"This book is a sustained explanation and defense of the "enactive account" of perception, an approach to explaining perceptual consciousness that Alva Noë has defended in a series of recent papers and in collaboration with others (notably Evan Thompson, Susan Hurley and Kevin O'Regan). The enactive account that Noë defends can look like a radical departure from traditional theories of sense perception that treat perception as a mental state that serves as an input to action and thought but is not itself a kind of action or thought. In several attention-grabbing slogans that appear throughout the book Noë registers his opposition to this psychological division of labor: "Perceiving is something we do," he says, and in Chapter 7 he suggests that it is also "a thoughtful activity". Perception, Noë tells us, is both a kind of action and a way of thinking about the world.
According to the main claim of the enactive account, perceptual awareness depends constitutively on the perceiver's having "sensorimotor knowledge", an implicit understanding of the way sensory stimulation varies with movement. It is this claim that is meant to support the idea that perception is both a kind of action and thought. To get a feel for what Noë has in mind when he talks about sensorimotor knowledge, consider a perceptual event in which you see a ripe tomato. According to the enactive approach, seeing a ripe tomato consists in part in your having a bit of practical knowledge: you must know how the visual stimulation you have would vary if you or the tomato were to move in certain predictable ways. When you successfully see the tomato, you understand implicitly what would happen experientially if you were to move your eyes, or body, or shift your attention, and you also understand what would happen experientially if the tomato were to be moved." - NDPR.