by Aristotle
[35] To suppose, then, either that heat and cold are the causes of male and female, or that the different sexes come from the right and left, is not altogether [765b1] unreasonable in itself; for the right of the body is hotter than the left, and the concocted semen is hotter than the unconcocted; again, the thickened is concocted, and the more thickened is more fertile. Yet to put it in this way is to seek for the [5] cause from too remote a starting-point; we must draw near the primary causes in so far as it is possible for us.
We have, then, previously spoken elsewhere of both the body as a whole and its parts, explaining what each part is and for what reason it exists. But the male and female are distinguished by a certain capacity and incapacity. (For the male is that [10] which can concoct and form and discharge a semen carrying with it the principle of form—by ‘principle’ I do not mean a material principle out of which comes into being an offspring resembling the parent, but I mean the first moving cause, whether it have power to act as such in the thing itself or in something else—but the [15] female is that which receives semen, but cannot form it or discharge it.) And all concoction works by means of heat. Therefore the males of animals must needs be hotter than the females. For it is by reason of cold and incapacity that the female is more abundant in blood in certain parts of her anatomy, and this abundance is an evidence of the exact opposite of what some suppose, thinking that the female is hotter than the male for this reason, i.e. the discharge of menstrual fluids. It is true [20] that blood is hot, and that which has more of it is hotter. But they assume that this discharge occurs through excess of blood and of heat, as if it were possible for everything to be equally blood if only it be liquid and sanguineous in colour, and as if it might not become less in quantity but purer in quality in those who assimilate [25] nourishment properly. In fact they look upon this residual discharge in the same light as that of the intestines, when they think that a greater amount of it is a sign of a hotter nature, whereas the truth is just the opposite. For consider the production of fruit; the nutriment in its first stage is abundant, but the useful product derived from it is small, indeed the final result is nothing at all compared to the quantity in [30] the first stage. So is it with the body; the various parts receive and work up the nutriment, from the whole of which the final result is quite small. This is blood in some animals, in some its analogue. Now since the one sex is able and the other is [35] unable to reduce the residual secretion to a pure form, and every capacity has a certain corresponding organ, whether the faculty produces the desired results in a lower degree or in a higher degree, and since the two sexes correspond in this [766a1] manner (the terms ‘able’ and ‘unable’ being used in more senses than one)— therefore it is necessary that both female and male should have organs. Accordingly the one has the uterus, the other the male organs.
Again, nature gives both the faculty and the organ to each individual at the [5] same time, for it is better so. Hence each region comes into being along with the secretions and the faculties, as e.g. the faculty of sight is not perfected without the eye, nor the eye without the faculty of sight; and so too the intestine and bladder come into being along with the faculty of forming the residues. And since that from which an organ comes into being and that by which it is increased are the same (i.e. [10] the nutriment), each of the parts will be made out of such a material and such residual matter as it is able to receive. In the second place, again, it is formed, as we say, in a certain sense, out of its opposite. Thirdly, we must understand besides this that, if it is true that when a thing perishes it becomes the opposite of what it was, it is necessary also that what is not under the sway of that which made it must change [15] into its opposite. After these premisses it will perhaps be now clearer for what reason one embryo becomes female and another male. For when the first principle does not bear sway and cannot concoct the nourishment through lack of heat nor bring it into its proper form, but is defeated in this respect, then must the material [20] change into its opposite. Now the female is opposite to the male, and that in so far as the one is female and the other male. And since it differs in its faculty, its organ also is different, so that the embryo changes into this state. And as one part of first-rate importance changes, the whole system of the animal differs greatly in form along with it. This may be seen in the case of eunuchs, who, though mutilated in one part [25] alone, depart so much from their original appearance and approximate closely to the female form. The reason of this is that some of the parts are principles, and when a principle is moved many of the parts that go along with it must change with it.
[30] If then the male is a principle and a cause, and the male is such in virtue of a certain capacity and the female is such in virtue of an incapacity, and if the definition of the capacity and of the incapacity is ability or inability to concoct the nourishment in its ultimate stage, this being called blood in the sanguinea and the analogue of blood in the other animals, and if the cause of this capacity is in the first principle and in the part which contains the principle of natural heat—therefore a [766b1] heart must be formed in the sanguinea (and the resulting animal will be either male or female), and in the other kinds which possess the sexes must be formed that which is analogous to the heart.
This, then, is the first principle and cause of male and female, and this is the part of the body in which it resides. But the animal becomes definitely female or [5] male by the time when it possesses also the parts by which the female differs from the male, for it is not in virtue of any part you please that it is male or female, any more than it is able to see or hear by possessing any part you please.
