@c531994e that’s a good framing. I would also be afraid of exposure to falling but not heights. Flying in a plane doesn’t scare me. Obviously you could crash, but statistically, it is a very low risk. Me walking/climbing on edge of a cliff, falling is not such a low risk. 

 @d4d25d16 I am listening to the book now! I usually prefer to read, but NYPL had audiobook available only. Super interesting and informative!