in reply to
How do I know what I 'know' is right?
Every abstraction that is not a tautology contains some lie, and is therefore only applicable to some subset of all cases. The better abstractions cover more cases.
So, everything I know is a lie. I should always be prepared to eject any knowledge I have in light of some abstraction that covers more of the territory. It's all models, but some models are better than others.
-- Randal L. Schwartz, Perl hacker
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