> The very name "variable" implies changing value. Variables, both in ordinary mathematics and in the semantics of programming languages, are given meaning by

> The very name "variable" implies changing value. Variables, both in ordinary mathematics and in the semantics of programming languages, are given meaning by substitution, not mutation. This is true even in the semantics of imperative languages[0][1]. [0] https://en.wikipedia.org/wiki/Hoare_logic https://en.wikipedia.org/wiki/Hoare_logic [1] https://en.wikipedia.org/wiki/Predicate_transformer_semantics https://en.wikipedia.org/wiki/Predicate_transformer_semantic...