More than anything else, that paragraph is what kept me coming back when I first started learning to program and struggled mightily. I lugged that huge book around in my book bag for months, trying and failing to fully grok one of the earlier chapters, until I found a professor who was willing to help me with it. Ultimately we (the professor and I) were able to do a one semester independent study focusing on the material from SICP.

I used to read and re-read that paragraph. I read it aloud to my parents and to girlfriends, trying to find somebody to share my awe.