1. SEXUAL DIFFERENCE

For Aristotle sexual differences arise from the heart’s nutritive function in some animals (GA IV.1.766a30–b5). These animals concoct (pettein) the food they ingest into blood, which serves as an internal nutrient for the entire body (PA II.3.650a2–8; II.4.651a12–17; Meteor. IV.2.379b18–380a10). The residue (perittōma) of the final stage of concoction is the animal’s seed (sperma, GA I.18.725a11–15). Concoction requires heat; therefore, the colder the animal, the less perfectly it concocts (Meteor. IV.2.380a6–9; GA II.1.733a32–733b16). Since female animals have less heat than their male counterparts, they are incapable of concocting a seed to perfection (GA IV.1.765b10–22; 30–766b3). Evidence that females are colder includes (1) that their less-concocted residue, the menses (katamēnia), resembles blood (GA I.20.728a26–29) and (2) that they excrete some of the blood men use for nutrition and growth, making them smaller and weaker (GA I.19.726b30–727a2, 727a18–25).

This evidence is controversial because Aristotle acknowledges that not all female animals have menstruation (GA I.20.728a1–2), nor are they all weaker than their male counterparts (HA V.11538a24–28; GA I.16.721a17–20). However, Aristotle offers methodological arguments in support of a theory of sexual difference strongly based on humans: humans are more familiar to us (HA I.6.491a20–23) and more complete than other animals (HA IX.1.608b4–8). Thus, he considers women to be the paradigmatic case and other female animals to be analogous to them (Leunissen, pp. 242–3). This leads him to refine his point by distinguishing between secreted and internal menses. Only moister animals, like humans, have the former, but all have the latter (GA I.20.728a36–b7). In sum, according to Aristotle, the female is defined by her incapacity and the male by his capacity to concoct to perfection (GA IV.1.765b15–21). Within the scope of her book Leunissen (p. 73) only considers this material explanation of sexual difference.

However, this is half of the story. Aristotle also explains sexual difference in terms of final causes (Connell, p. 2). GA II.1.731b20–732a11 states that male and female animals exist for the sake of generation, according to the metaphysical principle that the superior should as far as possible be distinct from the inferior. Consequently, sexual differentiation is a characteristic of more perfect species (HA IV.11.537b22–538a7). Since the cause of motion is superior to that which suffers its effects, the male is superior because he is a principle of motion. The female is inferior because she is the matter of generation or the place where generation occurs (PA II.2.648a11–13; GA I.2.716a4–23).

García-Peláez (p. 71) relates this teleological explanation to DA II.4.415a25–b10 and claims that the final cause of sexual differentiation – whose end is reproduction – is the eternity of species. Sublunar living beings cannot have the perfect life of supralunar beings; thus, they resort to reproduction to achieve the only kind of immortality open to them: the eternity of their species (p. 75). Females exist to contribute to both the physiological processes of generation and the noble metaphysics of generation (p. 41). By incorporating biology into the cosmos, García-Peláez (p. 31) concludes that being female involves ‘la operación más noble de las capacidades fisiológicas de los seres vivos’ (p. 81). She thus agrees with Connell (p. 4), who maintains that, despite their material incapacity for concoction, no imperfection befalls female animals (GA I.1.715a20–21; II.4.737b10–12).

2. SEX ROLES IN REPRODUCTION

The previous section argued that the difference between a material and a teleological account of sexual differentiation allows Aristotle to grant female animals a relevant natural function despite their material limitations. This section addresses the female’s limitations in performing this reproductive function. Although both male and female animals produce seeds, there is an important caveat. Aristotle argues that it is the presence of a special kind of hot air, the pneuma (‘soul-heat’), that makes a seed in fact a seed (GA II.2.735b25–736a2; II.3.736b33–737a1). Because only male seed has this pneuma, only the sperm (gonē) is strictly a seed (GA II.3.737a7–8). Consequently, the female ‘seed’ becomes only analogous to a seed and is simply matter (GA I.19.727a2–5, 25–30). The controversy over the contribution of each sex to reproduction partly stems from Aristotle’s ambiguous use of the term sperma (‘seed’), but the problem is not merely a matter of terminology. Aristotle acknowledges that he must explain how characteristics of the mother (and grandmother) are transmitted to the baby (GA I.17.721b20–24). How can this transmission occur without a female seed? Our authors offer different interpretations of Aristotle’s response to this question.

