Have you ever been rock climbing? I assure you that the fact that you're safe, and even the fact that you know you're safe, does not shut off the (untrained) lizard brain, at least not the sort of lizard brain that's afraid of heights.
Bizarrely enough, I went rockclimbing a couple of months ago. The first time in years, and the knowledge that I was safe seemed that it did make a lot of difference. At 50 metres up I deliberately violated the "don't look down" rule because I am somewhat masochistic when it comes to challenging my (miscallibrated) instincts. But the vertigo I expected just didn't come at all - I was genuinely surprised. My theory is that my "lizard brain" was already engaged with my rather stronger competitive instincts.
I find the same thing. Climbing isn't scary at all when you're tied on.
ETA: There is now a third thread, so send new comments there.
Since the first thread has exceeded 500 comments, it seems time for a new one, with Eliezer's just-posted Chapter 33 & 34 to kick things off.
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