Questions relating to human freedom cannot be separated from questions relating to human consciousness. The two are intricately entwined, and neither can be understood apart from the other. There is a widespread assumption today that we can understand the nature of human freedom even though there is an equally widespread acknowledgment that we have a lot yet to learn about the nature of human consciousness and its relations to the human body. This separation of the two issues is false. Attempts to prove it have failed and will continue to fail so long as the concept of freedom in its intimate connections with the nature of consciousness is not properly understood. The kind of genuine freedom of thought and action defended in this book lies at the heart of responsible outlooks on our individual and social lives, our hopes for the future, the whole of our history as human beings, and our relations to the natural world.