Boris Hennig

Attempts are often made to explain collective action in terms of the interaction of individuals. A common objection to such attempts is that they are circular: Since every interaction presupposes the existence of common practices and common practices involve collective action, no analysis of collective agency in terms of interaction can reduce collectivity away. In this essay I will argue that this does not constitute a real circularity. It is true that common practices are presupposed in every attempt to explain collective action. However, this does not mean that every analysis of collective action presupposes an understanding of collective action. Common practices do not involve or presuppose particular collective actions. They are more fundamental than individual or collective agency. The subject of a common practice is not a ‘us’ or ‘them’, but the impersonal ‘one’: ‘One does this and that’. What ‘one does’ is not yet a joint activity. It is not a particular action at all.

In this paper, I will discuss a certain conception of matter that Aristotle introduces in Metaphysics Z3. It is often assumed that Aristotle came to distinguish between matter and form only in his physical writings, and that this lead to a conflict with the doctrine of primary substances in the Categories that he tries to resolve in Z3. I will argue that there is no such conflict. In Z3, Aristotle seems to suggest that matter is what is left over when we strip a thing of all its properties. I take it that he does not want us to strip away these properties by physical means or in our imagination. Rather, we are asked to strip a referring noun phrase of all its predicative parts. We are thus not supposed to be able to refer to something that has no qualities whatsoever, but to construct a phrase that refers to something that has properties without referring to its having them, and without implying which properties it has. The idea that there might be a way of referring to something definite without mentioning any of its qualities is platonic and it still underlies modern predicate logic. In Z3, Aristotle argues against this conception and thus against the basic idea of predicate logic. According to him, matter is at best an inseparable aspect of a primary substance, which substance is best referred to as a compound τóδε τι (“this such”). Matter is what the τóδε refers to as part of this phrase. But it cannot exist in separation from form, and we cannot refer to it by a separated term, without also referring to the substantial form of the substance of which it is an aspect

Starting from the idea that functions are formally similar to actions in that they are described and explained in a similar way, so that both admit of an accordion effect, I turn to Anscombe’s insight that the point of practical reasoning is to render explicit the relation between the different descriptions of an action generated by the accordion effect. The upshot is, roughly, that an item has a function if what it does can be accounted for by functional reasoning. Put differently, a part of a system has a function if what it does is a functional part of what the system does.