IDAH, KOGI STATE, NIGERIA – I am sitting here, my laptop open on my knee, sheltered from the baking sun by a great shade tree in this upcountry village, twelve hours drive inland from Lagos, determined before Christmas to find an answer to that elusive question that has pursued mankind down the ages: what makes for human happiness? There is a good and sensible reason to believe I might uncover the answer here- or at least some of it. The World Values Survey, an inter-university study, recently issued a report in which it found that Nigerians are the happiest people in the world. (The Americans are 16th on their list, the British 24th and the Russians the unhappiest. The survey, which has studied happiness since 1945, finds that it has not increased in Europe and North America even though the societies have become wealthier. The desire for material goods, it concludes,...