There is a paradox at the heart of our lives. Most people want more income and strive for it. And yet, as our societies become richer, people get no happier.

This is no old wives’ tale. It is a fact, proven by countless pieces of scientific research. We now have many good ways to measure how happy people are, as I’ll show, and all the evidence tells us that on average people have grown no happier over the last fifty years. At the same time, though, average incomes have more than doubled. This paradox is true for the United States, Britain and Japan.

But aren’t peoples’ lives infinitely more comfortable? Indeed: They have more food, more clothes, more cars, bigger houses, more central heating, more foreign holidays, a shorter working week, nicer work, and, above all, better health. And yet they are not happier. Despite all the efforts of governments, teachers, doctors, and businessmen, human welfare has not improved.

This devastating fact should be the starting point for all discussion of how to improve our lot. It should cause every government to reappraise its objectives and every individual to rethink his or her goals.

One thing is clear: Once subsistence income is guaranteed, making people happier is not easy. If we want people to be happier, we really have to know what conditions generate happiness and how to cultivate them. That is what this book is about—the causes of happiness and the means we have to effect it.

We do not know all the answers, or even half of them. But we have a lot of evidence—enough to rethink government policy and to reappraise our personal choices and philosophy of life.

The main evidence comes from the new psychology of happiness. But neuroscience, sociology, economics, and philosophy all play their part. By bringing them together, we can produce a new vision of how we can live better—both as social beings and in terms of our inner lives.