Leunissen (p. 65) proposes the ‘material inheritance theory’. According to her, semen and menses resemble all the body parts of the animal producing them because they are a residue of nutrients meant to go to all these parts (GA I.18.725a21–28). In other words, they both contain what we call genetic information – the resemblance of body parts –, which Aristotle describes as the parent’s characteristics in potentiality (GA IV.3.768a13–14). Thus, even though menses are merely the matter of the embryo, they also impart genetic information. Semen, in turn, provides both genetic information and form-imparting motions, i.e. the activation of life as the form of that species (Leunissen, p. 79). Although Aristotle warns against taking this metaphor too far (GA IV.4.772a22–25), Leunissen (p. 79) argues that an embryo develops similarly to how cheese is produced (GA I.20.729a12–14), with milk as the matter and the curdling agent as the form provider.

Based on Aristotle’s assertion that semen does not become part of the new animal (GA I.22.730b9–32), García-Peláez (p. 135) posits that the mother furnishes all the matter necessary for the development of the new animal (GA I.19.727b31–33). This challenges the notion that genetic transmission can be material. Instead, she supports a ‘dynamic’ account of Aristotle’s embryology (p. 176). According to her (p. 158), Aristotle believed that both parents contribute seeds capable of generating body parts (GA II.3.737a22–24). The only difference between the two is the additional functions they serve in the process: semen triggers the development of life, while menses supply the necessary matter (GA I.2.716a4–6). She provides four pieces of evidence for this claim.

The first is Aristotle’s statement that the female residue is the one endowed with the power to produce both the male and the female reproductive organs (GA II.3.737a24–25). From this García-Peláez infers that it constitutes a ‘dynamic matter’ (p. 176), which contributes to the teleological motion of generation rather than passively participating in it. The second piece of evidence is Aristotle’s claim that, when the male seed fails to impose its form on the female seed, a new female animal is generated (GA IV.3.767b9–11). García-Peláez interprets this as Aristotle acknowledging that the female seed counters the male seed’s power with its own power (p. 188), which stems from the female seed’s actual properties as a seed (p. 176). The third and fourth pieces of evidence are Aristotle’s explanations of two special phenomena: wind eggs and molar pregnancies. In two passages (GA II.5.741a16–31; III.7.757b14–30) Aristotle describes wind eggs as having a nutritive soul, but lacking a sensitive soul, which can only develop with the triggering of the male seed. Since in HA X.7.638a21–25 Aristotle compares molar pregnancies to wind eggs, García-Peláez (p. 185) concludes that the female seed contributes the nutritive soul in all animals, which she calls ‘el primer pneuma’ (p. 154). Therefore, these two phenomena would prove that, although the nutritive soul is insufficient to generate an animal, female contribution to embryology is active, not passive.

Leunissen maintains that, according to Aristotle, women do not contribute strict seed. Instead, she argues (pp. 177–9) that Aristotle believed that some of the air around us could circulate in our body. Thus wind eggs (HA V.5.541a26–31; VI.2.559b20–28, 560a5–20), false pregnancy symptoms (HA VII.4.584b18–25) and molar pregnancies (HA VI.18.572a8–22; VII.4.584b18–25) were allegedly caused by wind entering the womb instead of male seed (pp. 176–88). Leunissen’s position on HA X is more nuanced. She claims that the chapter – including the discussion of molar pregnancies in X.3.636a9–26 – is not Aristotle’s work, but rather a medical treatise titled On Sterility that was incorporated into the Aristotelian corpus. However, she (p. xx) believes that HA X.7 may be a Peripatetic inclusion. In Leunissen’s reading (pp. 219–20), this text offers two explanations for molar pregnancies. The first explanation (HA X.7.638a10–b1), which attributes the condition to heat in the uterus drawing in the menses, is comparable to wind eggs, but is ultimately rejected by the author. The second explanation, endorsed by the author, is that the moisture in the uterus simmers the menstrual blood for a long time, preventing its expulsion (HA X.7.638b1–37). In sum, Leunissen claims that these phenomena are not caused by the power of the menses, but rather by environmental influences.

