One of the oddest features of the culture right now is that the philosophy of Stoicism is a big thing. There’s a group called Modern Stoicism which runs a Stoic Week, that asks participants to live like a Stoic — and it turns out that it makes them feel good. In fact, living like a Stoic for a month is even better. There’s a Daily Stoic podcast by the American, Ryan Holiday. There’s an annual gathering called Stoicon for modern Stoics. There are several popular and short guides to Stoicism. And...