Question Mark is less of a textbook and more of a picture book, with mind-opening ideas and activities conveyed through words and images working together. The fifteen chapters fall into three parts, corresponding to the three central philosophical skills we want children to develop: questioning, doubting, and being certain. These are fundamental skills that have inspired great thinkers throughout the history of civilization to build and transform the intellectual world.In Question Mark the focus is on asking questions: on thinking about who we are, about reality, and about certainty. The issue is: Can we know anything for certain?  In the story, Mark helps a shadow-rabbit escape from a dog named Dogma, who is trying to eliminate uncertainty once and for all.In the curriculum children are encouraged to think about some of the central tenets of Western philosophy. The teacher manual fills in the historical and philosophical background with references to Socrates, Plato, Aristotle, Hypatia, Descartes, Locke, Hume, Kant, Kierkegaard, Nietzsche, Mill, Dewey, Russell, and de Beauvoir. The glory of the book is that it not only makes this intensely intellectual fare easily comprehensible but also actualizes its affective content so that children can feel the emotional importance of the philosophical concerns.