The difference for present purposes between ourselves and stones, chairs and our computers is that we are conscious. The difference is fundamental. Being conscious is sufficient for having a mind in one sense of the word ‘mind’, and being conscious is necessary and fundamental to having a mind in any decent sense. What is this difference between ourselves and stones, chairs and our computers? The question is not meant to imply that there is a conceptual or a nomic barrier in the way of non-biological things being conscious. It may happen one decade that the other minds problem will shoot up the philosophical agenda and get a lot of attention as a result of a wonderful computer attached to perceptual and behavioural mechanisms, and that the thing will in the end be taken as conscious, rightly. Our question is not what things can be conscious, but what the property or nature of consciousness is.