One of the hardest things about writing on what might be called a ‘special interest’ must be convincing potential readers that you are not going to preach at them. Rest assured. Tristram Stuart doesn’t preach. What he does do is try to make us think about what we eat, and why, and what effect our choice of diet has on ourselves, the animal world, and the ecology of the planet. And, in spite of his misleading subtitle, he succeeds triumphantly. ‘Radical Vegetarians and the Discovery of India’ suggests a claim to spectacular achievement on the part of a fringe group trying to enhance its credentials. In fact The Bloodless Revolution is a scholarly, wide-ranging and utterly absorbing history of vegetarianism. 

Although the word ‘vegetarian’ was not coined until the 1840s, as long ago as the sixth century BC Pythagoras propounded a theory of immortality that entailed the transmigration of the soul between living creatures – and thus the immorality of eating the flesh of any of them. Pythagoras was thought