I think that when you're young and really smart you think you can reason your way through tough problems because for a lot of problems other people find difficult it's been true. Eventually you'll learn that for many of the toughest problems in life, no clever algebraic trick exists to sort it all out, and you either learn something or you go down the rabbit hole. My first rabbit hole was mortality (I lost sleep for months trying to reason my way around mortality), and my second was simple financial transactions. Relationships, kids, politics, justice -- anything involving other people -- tend to be intractable problems.
One of my "great insights" was figuring out that I didn't understand how I made decisions -- that when I consciously made a decision wasn't when I decided but more like when I became aware that some kind of unconscious tipping point had already been reached. When I have mentioned this to other people I have never ended up in an argument -- they either nod at me as though it's about time I figured this out, or they stop and think about it and agree.
This insight is almost a cliche in matters such as romance, but really it applies to almost everything. When you realize how little we know about our own consciousness, how our rational minds are constantly fooled into thinking they're in charge, the idea we can truly just reason our way out of every kind of problem quickly becomes laughable.
I'm very sad that such a brilliant guy killed himself, but looking at all his blog posts with dewy eyed admiration is morbid, silly, and perhaps even dangerous. Suicide is stupid and -- worse -- selfish. It's not cool or tragic or deep — just sad.
How to be productive, achieve great things, etc.? Hint: do not kill yourself.