The discussion so far has provided us with some background to tackle the main question of this book: Are we slaves to our genes? The answer clearly depends on what we mean by ‘slaves’. This in turn takes us into the territory of free will and determinism, a discussion that has been going on for thousands of years, so one that we are unlikely to resolve in one brief chapter. Here our goals will be more modest. Is there an understanding of human identity that does full justice to the latest findings in genetics and which, at the same time, preserves the reality of our profound sense of human freedom? And, at the same time, is there a way of understanding human identity that helps us see how genetic variation can influence human behavioural differences? I think the answer is ‘yes’ to both questions and that’s what this chapter is about.