[delta_p_delta_x]

> I don't agree. Correctness is strictly determined by common usage.

Happy to agree to disagree, especially when there is this much teeth-gnashing about how 'correct' this usage is—just within this thread. My point about 'could of' was even brought up elsewhere.

> Language isn't logically airtight like this.

But it is—or at least, people make it so. In a world where what people say or write is regularly misconstrued/misinterpreted and lands them in jail, or persecuted, or even killed, I believe clarity, accuracy, (factual and syntactic) correctness, and honesty should be something that every writer should strive toward. Someone else brought up contronyms—which I believe ought to be avoided as much as possible because of their potential to cause much confusion even with context ('sanction' is a very powerful example).

This sort of wishy-washy 'it is correct because people understand it' only reminds me of 'alternate facts'. I don't like it and I wish people wouldn't put up with it.