"I know I am conscious: I am seeing, hearing, feeling something here, inside my own head. But is consciousness—subjective experience—also there, not only in other people's heads, but also in the head of animals? And perhaps everywhere, pervading the cosmos, as in old panpsychist traditions and in the Beatles' song? While these kinds of questions may seem scientifically inappropriate, we argue below that they can be approached in a principled and testable manner. Moreover, obtaining an answer is urgent, not only because of difficult clinical cases and in our interactions with other species but also because of the advent of machines that are getting closer to passing the Turing test—computers programmed to perform many tasks as well as us, and often far better than some brain-damaged patients."