Determining the biological function of phenomenal consciousness appears necessary to explain its origin: evolution by natural selection operates on organisms’ traits based on the biological functions they fulfill. But identifying the function of phenomenal consciousness has proven difficult. Some have proposed that the function of phenomenal consciousness is to facilitate mental processes such as reasoning or learning. But mental processes such as reasoning and learning seem to be possible in the absence of phenomenal consciousness. It is difficult to pinpoint in what way phenomenal consciousness enhances these processes or others like them. In this paper, we explore a possibility that has been neglected to date. Perhaps phenomenal consciousness has no function of its own because it is either a by-product of other traits or a (functionless) accident. If so, then phenomenal consciousness has an evolutionary explanation even though it fulfills no biological function.

To compare the options in a decision problem, a common method evaluates for each option the world that would result if the option were realized. This paper argues that one evaluation of an option's world, intrinsic utility, is compositional given a division of an option's world according to the option's consequences and other events. The argument first justifies the norm that an ideal agent should be intrinsically indifferent between two options’ worlds given that she is intrinsically indifferent between the options’ consequences. Then it uses this norm and the existence of intrinsic utilities respecting intrinsic indifference to establish intrinsic utility's compositionality. The results regulate human agents when they approximate ideal agents in pertinent respects. The paper begins with a general explanation of compositionality; the related phenomena of interchangeability, complementarity, and independence; and the effect on compositionality of context and arrangement of a composite's parts. After arguing for intrinsic utility's compositionality, the paper explains its role in decision theory.

Some philosophers say that you do not think in the primary or nonderivative sense. Rather, they say some item distinct from you (perhaps one of your parts or something of which you are a part) does your thinking for you; you inherit your mental life from that item. In this paper, I argue that this is a mistake. We do not inherit our thoughts in this way.

This paper provides a qualified defense of Martin Heidegger's controversial assertion that humans and animals differ in kind, not just degree. He has good reasons to defend the human difference, and his thesis is compatible with the evolution of humans from other animals. He argues that the human environment is the world of meaning and truth, an environment that peculiarly makes possible truthful activities, such as biology. But the ability to be open to truth cannot be a feature of human biology without making such pursuits as biology, mathematics, and philosophy a biological function of a certain species, Homo sapiens. To deny the human difference amounts to species relativism, which leaves the normativity of truth unexplained. To reconcile the human evolutionary heritage and the uniquely human openness to meaning and truth, this paper amplifies a distinction occasionally made by Heidegger between condition and cause.

In this essay I attempt to refute radical solipsism by means of a series of empirical experiments. In the first experiment, I exhibit unreliable judgment about the primeness or divisibility of four-digit numbers, in contrast to a seeming Excel program. In the second experiment, I exhibit an imperfect memory for seemingly arbitrary three-digit number and letter combinations, in contrast to my seeming collaborator with seemingly hidden notes. In the third experiment, I seem to suffer repeated defeats at chess. In all three experiments, the most straightforward interpretation of the experiential evidence is that something exists in the universe that is superior in the relevant respects—theoretical reasoning (about primes), memorial retention (for digits and letters), or practical reasoning (at chess)—to my own solipsistically conceived self.