[zokier]

> Even without a formal definition, most languages purporting to be OO clearly fail a common sense interpretation of his criteria.

Which should be obvious sign that Kays criteria for OO does not match the common usage of the term, and as such not very useful.

[weatherlight]

I think that the argument is that even the "common usage of the term" means a lot of different things to a lot of different programmers/computer scientists/etc.

[baryphonic]

The more interesting question to me is whether there is still something to the ideas that he originally called "object-oriented" that has possibly been lost. The term itself has been overloaded into oblivion, but message communication, vigilant protection of internal state and late binding all the things might still be a good idea.

IMO "objects := algorithms + data structures" has run its course and hasn't succeeded.