AI has a long history of ignoring its philosophical critics, thinking that technical skill trumps their tired and ancient abstractions. This is sometimes valid, but two of the classic philosophical critics Hubert Dreyfus and John Searle actually were worth paying attention to, it turns out. The same might be true of Hart, although I can't quite see it.
Man I would have liked to see a dialog between Minsky and Varela. I remember an episode in grad school where I tried to convince Marvin that all this embodiment stuff was worthwhile and a good fit with his own approach, but I didn't get anywhere. Probably the decades-old enmity between MIT-AI and Hubert Dreyfus had something to do with that.