This is a book on European philosophers from Plato to Martin Buber about their way of understanding the world and what it is to be human. The key to this is their experience of thinking. In presenting the ideas of the philosophers I have made the assumption that in successive epochs there is a change in human consciousness and this will mark the way philosophers conceptualize their world and find its meaning. Rudolf Steiner has given rich insights into this change which is an evolutionary one. This must not be confused with the notion of human progress or with a progression of ideas. The biological evolution in which humanity has its place is generally accepted. The evolution of consciousness is in need of recognition and gives insight into our understanding of Greek and Mediaeval Philosophy. It also is a feature of other elements of cultural life. This book offers for the general reader an introduction to the thoughts and perceptions of some remarkable thinkers. In the modern period there is a tendency for philosophy to divide into two streams, one emphasizing observation of the world, the other the experience of the self.