These opposing views illustrate how far we are from reaching a consensus on Aristotle’s embryology, largely due to the diversity of arguments within the text.

3. BEING BORN A FEMALE

The ongoing embryological debate has consequences for the interpretation of Aristotle’s account of the determination of an embryo’s sex. He states that, when the semen is unable to concoct the whole menses to its proper form, the embryo becomes a female animal (GA IV.1.766a18–22; IV.3.767b8–13). Thus, the female is the product of a less successful concoction due to the lack of heat (Meteor. IV.1.379a1–3; 2.380a6–10). Our authors disagree on what causes this colder temperature.

García-Peláez (p. 121) claims that, in Aristotle’s view, the less successful concoction is due to the power of the menses to constrain the teleological activities initiated by the semen (GA IV.1.766a18–22). Concoction lacks heat because the cold of the female seed overpowers the heat of the male seed. This makes her point that female embryological residue has an active power and is indeed a seed. While the power of the female seed may seem to bring Aristotle closer to the contemporary understanding of embryological processes, it also leads to conclusions that are foreign to it. Notably, the characteristic power of the female seed is to create teleological failures (García-Peláez, p. 128). The birth of a female animal is a deviation from nature caused by anankē, the constraint that comes from the power of matter (GA IV.3.767b4–13; IV.10.778a4–9; PA III.2.663b29–35). Moreover, this is only the first stage of deviation. If left unbridled, the power of female seeds can cause the generation of monsters (GA IV.3.767b13–15; IV.4.770a6–7).

According to Leunissen (pp. 189–98), Aristotle argues that the presence of cold during concoction is caused by either the semen or the environment. GA IV.2.766b29–34 links the birth of female animals to parents being too young and lacking sufficient heat or being too old and having lost heat. It also asserts that cold can come from bodies that are more feminine, which are moister and have less thick semen. The reference to semen in the second type suggests that the age factor also applies to male parents. Thus, Leunissen (p. 190) concludes that females are born due to the properties of male seed. However, there are other causes involved. Aristotle attributes the majority of female births in certain populations to environmental factors, such as winds (GA IV.2.766b34–767a1), moist surrounding air (GA V.3.782b33–783a1), geographical orientation (GA IV.2.767a8–13) and water quality (HA VI.19.573b32–574a4; GA IV.2.767a28–35).

Leunissen (p. xiv) acknowledges Aristotle’s mistake concerning female embryology and aims to explain why he was so wrong. She provides three explanations. First, embryological information was inaccessible to observation; thus, Aristotle relied on medical treatises for expert accounts (p. 54), engaging in a type of armchair research (p. xx). When Aristotle embarked on this second standard of research, he was not committed to the truth of these claims, only their ontological possibility or sufficient credibility (pp. 16–17). Second, most of his embryological arguments are part of a dialectical discussion against the pangenesis theory, which posits the existence of both male and female seeds. In arguing against their position, he was led to defend the non-existence of a female seed by offering an explanation without first establishing the facts (pp. 63, 82). He was probably comfortable doing so because the facts were inaccessible to observation. The third reason is his commitment to the principle of nature’s economy, according to which two organic parts should not perform a single (reproductive) function (p. 68). In my view, the third reason reveals the problem with this methodological ‘second sailing’. Ultimately, Aristotle measures the credibility of explanations against his teleological principles (Leunissen, p. 29); so ontological possibility entails a common ground between the expert’s account and Aristotle’s concept of nature. Therefore, even if Aristotle were right in denying the existence of female seeds, his methods for making this claim would be circular.

