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by Kutta 3407 days ago
Evaluation is always implicitly used in any sort of mathematical formalism. "2 + 2" is a program which evaluates to "4". Type theory just makes the computation arising from substituting definitions rigorous. Not letting "2 + 2" be equal to "4" by definition would be weird and inconvenient.
1 comments

I get that evaluation is always implicit (or at least implicitly assumed to happen). My quarrel is with "evaluation == program == computation", and even more with the reverse: "a number == computation that would produce the number, therefore number == computation".