Well, I think "messaging" is an abstract concept. It doesn't have rights, so there was nothing to prove.

Nevertheless, credit matters, because people matter, and do have rights. One of those rights is to have an opinion, including the opinion that messaging is the core of OOP.

> clearly and consistently saying that in the 70s

This is indeed a preposterous and unhealthy standard to expect of anyone, on any topic. It's the kind of thing that two-bit politicians like to dig up on each other, to nobody's edification.