This is post 8/? about the intersection of my decades of LW-style rationality practice and my several years of Zen practice.
In today's installment, I look at equanimity from a rationalist perspective.
In Zen in particular and various Buddhist lineages in general there's a lot of talk about equanimity. Sometimes it refers to a particular meditative state, other times to a more general virtue of meeting the world on equal footing with no particular preconceptions about what one will believe.
It has a so-called near enemy, though, which is indifference, and this is central to the straw stereotype of the advanced Buddhist practitioner you've likely encountered. Think of the unflappable monk who continues to meditate while the building burns down around them, or more likely the idea that through meditation you should become a person who can suppress their emotional responses and never smile, frown, laugh, or cry no matter what the world throws at you. I don't know much about stoicism, but indifference is the same kind of thing people seem to mean when they say that a person is stoic.
Equanimity is something quite different. From the outside it might produce behaviors you could interpret as indifference, especially in training environments like a meditation center or monastery, but in fact it's something more nuanced than that, and something rationalists are quite familiar with.
In everyday language we might say equanimity is about being open to the possibility that the world is just as it is rather than how you think it is, and that whatever thoughts and beliefs you form should not be formed on the basis of what you wish were true but instead on the basis of what you actually observe.
If we focus only on beliefs, equanimity is about being a good Bayesian reasoner, updating fluidly and proportionately in response to evidence. The only thing to watch out for here is that we often model Bayesian reasoning in toy environments where physical reality is constrained to match the model, and Bayesian updating out in the real world includes a lot more uncertainty about the correctness of the fundamental assumptions the model makes than you'll encounter in worked examples.
Thus it may not surprise you that we find equanimity in the Litany of Tarski:
If the box contains a diamond,
I desire to believe that the box contains a diamond;
If the box does not contain a diamond,
I desire to believe that the box does not contain a diamond;
Let me not become attached to beliefs I may not want.
There's some tricky phrases in this litany that I don't quite endorse like "I desire to believe" and "beliefs I may not want", but it conveys the right sentiment and it's part of the rationalist cannon, so it's worth mentioning. The last line mentions attachment, and non-attachment is another thing you might hear a lot about in Buddhism since it's about how to have an equanimous mind. But giving up attachments is a topic for another day.