Seneca, one of the wealthiest men in Rome, regularly practiced poverty. Not involuntary poverty forced on him by circumstance, but deliberate, chosen poverty: a few days each month living on the simplest food, wearing the roughest clothing, sleeping without the comforts his considerable fortune could easily provide. He described this practice in a letter to his friend Lucilius: ‘Set aside a certain number of days, during which you shall be content with the scantiest and cheapest fare, with coarse and rough dress, saying to yourself the while: Is this the condition that I feared?’ The question at the end of...