Every culture rests on a bedrock of folk wisdom handed down through generations. The pronouncements of philosophers are homespun by our grandmothers, and find their way into our common sense: what doesn’t kill you makes you stronger. Do unto others as you would have done unto you. Happiness comes from within.

But are these ‘truths’ really true? Today we all seem to prefer to cling to the notion that a little bit more money, love or success will make us truly happy. Are we wrong?

In The…