“I think most people have one top idea in their mind at any given time. That’s the idea their thoughts will drift toward when they’re allowed to drift freely. And this idea will thus tend to get all the benefit of that type of thinking, while others are starved of it. Which means it’s a disaster to let the wrong idea become the top one in your mind.”

-Paul Graham, “The Top Idea In Your Mind.” paulgraham.com. July 2010

If your top ideas are getting money, arguing with someone, the past, how stupid you are and so forth, then your mind is working on destructive bullshit.