Osamu Kiritani

The “units of selection” debate in philosophy of biology addresses which entity benefits from natural selection. Nanay has tried to explain why we are obsessed with the question about the meaning of life, using the notion of group selection, although he is skeptical about answering the question from a biological point of view. The aim of this paper is to give a biological explanation to the meaning of life. I argue that the meaning of life is survival and reproduction, appealing to the teleological notion of function in philosophy of biology.

Naturalistic teleological accounts of mental content rely on an etiological theory of function. Nanay has raised a new objection to an etiological theory, and proposed an alternative theory of function that attributes modal force to claims about function. The aim of this paper is both to defend and to cast a new light on an etiological theory of function. I argue against Nanay’s “trait type individuation objection,” suggesting that an etiological theory also attributes modal force to claims about function. An etiological theory of function can be thought to analyze claims about function with modal force, not relying on any theory of counterfactuals.

Evolutionary theory has recently been applied to language. The aim of this paper is to contribute to such an evolutionary approach to language. I argue that Kripke’s causal account of proper names, in terms of natural selection, captures the norm of uses of a proper name, which is to refer to the same object as past others’ uses in a linguistic community. My argument appeals to Millikan’s theory of direct proper functions, which captures the norms of various functional entities in terms of natural selection.

This paper replies to Nanay’s response to my recent paper. My suggestions are the following. First, “should” or “ought” does not need to be deontic. Second, etiological theories of function, like provability logic, do not need to attribute modal force to their explanans. Third, the explanans of the homological account of trait type individuation does not appeal to a trait’s etiological function, that is, what a trait should or ought to do. Finally, my reference to Cummins’s notion of function was intended to note that the homological account is permitted to use this non-etiological notion of function.