To break up the awkward silence at the start of a recent Overcoming Bias meetup, I asked everyone present to tell their rationalist origin story - a key event or fact that played a role in their first beginning to aspire to rationality. This worked surprisingly well (and I would recommend it for future meetups).
I think I've already told enough of my own origin story on Overcoming Bias: how I was digging in my parents' yard as a kid and found a tarnished silver amulet inscribed with Bayes's Theorem, and how I wore it to bed that night and dreamed of a woman in white, holding an ancient leather-bound book called Judgment Under Uncertainty: Heuristics and Biases (eds. D. Kahneman, P. Slovic, and A. Tversky, 1982)... but there's no need to go into that again.
So, seriously... how did you originally go down that road?
Added: For some odd reason, many of the commenters here seem to have had a single experience in common - namely, at some point, encountering Overcoming Bias... But I'm especially interested in what it takes to get the transition started - crossing the first divide. This would be very valuable knowledge if it can be generalized. If that did happen at OB, please try to specify what was the crucial "Aha!" insight (down to the specific post if possible).
Korzybski and E-Prime are not well-known on LW. LW's ideal of rationalism is an AI which reasons perfectly using the available evidence and whose actions really are optimal for its particular goals. The Sequences are full of introspective tips and behavioral tests for telling whether you're on the right track, so in that sense the philosophy has been given a human form, but the rational ideal which LW humans seek to approximate is described mathematically and computationally, in formulae due to Bayes, Solomonoff, and others. It's a different culture and a different sensibility to what you find in RAW.
By the way, Descartes, Leibniz, and Spinoza aren't so bad, especially if you remember that they created the ideas that we now associate with them. Who wouldn't want to be a creator and a discoverer on that level? Their shortcomings are your opportunity.
I don't know enough about LW's culture to say yet, but for a site--and correct me if I'm wrong--whose "mission" includes taking the "curse" out of "singularity" Robert Anton Wilson's technological optimism strikes me as a great support for such a pursuit...no?