Consciousness at sea.

This essay articulates three distinct but interrelated challenges facing evolutionary explanations of consciousness. These are: (i) lingering misconceptions about evolutionary explanations that stem from evolutionary progressivism and adaptationism; (ii) the 'measurement problem,' or the challenge of gathering comparative data on consciousness, as required by any evolutionary accounts, in the absence of not just a theory of consciousness but uncontroversial meta-strategies for coping without such theory; and (iii) unresolved bio-theoretical challenges about how best to individuate traits for the purpose of functional analysis. The effects of these challenges are then illustrated by looking at adaptive accounts of consciousness that pick out valence (provisionally, the goodness or badness of psychological states) rather than phenomenal consciousness (p-consciousness, or the 'something it is like of experience') as the fitness-conferring character. On these accounts, p-consciousness is adaptive only if valence and p-consciousness are parts of the same trait; otherwise, p-consciousness appears to be a byproduct of selection for valence. Whether p-consciousness and valence are part of the same trait in turn depends on how traits are individuated and the relationships between valence and p-consciousness.This article is part of the theme issue 'Evolutionary functions of consciousness'.