Enchiridion by Epictetus
This is from 2000 years ago, so it's not clear how much he was of the old greek mindset that life is all about the gods running amok and occasionally running you over. Given his life history (slave with a lame leg), it's easy to see how he could be.
From a public mental health perspective, his flavor of Stoicism seems not great. If you lose a wife or kid, then you should feel some pain, and you want to acknowledge that pain before-hand so that you don't do stupid things that could lead to major losses.
Some things are in our control and others not. Things in our control are opinion, pursuit, desire, aversion, and, in a word, whatever are our own actions. Things not in our control are body, property, reputation, command, and, in one word, whatever are not our own actions.
The book leads with the above fundamental insight of the Stoics: The only thing you own are your actions. In terms of operationalizing philosophy, it's a nice cut / reduction of life's problems. ie., the world is nothing more than a game that you play. Why should those images on the screen make you sad? Or make you happy?
When a raven happens to croak unluckily, dont allow the appearance to hurry you away with it, but immediately make the distinction to yourself, and say, None of these things are foretold to me; but either to my paltry body, or property, or reputation, or children, or wife. But to me all omens are lucky, if I will. For whichever of these things happens, it is in my control to derive advantage from it.
The Stoics' second "insight" is more of a claim: that ataraxia and its impartiality lead to better decisions.1 In order to work this, there has to be an understanding of the range of decision-games that can be played. Given the above public health critique, it does not seem optimal for all of them.
Were he still around, I would ask him what he thought of Egyptian Maat.
Garnier says: Epictetus, born at Hierapolis of Phrygia of poor parents, was indebted apparently for the advantages of a good education to the whim, which was common at the end of the Republic and under the first emperors, among the great of Rome to reckon among their numerous slaves grammarians, poets, rhetoricians, and philosophers, in the same way as rich financiers in these later ages have been led to form at a great cost rich and numerous libraries. This supposition is the only one which can explain to us how a wretched child, born as poor as Irus, had received a good education, and how a rigid Stoic was the slave of Epaphroditus, one of the officers of the imperial guard. For we cannot suspect that it was through predilection for the Stoic doctrine, and for his own use, that the confidant and the minister of the debaucheries of Nero would have desired to possess such a slave.
Never say of anything, I have lost it; but, I have returned it. Is your child dead? It is returned. Is your wife dead? She is returned. Is your estate taken away? Well, and is not that likewise returned? But he who took it away is a bad man. What difference is it to you who the giver assigns to take it back? While he gives it to you to possess, take care of it; but dont view it as your own, just as travelers view a hotel.
When you do anything from a clear judgment that it ought to be done, never shun the being seen to do it, even though the world should make a wrong supposition about it; for, if you dont act right, shun the action itself; but, if you do, why are you afraid of those who censure you wrongly?
When anyone shows himself overly confident in ability to understand and interpret the works of Chrysippus, say to yourself, Unless Chrysippus had written obscurely, this person would have had no subject for his vanity. But what do I desire?