What sorts of things really exist, in the world or out of it? What can we know about them? How do your thoughts and words relate to reality? What are human beings? What do their freedom and consciousness amount to? How should people act? What would a just society be like? These are the perennial problems of philosophy, which have been examined and debated for thousands of years and are still confronted by philosophers today. In his superb general introduction to contemporary philosophy and its concerns, Anthony O'Hear shows how differing answers to these questions lead to differing conceptions of ourselves and the world.