4. SEX AND GENDER

While no one would claim that Aristotle was aware of the modern distinction between sex and gender, his works raise questions about how far he went in identifying the two when justifying social roles based on the biological aspects of human beings. One example of Aristotle’s juxtaposition of sex and gender is his claim that different capacities for concoction result in different blood qualities. Males’ ability to concoct perfectly gives them thicker blood, which makes animals stronger (PA II.2.648a2–4). This may relate to Aristotle’s assertion that females are less spirited (athumotera) than males (HA IX.1.608a33–b18). This statement is also threatened by false generalisations about animals and is again explained by the paradigmatic role of human beings (HA IX.1.608a21–24).

Connell (p. 15) suggests that thinner blood makes women more stable and sensitive, with a better memory and greater learning capacity, though this can result in cunningness (PA II.2.648a2–4; HA IX.1.608a25–b18). She also claims that, although Aristotle lacks a non-circular explanation for the overlap between sex and gender, he explains the subordination of women as being due not to any intellectual incapacity (p. 45), but to their lack of spirit – particularly the kind that is wild and dominating (pp. 35, 55). Consequently, women can neither control men nor act without their approval (p. 48). Moreover, Aristotle argues that this kind of spirit is required for someone to either rule or be free (Pol. VII.7.1328a6–7). Thus, men are more fit to command than women (Pol. I.12.1259b4–10). This aligns well with the aforementioned teleological principle, which posits that men are superior to women (GA II.1.731b20–732a11; DA III.5.430a18–19; Pol. I.5.1254b13–16; VII.14.1332b32–34; Connell, pp. 45–6).

García-Peláez (pp. 114–15) agrees that sexual differences entail differences in character. However, these differences are not necessarily based on spirit but rather on functional assignments (p. 106). She argues that, according to Aristotle, castrated animals and eunuchs become womanlike due to their inability to reproduce (GA I.2.716b3–12; IV.1.766a21–30; V.3.784a6–11; V.7.787b19–788a16). According to this view, sex and gender depend on the physical and behavioural capacities of the individual (p. 111), resulting in sexual differentiation being procedural (p. 131). Conversely, García-Peláez (p. 19) claims that biological factors alone cannot provide Aristotle with a valid explanation for his assertion that women should obey men. Although the metaphysical account of reproduction may give women some value in Aristotle’s eyes, García-Peláez (p. 222) submits that it never justifies Aristotle’s arguments for gender inequality.

5. WOMEN’S INTELLECTUAL CAPACITY

In the previous section I mentioned Connell’s claim that Aristotle never attributes intellectual incapacity to women (p. 45). Connell identifies sufficient evidence to support Aristotle’s commitment to the thesis that ‘women are human, free, intelligent, and ought to be virtuous and happy’ (p. 19). First, this statement must be qualified. As Connell (pp. 10–11) acknowledges, Aristotle endorses the view that some women are natural slaves who will never be, nor should be, free (Pol. I.IV.1254a7–17). Thus, according to Aristotle, there are natural differences that distinguish human beings in a more fundamental way than sex.

Next, Connell (pp. 24–5) grounds her assertion regarding the virtue of women and the happiness it brings in Aristotle’s analysis of friendship. EN VIII.12.1162a25–27 states that wives are capable of being good (epieikēs) and sharing with their husbands the superior kind of friendship. However, Aristotle also states that this type of friendship involves one party being superior (EN VIII.7.1158b11–14) and that a wife’s virtue lies in obedience (Pol. I.12.1260a20–24). Therefore, the claim that wives ought to be virtuous and happy does not necessarily imply that their virtue is the same as their husbands’ and that their happiness is not a pis aller. Aristotle expressly disagrees with Socrates’ view that the virtues of men and women are the same (Pol. I.13.1260a20–23).

