Whatever you define 'good' as, you can still meaningfully ask 'but is that actually good?'

Try to define 'good' as anything else — pleasure, what we desire, what evolution favoured — and Moore pointed out the question 'but is that really good?' still makes sense, which it shouldn't if the definition were correct. He called defining good in terms of some natural property the naturalistic fallacy, and the puzzle still frames debates in ethics over whether moral terms can be reduced to anything else at all.

— G. E. Moore, Principia Ethica — Chapter 1, 1903
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