Aristotle claims that just as a builder uses ‘tools’ to build a house, so too the soul ‘use[s] heat and coldness as tools’ to build an animal (Generation of Animals 740b25–34). I consider two questions about this claim: (1) what sorts of things does the soul use, and what is it for things like them to be organized? and (2) what philosophical work does this sort of organization do in Aristotle’s account of animal generation? I argue that the soul needs (...) flexible intermediate agents, that it organizes them in a way that exploits their flexibility, and that this is due to the demands of a complex, multi-stage process directed at a single end. (shrink)

Aristotle’s theory of seed has occupied a very important place in the history of ancient embryology and medicine. Previous studies have overemphasized, in light of the APo. II method, Aristotle’s definition of seed as male semen. In this paper, I wish to show that there are at least three independent definitions of seed working in Aristotle’s Generation of Animals: seed as male semen, seed as female menstruation and seed as embryo. Those three definitions are mutually exclusive on the one hand, (...) but on the other hand, they are also capable of being unified into one Aristotelian account, which can help us understand better Aristotle’s theory of seed. (shrink)

There are two different notions of seed at work in the Generation of Animals: seed as the spermatic residue, which concerns only the male and the female generative contributions, and seed as the kuêma and first mixture of the two generative contributions. The latter is a notion of seed common to plants and animals. The passage in GA I.18, 724b12–22 where Aristotle distinguishes between these two notions of seed has been mistakenly discredited as inauthentic or simply as irrelevant for understanding (...) the seeds of animals. On the other hand, recent studies have rather focused on the seed as spermatic residue, paying little attention to the notion of seed as kuêma. In this paper I defend the authenticity and relevance of this passage and show how understanding the notion of seed as kuêma is essential to have a complete picture of Aristotle’s account of seed. This common notion of seed makes sense of Aristotle’s otherwise puzzling use of the word “sperma” to designate the seeds of plants, the kuêma, the fertilized eggs, and the first mixture of the two generative contributions. It also proves helpful in determining what the word ‘sperma’ stands for in key passages, such as Metaph. IX.7. (shrink)

Ackrill’s Problem is a tension between Aristotle’s alleged view that the matter of a living being is a body that is essentially ensouled, and his view that the matter of a substance preexists its generation. Most interpreters solve the tension by claiming that the subject of substantial generation is not the organic body of the living being, but its non-organic matter. I defend a different solution by showing that the embryological theory ofOn the Generation of Animalsimplies that the organic body (...) of a living being already exists before acquiring the soul in actuality. (shrink)

This paper explores the various ways Aristotle refers to and employs “heat and cold” in his embryology. In my view, scholars are too quick to assume that references to heat and cold are references to matter or an animal’s material nature. More commonly, I argue, Aristotle refers to heat and cold as the “tools” of soul. As I understand it, Aristotle is thinking of heat and cold in many contexts as auxiliary causes by which soul activities (primarily “concoction”) are carried (...) out. This, as I argue, is what it means to call them “tools” of soul. An upshot of this investigation is the fuller picture of Aristotle’s conception of efficient causation it provides in general, and the better understanding of the efficient causal operation of an organism’s nature or soul it provides in particular. (shrink)

Exceptions are often cited as a counterargument against formal causation. Against this I argue that Aristotle explicitly allows for exceptions to essences in his biological writings, and that he has a means of explaining them through formal causation – though this means that he has to slightly elaborate on his general case theory from the Posterior Analytics, by supplementing it with a special case application in the biological writings. Specifically for Aristotle an essential predication need not be a universal predication. (...) Rather an essential predication is where a property belongs essentially to a species or genus. This essential predication serves a causal and explanatory role, and is not dependent on a corresponding universal predication. (shrink)