If you're a hot startup, investors will offer you money on terms so good it would seem crazy to refuse. And yet it will often be the right thing to. … - Paul Graham

If you work on something you can finish in a day or two, you can expect to have a nice feeling of accomplishment fairly soon. If the reward is indefinitely far in the future, it seems less real.

The inhabitants of all those worlds are trapped in little bubbles where nothing they do can have more than a local effect. Naturally these societies degenerate into savagery.

Something that's obvious in retrospect but I only noticed after years as a primary school parent: kids who are bullies or assholes tend to have parents who are too, and this often makes it hard for the administrators to keep a lid on bad behavior.