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If the first casualty of war is the unwelcome truth, the first tool of the discontented is the welcome lie. Such lies cluster freely around Thomas Aquinas. Here I want to engage two frequently encountered in feminist literature: that he claims women are defective males and that he claims that the male human embryo receives a rational soul earlier than does the female. Aquinas nowhere makes the second claim, and as for the first, not only does he not assert it, he denies it no fewer than six times.

One may wonder why he should find it necessary to deny that woman is defective. The answer lies in Aristotle, who, in his account of reproduction, writes that “the female is as it were a defective male.” As a Catholic theologian, Aquinas believes that God personally produced the first woman. She cannot therefore be defective. Yet Aristotle’s name in the Middle Ages evoked all the awe that Einstein’s does in our own. What he said about the female—or anything else—would be taken very seriously in the medieval universities. Aquinas therefore diplomatically attempts to set Aristotle’s dictum in its context and to show that it has a strictly limited application which does not imply that women are defective.

Aristotle’s theory of reproduction correctly identifies semen as the male reproductive substance. But he does not know about the existence of the ovum—that had to await the researches of William Harvey, the seventeenth-century Englishman who also discovered the circulation of the blood. Aristotle thinks that the female reproductive substance is a very pure fraction of the menstrual blood. Both substances, he says, are produced by the body in a process of “concentration” that requires heat. The male substance, the semen, is more concentrated than the female substance. Aristotle concludes that the male possesses more heat than does the female. The female, accordingly, is relatively lacking in heat, and this is the meaning of the statement that the female is a defective male. It is, as can be seen, a very limited statement, and has no more general significance than the assertion that women lack the muscular power of men.

Aristotle, however, has more to say. He thinks that the male semen seeks to “master” the female reproductive substance and to cause it to develop into a male child. But sometimes—manifestly on some 50 percent of occasions—the semen itself is “mastered,” either because it is weak or because the female substance resists its action, or for some other reason. Then a female child is born. In other words, the female child is not what the male semen “intends,” and arises from some failure in the action of the semen.

To be fair to Aristotle one must add that for him this failure is built-in by nature, for both females and males are required if animals are to reproduce and continue the species. The female is not truly defective, but only as it were defective.

Aristotle’s phrase “the female is as it were a defective male” came to the Scholastics in the translation femina est mas occasionatus. Occasionatus is a word not found in classical Latin. The Scholastics use it to mean something caused unintentionally or accidentally. Now accidents, by and large, are for the worse, so much so that when they are for the better, we talk of a “happy” accident. The phrase therefore implies that there is something deficient in the female.

Aquinas, as has been said, takes the matter so seriously that he deals with it no fewer than six times. The main treatment is in his Summa Theologiae (1, 92, 1). The problem comes up when he is dealing with the creation of the world. He asks whether God should have created woman at the beginning of the world. Although the manifest answer to this is Yes, Aquinas nevertheless states some objections to this answer. The first objection is that Aristotle has said that the female is an “unintended” (occasionatus) male, and what is “unintended” is defective. It follows that woman is defective. Now God should not have made anything defective at the beginning of the world, and consequently He should not have made woman.

Aquinas answers the objection as follows. The female may not be intended by the male semen, but it is most certainly intended by nature. And since God is the author of nature, the female is intended by God. Being intended, it is not defective. Hence God rightly made woman at the beginning of the world.

With respect to the particular nature the female is something defective and occasionatum, for the active force in the male semen intends to produce a perfect likeness of itself in the male sex; but if a female should be generated, this is because of a weakness of the active force, or because of some indisposition of the material, or even because of a transmutation [brought about] by an outside influence . . . . But with respect to universal nature the female is not something occasionatum, but is by nature’s intention ordained for the work of generation. Now the intention of universal nature depends on God, who is the universal author of nature. Therefore, in instituting nature, God produced not only the male but also the female.

The passage requires some comment. The phrase “with respect to the particular nature the female is something defective” may suggest to ears unused to scholastic language that the particular nature of the female is defective. But “particular nature” means the power or force in a particular thing, and here the particular nature is the power in the male semen. There can be no doubt on this point, for in his Summa Contra Gentiles (3, 94) Aquinas explicitly states that the particular nature is the power in the semen.

The phrase that the female “is by nature’s intention ordained for the work of generation” must not be taken to mean that the male is not so ordained. Aquinas argues explicitly in the same article that both woman and man have more important things to do than to procreate. Their primary task is to know and understand the world in which they live. Indeed the reason the sexes are distinct is precisely so that individual people can explore the world in their own way.

One may note the meaning Aquinas gives to the Genesis statement that the first woman was formed from the side of the first man. Woman, he says, (Summa 1, 92, 3) was not formed from man’s head, because she should not dominate him. Neither was she formed from his feet, for she should not be despised by man, as though she was subject to him as a servant. Rather she was made from his side so as to signify that man and woman should be conjoined as allies (socialis coniunctio).

The mistaken attribution to Aquinas of the view that the male embryo receives a rational soul earlier than the female also arises from a commentary on Aristotle. Aquinas cites (In 3 Sent., 3, 5, 2, co et ad 3) a passage from Aristotle’s History of Animals which says that if an embryo is aborted, the articulation of the male can be perceived at forty days, that of the female after ninety days. He cites the passage because he wishes to argue that the body of Christ was complete in every detail, even if tiny, from the moment of conception, whereas other embryos are only gradually articulated. Neither in Aristotle’s original statement nor in Aquinas’ comment on it is there any reference to the infusion of the soul. There are more than fifty passages elsewhere in Aquinas where he does refer to the infusion of the rational soul. In none of these passages does he make any distinction between men and women.

All in all, then, those searching for evidence that Christianity has viewed woman as defective to man will have to look elsewhere than to Thomas Aquinas.

Michael Nolan is Professor Emeritus in the Maurice Kennedy Research Center at University College, Dublin.

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