To recapitulate, we say that the semen has been laid down to be the ultimate residue of the nutriment. By ultimate I mean that which is carried to every part of [10] the body, and this is also the reason why the offspring is like the parent. For it makes no difference whether we say that the semen comes from all the parts or goes to all of them, but the latter is the better. But the semen of the male differs in that it contains a principle within itself of such a kind as to set up movements also in the embryo and to concoct thoroughly the ultimate nourishment, whereas the secretion [15] of the female contains material alone. If, then, the male element prevails it draws the female element into itself, but if it is prevailed over it changes into the opposite or is destroyed. But the female is opposite to the male, and is female because of its inability to concoct and of the coldness of the sanguineous nutriment. And nature assigns to each of the residues the part fitted to receive it. But the semen is a residue, [20] and this in the hotter animals with blood, i.e. the males, is moderate in quantity, which is why the recipient parts of this residue in males are only passages. But the females, owing to inability to concoct, have a great quantity of blood, for it cannot be worked up into semen. Therefore they must also have a part to receive this, and this part must be unlike the passages of the male and of a considerable size. This is [25] why the uterus is of such a nature, this being the part by which the female differs from the male.
2 · We have thus stated for what reason the one becomes female and the other male. Observed facts confirm what we have said. For more females are produced by the young and by those verging on old age than by those in the prime of [30] life; in the former the heat is not yet perfect, in the latter it is failing. And those of a moister and more feminine state of body are more wont to beget females, and a liquid semen causes this more than a thicker; now all these characteristics come of deficiency in natural heat.
Again, more males are born if copulation takes place when north than when south winds are blowing; for animals’ bodies are more liquid when the wind is in the [35] south, so that they produce more residue—and more residue is harder to concoct; hence the semen of the males is more liquid, and so is the discharge of the menstrual fluids in women.
Also the fact that menstruation occurs in the course of nature rather when the [767a1] month is waning is due to the same causes. For this time of the month is colder and mois
ter because of the waning and failure of the moon; as the sun makes winter and summer in the year as a whole, so does the moon in the month. This is not due to the [5] turning of the moon, but it grows warmer as the light increases and colder as it wanes.
The shepherds also say that it not only makes a difference in the production of males and females if copulation takes place during northern or southerly winds, but [10] even if the animals while copulating look towards the south or north; so small a thing will sometimes turn the scale and cause cold or heat, and these again influence generation.
The male and female, then, are distinguished generally, as compared with one another in connexion with the production of male and female offspring, for the causes stated. However, they also need a certain correspondence with one another; [15] for all things that come into being as products of art or of nature exist in virtue of a certain ratio. Now if the hot preponderates too much it dries up the liquid; if it is very deficient it does not solidify it; for the product we need the due mean between the extremes. Otherwise it will be as in cooking; too much fire burns the meat, too [20] little does not cook it, and in either case the process is a failure. So also there is need of due proportion in the mixture of the male and female elements. And for this cause it often happens to many of both sexes that they do not generate with one another, but if divorced and remarried to others do generate; and these oppositions [25] show themselves sometimes in youth, sometimes in advanced age, alike as concerns fertility or infertility, and as concerns generation of male or female offspring.
One country also differs from another in these respects, and one water from another, for the same reasons. For the nourishment and the condition of the body [30] are of such or such a kind because of the tempering of the surrounding air and of the food entering the body, especially the water; for men consume more of this than of anything else, and this enters as nourishment into all food, even solids. Hence hard waters cause infertility, and cold waters the birth of females. [35]
3 · The same causes must be held responsible for the facts that some children resemble their parents, while others do not (some being like the father and others like the mother, both in the body as a whole and in each part); and that they [767b1] resemble their parents more than remoter ancestors, and resemble those ancestors more than any chance individual; and that males rather resemble their fathers, females their mothers; and that some, though resembling none of their relations, yet do at any rate resemble a human being, but others are not even like a human being [5] but a monstrosity. For even he who does not resemble his parents is already in a certain sense a monstrosity; for in these cases nature has in a way departed from the type. The first departure indeed is that the offspring should become female instead of male; this, however, is a natural necessity. (For the class of animals divided into [10] sexes must be preserved, and as it is possible for the male sometimes not to prevail over the female, either through youth or age or some other such cause, it is necessary that animals should produce female young.) And the monstrosity, though not necessary in regard of a final cause and an end, yet is necessary accidentally. As [15] for the origin of it, we must look at it in this way. If the generative residue in the menstrual fluids is properly concocted, the movement imparted by the male will make the form of the embryo in the likeness of itself. (Whether we say that it is the semen or this movement that makes each of the parts grow, makes no difference; nor again whether we say that it makes them grow or forms them from the [20] beginning, for the formula of the movement is the same in either case.) Thus if this movement prevail, it will make the embryo male and not female, like the father and not like the mother; if it prevail not, the embryo is deficient in that faculty in which it has not prevailed. By ‘each faculty’ I mean this. That which generates is not only [25] male but also a certain sort of male, e.g. Coriscus or Socrates, and it is not only Coriscus but also a man. In this way some of the characteristics of the father are more near to him, others more remote from him considered simply as a parent and not in reference to his accidental qualities (as for instance if the parent is a scholar or the neighbour of some particular person). Now the peculiar and individual has [30] always more force in generation. Coriscus is both a man and an animal, but his manhood is nearer to what is peculiar to him than is his animal-hood. In generation both the individual and the class are operative, but the individual is the more so of [35] the two, for this is the substance. And the offspring is produced indeed of a certain quality, but also as a certain ‘this’, and this latter is the substance. Therefore it is from the forces of all such things that the movements come which exist in the semen; potentially from remoter ancestors but in a higher degree from whatever [768a1] individual is nearer (and by the individual I mean e.g. Coriscus or Socrates). Now since everything changes not into anything haphazard but into its opposite, therefore also that which is not prevailed over in generation must change and become the opposite, in respect of that particular force in which the generative and [5] moving element has not prevailed. If then it has not prevailed in so far as it is male, the offspring becomes female; if in so far as it is Coriscus or Socrates, the offspring does not resemble the father but the mother. For as father and mother are opposed in general, so also the individual father is opposed to the individual mother. The like applies also to the forces that come next in order, for the offspring always changes [10] rather into the likeness of the nearer ancestor, both in the paternal and in the maternal line.
