forethought,
since they were unable to penetrate therein and to reach and handle
all portions of the material. It is not so, however, with Nature.
Every part of a bone she makes bone, every part of the flesh she makes
flesh, and so with fat and all the rest; there is no part which she
has not touched, elaborated, and embellished. Phidias, on the other
hand, could not turn wax into ivory and gold, nor yet gold into wax:
for each of these remains as it was at the commencement, and becomes
a perfect statue simply by being clothed externally in a form and
artificial shape. But Nature does not preserve the original character
of any kind of matter; if she did so, then all parts of the animal
would be blood- that blood, namely, which flows to the semen from
the impregnated female and which is, so to speak, like the statuary's
wax, a single uniform matter, subjected to the artificer. From this
blood there arises no part of the animal which is as red and moist
[as blood is], for bone, artery, vein, nerve, cartilage, fat, gland,
membrane, and marrow are not blood, though they arise from it.

I would then ask Erasistratus himself to inform me what the altering,
coagulating, and shaping agent is. He would doubtless say, "Either
Nature or the semen," meaning the same thing in both cases, but explaining
it by different devices. For that which was previously semen, when
it begins to procreate and to shape the animal, becomes, so to say,
a special nature. For in the same way that Phidias possessed the faculties
of his art even before touching his material, and then activated these
in connection with this material (for every faculty remains inoperative
in the absence of its proper material), so it is with the semen: its
faculties it possessed from the beginning, while its activities it
does not receive from its material, but it manifests them in connection
therewith. 

And, of course, if it were to be overwhelmed with a great quantity
of blood, it would perish, while if it were to be entirely deprived
of blood it would remain inoperative and would not turn into a nature.
Therefore, in order that it may not perish, but may become a nature
in place of semen, there must be an afflux to it of a little blood-
or, rather, one should not say a little, but a quantity commensurate
with that of the semen. What is it then that measures the quantity
of this afflux? What prevents more from coming? What ensures against
a deficiency? What is this third overseer of animal generation that
we are to look for, which will furnish the semen with a due amount
of blood? What would Erasistratus have said if he had been alive,
and had been asked this question? Obviously, the semen itself. This,
in fact, is the artificer analogous with Phidias, whilst the blood
corresponds to the statuary's wax. 

Now, it is not for the wax to discover for itself how much of it is
required; that is the business of Phidias. Accordingly the artificer
will draw to itself as much blood as it needs. Here, however, we must
pay attention and take care not unwittingly to credit the semen with
reason and intelligence; if we were to do this, we would be making
neither semen nor a nature, but an actual living animal. And if we
retain these two principles- that of proportionate attraction and
that of the non-participation of intelligence- we shall ascribe to
the semen a faculty for attracting blood similar to that possessed
by the lodestone for iron. Here, then, again, in the case of the semen,
as in so many previous instances, we have been compelled to acknowledge
some kind of attractive faculty. 

And what is the semen? Clearly the active principle of the animal,
the material principle being the menstrual blood. Next, seeing that
the active principle employs this faculty primarily, therefore, in
order that any one of the things fashioned by it may come into existence,
it [the principle] must necessarily be possessed of its own faculty.
How, then, was Erasistratus unaware of it, if the primary function
of the semen be to draw to itself a due proportion of blood? Now,
this fluid would be in due proportion if it were so thin and vaporous,
that, as soon as it was drawn like dew into every part of the semen,
it would everywhere cease to display its own particular character;
for so the semen will easily dominate and quickly assimilate it- in
fact, will use it as food. It will then, I imagine, draw to itself
a second and a third quantum, and thus by feeding it acquires for
itself considerable bulk and quantity. In fact, the alterative faculty
has now been discovered as well, although about this also has not
written a word. And, thirdly the shaping faculty will become evident,
by virtue of which the semen firstly surrounds itself with a thin
membrane like a kind of superficial condensation; this is what was
described by Hippocrates in the sixth-day birth, which, according
to his statement, fell from the singing-girl and resembled the pellicle
of an egg. And following this all the other stages will occur, such
as are described by him in his work "On the Child's Nature."

But if each of the parts formed were to remain as small as when it
first came into existence, of what use would that be? They have, then,
to grow. Now, how will they grow? By becoming extended in all directions
and at the same time receiving nourishment. And if you will recall
what I previously said about the bladder which the children blew up
and rubbed, you will also understand my meaning better as expressed
in what I am now about to say. 

Imagine the heart to be, at the beginning, so small as to differ in
no respect from a millet-seed, or, if you will, a bean; and consider
how otherwise it is to become large than by being extended in all
directions and acquiring nourishment throughout its whole substance,
in the way that, as I showed a short while ago, the semen is nourished.
But even this was unknown to Erasistratus- the man who sings the artistic
skill of Nature! He imagines that animals grow like webs, ropes, sacks,
or baskets, each of which has, woven on to its end or margin, other
material similar to that of which it was originally composed.

But this, most sapient sir, is not growth, but genesis! For a bag,
sack, garment, house, ship, or the like is said to be still coming
into existence [undergoing genesis] so long as the appropriate form
for the sake of which it is being constructed by the artificer is
still incomplete. Then, when does it grow? Only when the basket, being
complete, with a bottom, a mouth, and a belly, as it were, as well
as the intermediate parts, now becomes larger in all these respects.
"And how can this happen?" someone will ask. Only by our basket suddenly
becoming an animal or a plant; for growth belongs to living things
alone. Possibly you imagine that a house grows when it is being built,
or a basket when being plated, or a garment when being woven? It is
not so, however. Growth belongs to that which has already been completed
in respect to its form, whereas the process by which that which is
still becoming attains its form is termed not growth but genesis.
That which is, grows, while that which is not, becomes. 

4. This also was unknown to Erasistratus, whom nothing escaped, if
his followers speak in any way truly in maintaining that he was familiar
with the Peripatetic philosophers. Now, in so far as he acclaims Nature
as being an artist in construction, even I recognize the Peripatetic
teachings, but in other respects he does not come near them. For if
anyone will make himself acquainted with the writings of Aristotle
and Theophrastus, these will appear to him to consist of commentaries
on the Nature-lore [physiology] of Hippocrates- according to which
the principles of heat, cold, dryness and moisture act upon and are
acted upon by one another, the hot principle being the most active,
and the cold coming next to it in power; all this was stated in the
first place by Hippocrates and secondly by Aristotle. Further, it
is at once the Hippocratic and the Aristotelian teaching that the
parts which receive that nourishment throughout their whole substance,
and that, similarly, processes of mingling and alteration involve
the entire substance. Moreover, that digestion is a species of alteration-
a transmutation of the nutriment into the proper quality of the thing
receiving it; that blood-production also is an alteration, and nutrition
as well; that growth results from extension in all directions, combined
with nutrition; that alteration is effected mainly by the warm principle,
and that therefore digestion, nutrition, and the generation of the
various humours, as well as the qualities of the surplus substances,
result from the innate heat; all these and many other points besides
in regard to the aforesaid faculties, the origin of diseases, and
the discovery of remedies, were correctly stated first by Hippocrates
of all writers whom we know, and were in the second place correctly
expounded by Aristotle. Now, if all these views meet with the approval
of the Peripatetics, as they undoubtedly do, and if none of them satisfy
Erasistratus, what can the Erasistrateans possibly mean by claiming
that their leader was associated with these philosophers? The fact
is, they revere him as a god, and think that everything he says is
true. If this be so, then we must suppose the Peripatetics to have
strayed very far from truth, since they approve of none of the ideas
of Erasistratus. And, indeed, the disciples of the latter produce
his connection wit