I've been researching your point since I read your comment, but I haven't been able to learn if he actually disliked functional languages.

Personally, I prefer Haskell or some functional Python at times, since that solves certain problems well. But, we have a lot more computing resources than existed in the past. I guess it could be possible that he enjoyed the functional paradigm, but pragmatically created a procedural language, given the hardware constraints.

I thought he was talking about Mathematics.

It's a functional language.

Always has been.

From that standpoint, C is a functional language. Functions are first class citizens in C. I doubt that is what he was discussing.