Yeah, well, I've heard somewhere that correlation does not equal causation :-)
I agree that causal models are useful -- if only because they make explicit certain relationships which are implicit in plain-vanilla regular models and so trip up people on a regular basis.What I'm not convinced of is that you can't re-express that joint density on the outcomes in a conventional way even if it turns out to look a bit awkward.
Here's how this conversation played out.
Lumifer : "can we not express cause effect relationships via conditioning probabilities?"
me : "No: [example]."
Lumifer : "Ah, but this is silly because of time ordering information."
me : "Time ordering doesn't matter: [slight modification of example]."
Lumifer : "Yeah... causal models are useful, but it's not clear they cannot be expressed via conditioning probabilities."
I guess you can lead a horse to water, but you can't make him drink. I have given you everything, all you have to do is update and move on. Or not, it's up to you.
Yann LeCun, now of Facebook, was interviewed by The Register. It is interesting that his view of AI is apparently that of a prediction tool:
"In some ways you could say intelligence is all about prediction," he explained. "What you can identify in intelligence is it can predict what is going to happen in the world with more accuracy and more time horizon than others."
rather than of a world optimizer. This is not very surprising, given his background in handwriting and image recognition. This "AI as intelligence augmentation" view appears to be prevalent among the AI researchers in general.