Is OO design's strength in semantics or encapsulation?

Question

Object-oriented design (OOD) combines data and its methods. This, as far as I can see, achieves two great things: it provides encapsulation (so I don\'t care what data there is,

Answer 1

As a Lisp programmer, whose object system arguably provides neither of these, I say: none of the above.

jwz: "the pseudo-Smalltalk object model loses and that generic functions (suitably constrained by the no-external-overrides rule) win".

I think the desirable attributes which you and others list here (encapsulation, modularity, etc.) are not as inherent in OO as you think. They're often provided alongside Java-style OO, but not purely the consequence of it.