Before proceeding, a note must be made on Aristotle’s most infamous statement, which I quote in Connell’s translation (p. 20): ‘The slave is completely without the deliberative capacity, the female has it, but it has no authority (akuros), the child has it, but undeveloped’ (Pol. I.13.1260a13–14). Connell (p. 42) defends the idea that akuros should be read interpersonally due to its political meaning (Pol. IV.14.1298a3–6). Accordingly, women’s deliberation is only ineffective externally (p. 35), due to their incapacity for public deliberation (p. 43), ultimately resulting from their lack of spirit (p. 45, see Section 4). Nevertheless, proof of their deliberative capacity lies in their effective decision-making within the household (p. 24). Therefore, according to Connell, this statement essentially claims that women lack political authority, yet possess domestic authority (p. 32). I fail to see how this can correspond to the text. If the deliberative capacity that women exert effectively refers to the household, the negative statement must refer to the same realm: the wife does not have [domestic] authority. Setting aside the controversy, one point seems certain: that, although Connell’s translation of thēlu as ‘female’ – García-Peláez (p. 13) opts for ‘woman’ – is technically correct, the argument does not allow for this inclusiveness. Not every woman is in a position to exercise her deliberative capacity. Connell (p. 58) agrees that Aristotle’s comments on women in his practical philosophy are directed to free wives.

I insist that the infamous statement refers to wives’ expertise in domestic tasks because nowhere does Aristotle explicitly ascribe to women in general a knowledge that is not functional, a virtue that is not obedience or an intellectual capacity for a contemplative life. On the other hand, their intellectual competence for certain expertise is attested. For instance, Leunissen (pp. 160–7) demonstrates how Aristotle acknowledges women’s expertise in midwifery. HA VII.10.587a9–24 provides evidence of their knowledge of how to cut the umbilical cord, how to assist with difficult births, how to resuscitate newborns and how to respond to unexpected situations. Leunissen (p. 169) also refers to two terms that Aristotle explicitly claims were coined by women – prophoros, the placenta (HA VII.7.586a29–30), and mēkōnion, the meconium (HA VII.10.587a30–31) –, which were most likely technical terms established by midwives. This recognises their specialised knowledge.

That being said, I remain sceptical about Leunissen’s assertion that Aristotle ‘accepts women’s epistemic authority concerning gynecological phenomena, and treats them as reliable knowers about their own bodies and experiences’ (p. xxv). The evidence she provides is controversial. HA VII.3.583a14–15 states that ‘a sign occurs in women that conception has taken place’. In HA VII.4.584b6–14 Aristotle claims that, since babies born at eight months do not survive, whenever one does survive, it is assumed that the woman conceived earlier than she realised. In my view these passages are insufficient to conclude that Aristotle relied on women as knowers of their own bodies and ‘the timing of conception and the duration of their pregnancies’ (p. 128). On the contrary, the second passage states that women miscalculate the duration of their pregnancies, which contradicts the first passage, according to which women know the time of conception. Leunissen claims that, in this case, he ‘gently corrected women’s beliefs’ (p. 176), but this seems sufficient to refute the idea that he preserved ‘the authority of women as those who generally present reliable knowledge’ (p. 163).

Leunissen persuaded me that in his ‘armchair research’ (see Section 1) Aristotle relied on medical treatises reporting ‘mistaken folk-beliefs shared by women’ and ‘old wives’ tales’ (pp. 126–7). She astutely points out that medical writers may report information given by women to ‘magnify their own epistemic authority’ (p. xx), while expressing doubts as to whether these reports are legitimate (see ‘allegedly’ on p. 85 and ‘male bluff’ on p. 151). However, I believe that the question of whether Aristotle accepted these reports because women and physicians gave them a ‘double epistemic authority’ (p. 129) remains controversial. It seems more plausible that Aristotle used physicians’ reports as ‘proxies for women’s own authority’ (p. 248). One of Leunissen’s theses is that Aristotle was wrong about women due to ‘his uncritical acceptance of certain facts about women, even though they are patently false’ (p. 130). Ultimately, this seems to blame women for Aristotle’s mistakes. However, if Aristotle chose to take medical treatises, with their ‘male bluff’, as a reliable source instead of the expertise of the midwives, perhaps it was because he doubted female intellectual capacities.

Scholarship in the wake of the second wave of feminism identified the roots of patriarchal philosophy in Aristotle’s work and denounced it. The books reviewed represent a new trend and provide a valuable service by moderating these accusations. Nevertheless, Aristotle’s text remains controversial, and we should welcome an ongoing debate that sheds more light on these important issues.