A world history of morality is maddeningly optimistic

The memory of Tsutomu Yamaguchi will be with me for some time. Though wounded, he survived the Hiroshima atom bomb and returned to his home town, Nagasaki. Three days later, he survived another nuclear attack. He died in 2010, aged 93.

This fat, complex, good-natured and intriguing book is full of such memorable material. Hanno Sauer is a German philosopher with an all-encompassing mind and a capacity to entertain. His arguments are sometimes clogged and improbable and I don’t find his primary thesis – basically that things can only get better – credible, but then I feel the same about most philosophers.

The thesis is based on Sauer’s belief that moral norms are what made us the dominant species and will continue to do so. We share 99 per cent of our genetic material with chimpanzees but, Sauer points out, load a couple of hundred chimps on a plane for a few hours, strap them into uncomfortable seats, feed them bad food and see what happens: ‘There’d be pools of blood on the carpet, torn ears, fingers and penises and countless dead apes.’