The title suggests the central claim. Uncle Taleb thinks that we sometimes underestimate the role of luck and randomless in life, mistaking random outcomes for skill or determinism. In the book, Taleb gives concrete ideas as to how this is the case.
My Notes
I picked a few interesting concepts he talked about and will give my thoughts on them.
Lucky Fool: Taleb says that there are people who disproportionately benefit from luck but they attribute their success to their acumen. Such people aren't even consciously aware that they are the lucky fools. Because, by definition, as Taleb says, they are the lucky fools. They genuinely believe their success is due to skill. They just happened to be at the right place at the right time. And their framework for success won't apply to multiple situations. Identifying such people is hard. As the saying goes, "Time is the best judge." Taleb mentioned a few Wall Street traders who essentially went bankrupt after years of success. But if such a person is giving advice, you should also be careful. You can't trust them. Taleb says you can apply the "skin in the game" test: do they have anything to lose if they are wrong?
Survivorship Bias: Oh boy. Taleb was a genius. It is exactly the kind of thing I knew I had to know but didn't know entirely. The idea is profound, yet pretty simple: we study the wrong population. (Well, not always, but for most time). We are only focusing on the winners, and we don't offer even an ounce of attention to the folks who did as much as the winners but ended up not winning simply due to random turns of life. There are a lot of great writers whose work the world doesn't see. And if not for Kafka's friend who publicized Kafka's works despite him intention to get the burnt, the world of literature would be devoid of another great writer. Taleb says it is the doing of an irrational man to obsess over people at the top. The rational men approach any judgement with their, well, rational mind.
These two ideas were my favorite. I ended up actively applying them to my everyday thinking. There were other great ideas, too. One of the best books I've read.