I've seen SPJ's talk. You might notice that in the moment you site, he says that OO and parametric polymorphism are both polymorphism systems. Rust and Haskell

I've seen SPJ's talk. You might notice that in the moment you site, he says that OO and parametric polymorphism are both polymorphism systems. Rust and Haskell are both parametric systems, not OO systems, in SPJ's formulation (and mine). The slide is literally a venn diagram of the two concepts and the abstractions they can encode. What is an example of a language with polymorphism you do not consider to be object oriented? I'm not really interested in being linked to media I've already seen, I'm trying to suss out what you think object oriented means. As far as I can tell, it means "polymorphism," and well - yes I think polymorphism is a great idea, but I don't think its what most people mean when they say "object-oriented." (Also, if Haskell type classes are interfaces, then so are Rust traits. They have the same semantics. But you've already said that Rust traits are traits.)