"AI has no theoretical underpinning" Very good - that is the hole in what I said about AI. I have always thought of AI as a part of computer science but of course it is possible to think of it as separate. In that case it is underpinned by computer science and (?). Neuroscience if you are trying to duplicate human intelligence (or even ant intelligence) in a non-biological system. But neuroscience is not sufficiently developed to underpin anything. I don't know how far Information Theory has progressed but I suspect it is not up to the job at present.