OOP's got a similar problem: When the idea was originally dreamed up, message passing was an essential part of the definition. This wasn't an arbitrary thing, m

OOP's got a similar problem: When the idea was originally dreamed up, message passing was an essential part of the definition. This wasn't an arbitrary thing, message passing was a precondition of the characteristics that people were trying to achieve in the first place. Nowadays, the definition's been deeply watered down, and there are vanishingly few languages that both call themselves object oriented and stick to the original idea. So maybe it's not worth fighting over the terminology anymore. But still, I can't help but feel like we've lost something in the process. FP didn't become the darling until more recently, and I think that it's just possible that people could hold the line and prevent the term from being watered down. And the original idea was very much one of programs that were composed of smaller parts, such that the whole thing was ultimately just the evaluation of a single expression. Note that this definition predates Haskell by a decade or so. It was trying to capture what the designers of APL were going for.