Some of the movements exist actually, others potentially; actually, those of the father and the general type, as man and animal; potentially, those of the female and [15] the remoter ancestors. Now if it lose its own nature, it changes to its opposites, but the movements which form the embryo relapse into those nearly connected with them; for instance, if the movement of the male parent relapses, it changes by a very slight difference into that of his father, and in the next instance into that of his grandfather; and in this way in the female line too the movement of the female [20] parent changes into that of her mother, and, if not into this, then into that of her grandmother; and similarly also with the more remote ancestors.
Naturally then it is most likely that the characteristics of male and of the father will go together, whether they prevail or are prevailed over. For the difference between them is small so that there is no difficulty in both concurring, for Socrates is an individual man with certain characteristics. Hence for the most part the male offspring resemble the father, and the female the mother. For the loss of [25] both characters takes place at once, and the change is into the two opposites; now female is opposed to male, and mother to father.
But if the movement coming from the male principle prevails while that coming from Socrates does not, or vice versa, then the result is that male children [30] are produced resembling the mother and female children resembling the father.
If again the movements relapse, then if the male character remains but the movement coming from the individual Socrates relapses into that of the father of Socrates, the result will be a male child resembling its grandfather or some other of its more remote ancestors in the male line on the same principle. If the male principle be prevailed over, the child will be female and resembling most probably its mother, but, if the movement coming from the mother also relapses, it will [35] resemble its mother’s mother or the resemblance will be to some other of its more remote ancestors in the female line on the same principle.
The same applies also to the separate parts, for often some of these take after [768b1] the father, and others after the mother, and yet others after some of the remoter ancestors. For, as has been often said already, some of the movements which form the parts exist actually and others potentially. We must grasp certain general principles, not only that just mentioned (that some of the movements exist [5] potentially and others actually), but also two others, that if a character be prevailed over it changes into its opposite, and, if it relapse it is resolved into the movement next allied t
o it—if less, into that which is near, if more, into that which is further removed. Finally, the movements are so confused together that there is no [10] resemblance to any of the family or kindred, but the only character that remains is that common to all, i.e. being a man. The reason for this is that this accompanies all the individual characteristics; man is universal, while Socrates, the father, and the mother, whoever she may be, are individuals.
The reason why the movements relapse is this. The agent is itself acted upon by [15] that on which it acts; thus that which cuts is blunted by that which is cut by it, that which heats is cooled by that which is heated by it, and in general the moving cause (except in the case of the first cause of all) does itself receive some motion in return; e.g. what pushes is itself in a way pushed again and what crushes is itself crushed [20] again. Sometimes it is altogether more acted upon than acting, so that what is heating or cooling something else is itself cooled or heated, sometimes having produced no effect, sometimes less than it has itself received. (This question has been treated in the special discussion of action and reaction, where it is laid down in what classes of things action and reaction exist.) Now that which is acted on escapes [25] and is not mastered, either through deficiency of power in the concocting and moving agent or because what should be concocted and formed into distinct parts is too cold and in too great quantity. Thus the moving agent, mastering it in one part but not in another, makes the embryo in formation to be multiform, as happens with [30] athletes because they eat so much. For owing to the quantity of their food their nature is not able to master it in such a way that their form grows proportionately and remains symmetrical; therefore their limbs develop irregularly, sometimes indeed almost so much that no one of them resembles what it was before. Similar to this is also the disease known as satyriasis, in which the face appears like that of [35] some other creature—a satyr—owing to a quantity of unconcocted humour being diverted into parts of the face.