Expert definition

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I just came across the following interesting phrase, which is a definition of expert.

The classic definition of an expert is someone who knows more and more about less and less until they know everything about nothing,

The phrase is intriguing because it defines expert under two opposite terms: "more and less" and "everything and nothing", in which expert is an agent who moves from existence (everything) to nonexistence (nothing), from fullness (more) to empty (less). It's very zen-like philosophy: simple and elegant. It's just a beautiful definition I've known.

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