As a boy in late-1940s Memphis, my dad got a nickel every Friday evening to come by the home of a Russian Jewish immigrant named Harry Levenson and turn on his lights, since the Torah forbids lighting a fire in your home on the Sabbath. My father would wonder, however, if he were somehow sinning. The fourth commandment says that on the Sabbath ‘you shall not do any work – you, your son or your daughter, your male or female slave, your livestock, or the alien resident in your towns’. Was my dad Levenson’s slave? If so, how come he could turn on Levenson’s lights? Were they both going to hell?

What have the Romans ever done for us? Well, obviously the roads – the roads go without saying. How about guidance for how to live in the 21st century? That seems less likely, but in fact the last few years have seen a flurry of interest in the work of three Roman Stoic philosophers who offered just that. They were Seneca, tutor to the Emperor Nero; Epictetus, a former slave; and Marcus Aurelius, himself emperor.