Edit: in fact the letter I read yesterday was, like the one posted here, on life. Some things I liked from it:
"...death ought to be right there before the eyes of a young man just as much as an old one. [...] Every day, therefore, should be regulated as if it were the one that brings up the rear, the one that rounds out and completes our lives."
"To live under constraint is a misfortune, but there is no constraint to live under constraint."
"Whoever has said 'I have lived' receives a windfall every day he gets up in the morning."
When I was a kid, I learned from observing my father that being a "real man" means shaping the world according to your view of how it should be-- taking control, avenging wrongs, showing strength. In my 30's and 40's I've been totally reshaping my ideal of what a real man does, and it involves the opposite in many ways: making people feel safe, having excellent self control, and outstanding control of my emotions and attitude. The shocking thing to me is how often the behaviors I know as right according to my new ideals make me behave in ways that my father would see as pathetic and weak.
But it's completely possible to re-train one's own emotional composition and approach to life. That's what Stoicism is all about. I wish someone had taught me about this when I was young. A few things I wish I'd known about when I was a kid:
1. The No Complaining bracelet challenge. This was life changing to me, because through this exercise I learned that "letting it all out" doesn't really help much, and what really helps is reshaping your own mind. I'm still doing this challenge today, as a life habit, even after several years.
2. Stop worrying and stop living. You can boil this book down to a few pages, with a lot of stories that help you understand why and how. I did this book on audio during a long car trip. Also life changing for me.
3. Stoicism. Reading Letters from a Stoic taught me that there was an entirely different way to look at friendship that I'd never considered. And it taught me that there are people who constantly practice controlling their emotions in a positive way, the way a martial artist constantly practices how to move his body.
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