Some people think that the impulse to philosophise begins in early childhood: Gareth Matthews, for instance, in his Philosophy and the Young Child (1980). His book begins ‘TIM (about six years), while busily engaged in licking a pot, asked, “Papa, how can we be sure that everything is not a dream?’” ‘Tim's puzzle,’ he tells us, ‘is quintessentially philosophical. Tim has framed a question that calls into doubt a very ordinary notion (being awake) in such a way as to make us wonder whether we really know something that most of us unquestioningly assume we know.’