In which season coition flourishes more.
One asks further in which season coition flourishes more.
1. And it seems that it flourishes more in summer. For the Philosopher says in the second book of On Generation that "the sun's approach to us is the cause of generation, and its retreat is the cause of corruption." But during summer the sun is nearer to us. Therefore, the generative power particularly flourishes then.
2. Moreover, it seems that it flourishes more in spring. For it is then that each one is perfected, when it can reproduce one like itself, according to the Philosopher in the second book of On the Soul. Thus, when the powers are more perfect, they are then more generative. But the powers in animated beings are more perfected in spring, for it is then that nature especially expels superfluities, for this is when rashes and scabs especially appear, and these attest to the power of nature as an expelling force. Therefore, the generative power especially flourishes in spring.
That it flourishes in winter can be proved through the arguments adduced to the previous question.
To this, one must reply that the generative power is twofold. One is superior, and this consists in the sun and the moon and the other planets, and the other is inferior, and this is different in different beings. The first generative power especially flourishes in spring, then in summer, third in autumn, but least of all in winter. But it exists in some animals in various ways, because in some the inferior power agrees with the superior, and in these the generative power especially flourishes in spring, for example, in plants and in some middling animals. But in others, such as flies and serpents, the inferior power does not agree with the superior, owing to the weakness of the heat, and in such as these it flourishes more in summer than in spring. And the same thing occurs in large animals that live on things born of the earth, since in winter, owing to the lack of nutriment, they become very thin, and they are not stimulated to generate until they have become a good bit fatter, which does not occur in them before summer or autumn. In ones like this the generative power especially flourishes in summer or autumn.
1. On to the arguments. It is apparent from this that the first argument proves that in summer the generative power does not flourish as much in animals that are not hot in themselves.
Or, it can be better said in another way that neither an excess of heat nor an excess of cold is required for the generative power, because if the heat were excessive it would consume the moisture, which is the semen's matter, and if it were cold the pores would close through which the semen has to exit. And this is why a temperate heat is required, which is particularly present in spring, because spring has a warm and moist complexion naturally, just as the semen does.
2. To the second argument one must reply that it particularly flourishes in spring except in those animals that are too cold. Ones like this wait for the summer before they have intercourse.
Whether the male and the female are especially urged on at the same time to generate.
One asks further whether humans, male and female, have the same time for generation or are especially urged on or moved to generate at the same time.
1. It seems so. For a human naturally has a warm and moist complexion. Therefore, the powers in a human are determined for the same time. But each one does better in the season dissimilar [in complexion] to him and does worse in the season that is like him. For the author of the Six Principles says that humans, who have a dry and arid complexion, do worse in autumn and better in spring. Therefore, the human, male as well as female, is especially aroused to intercourse in autumn, during a dissimilar season.
2. The same thing is clear in other animals as well and similarly in plants of the same species.
The Philosopher says the opposite. For he says that "a man has intercourse especially in the winter, and woman in summer."
To this one must reply that a human, unlike other animals, does not have a season determined for coition. And the reason for this is that a human lives according to reason, which is capable of opposites. Now, "the genus of humans lives both by reason and by art," as he said in the first book of the Metaphysics. But other animals are ruled by the instinct of nature, which always acts in the same way unless it is impeded.
Another cause is that the human has a nutriment that is appropriate and adequate for him in every season, and the same is true for his other necessaries. But this does not occur in other animals. And this is why there can be material for semen and the power for intercourse in the human in every season. Nevertheless, intercourse flourishes in the male more in winter with respect to his own makeup than in the other seasons, and in a female this occurs in summer. And the reason for this is that generally a man has a hotter complexion than a woman, and this is why in summer, on account of the surrounding heat, the interior heat is dulled, because the exterior, surrounding heat causes the natural interior heat to disperse and to escape. But in winter the heat is put to flight by the surrounding cold and is gathered together on the inside, and the united power is stronger than one dispersed on its own. But the opposite is the case in a woman, because in winter, on account of the surrounding cold, the pores and pathways of the semen are constricted and blocked, and in summer they are opened by the accidental heat, and this is why a man is especially potent for intercourse in winter, whereas a woman is so in summer, and this is clear.
1. On to the arguments. To the first, one must reply that a man and a woman can have intercourse in the same season, but nevertheless a man of his own accord has intercourse more in winter than in other seasons, and a woman has intercourse more in summer.
2. To the second argument one must reply that animals and plants live and are ruled by nature, which acts in a uniform manner, but the human is ruled by reason.
Related questions about intercourse.
Related to this, one can ask why the woman can conceive at twelve years of age, whereas the man does not usually generate before the fourteenth year, and why at the other end the woman ceases to conceive before a man [homo] ceases to generate.
Again, one may inquire why things more quickly deteriorate which are made by those having intercourse secretly, frequently, or with pleasure. For a cheese made by a woman who secretly has intercourse quickly putrefies, and a sword made by [such] a man rusts more quickly.
Again, one may ask why dogs follow such people so often.
Again, one may ask why men are more ashamed of this sort of act than of another.
To the first, one must reply that a woman conceives more quickly for two reasons: one is owing to the matter, like the abundance of menstrual blood, and the other is owing to the efficient cause. For a woman is colder and moister, and, owing to the weakness of her heat, she therefore more quickly overflows with menses or abounds with semen, which is a superfluity of the aliment. But in a man the heat is more potent and digests the aliment better by converting it into the substance of the members, so much so that little of the superfluity is left over, and as a result there is little semen, and this is why a woman is more quickly apt to conceive than a man is apt to generate.
Another cause is that more is required for acting than for undergoing. And this is why it is required that the power of the man be more fortified, since it is active, than the power of the woman, since it is passive, and this is why he needs more time [to generate]. But the less dense something is, the more quickly it is penetrated even by something corrupting, and a woman has a less dense complexion, and this is why her power is more quickly consumed by an exterior corruptive agent, and this is why she ceases to conceive more quickly than a man ceases to generate.
To the second argument one must say that just as the eye of a menstruating woman infects a mirror (because the humors then abundant in the eye infect the air near the eye, and this infects the next bit of air, and so on up to the mirror), so too in people who have intercourse a great deal it is as if all their parts were infected, and therefore things that are touched by them receive an infection and as a result tend more quickly toward corruption.
To the third, one must reply that dogs take more pleasure in a strong odor and follow after dead bodies. Further, the body of a person who has a great deal of intercourse closely approaches in its disposition the nature of a dead body owing to an abundance of corrupt semen. This is why dogs, which have a very good sense of smell, follow them.
To the fourth, one must reply that a human is naturally ashamed by evildoing. Thus a human is not ashamed of those things which are morally neutral [indifferentia] or which are not harmful to others. But because intercourse is turned to the detriment of another and frequently to oneself, and similarly because pollution occurs from intercourse, a human is especially ashamed of it.