Apart from roads, sanitation etc, emperor Marcus Aurelius gave us his book Meditations - basically private notes to himself and ideas on Stoic philosophy.
(My book reading technique usually begins by reading quotes via Goodreads, and this often suffices. It's a quick and easy way to get the giste.)
What is Stoicism (capital 'S')?
Imagine you're sitting in a traffic jam, seething. This is not hard for me to imagine. Feels like the worst thing in the world as your mind silently eggs you on - What clown arranged these roadworks? Where are the workmen? No way I'm letting that bloody van in, and so on. Then imagine that you've just run someone over and killed them. Now back to the actual traffic jam: doesn't seem so bad does it.
Similarly, say you're expecting some bad news by post. Every time you hear the postman your heart starts jumping. When the letter arrives you feel sick before you even open it.
Try this: as soon as you know to expect the letter, imagine that it arrives, you open it and it's as bad as can be. Now process this - think how you'll react and what action you'll take in the aftermath. Once you've thought this through, you can park it: when the letter arrives you already know how you'll feel and what you'll do in a worst case scenario, and no need to dwell on it in the meantime.
Our minds are constantly playing havoc with us, but we can train our minds. Every time I learn a little more about this stuff it feels great and improves my perspective on life.
And the quotes from Meditations are definitely worth a look.
P.S. I felt compelled to slip this in...