In the quotation, intellectually challenging refers to ideas, not people. Such ideas are interesting, difficult, and satisfying to investigate.

Student or Learner
Does "intellectually challenging" mean "(people like Bill Gates are) intellectually excellent, which poses a challenge for the ordinary"?
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Sam Harris liked
Claire Lehmann
@clairlemon
The vilification of Bill Gates is disturbing. While many people find it easy to understand being motivated by power & greed, the idea that people might do things because they're intellectually challenging & also *good* seems too bizarre to contemplate. Sad reflection of humanity.
In the quotation, intellectually challenging refers to ideas, not people. Such ideas are interesting, difficult, and satisfying to investigate.
I am not a teacher.
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