Phenomenal consciousness: its scope and limits.

In the history of life, consciousness of sensory states with 'phenomenal properties'-the basis of 'sentience'-is, arguably, a late evolutionary development, which occurred long after conscious access to a 'global mental workspace' had become widely established as a strategy for cognitive information processing. In this article, I focus on phenomenal consciousness. I propose a step-by-step sequence by which the mental representation of sensory stimulation could have acquired phenomenal content through small changes in the brain. Also-addressing the question of evolutionary function-I point to the crucial psychological benefits to an animal of having a 'phenomenally conscious self'. A thread running through the article is the phenomenon of 'blindsight', which I take to be a model for the non-phenomenal cognition that characterizes the majority of insentient animal species.This article is part of the theme issue 'Evolutionary functions of consciousness'.