Jonathan Blow

I have tried to read several books about category theory, but they all appear to dissolve into lists of trivial details before they ever clearly say anything new or powerful. Is category theory really just the idea "hey we can draw equations in 2D instead of 1D",

and then all these books are just listing out what that looks like, or is there really a separate body of ideas about something that isn't already covered everywhere else?

(Not to discount the potential strength of the idea of doing equations in 2D, it's just, everyone seems to be claiming it's more than that, but I don't see it, and I am trying).

I know what you mean. I keep trying to find in set theory anything more than just an alternative notation for predicate logic.

In modern type systems you can define a type like this (example is in Haskell): data X = X (X -> Bool) X is the type of functions that take an X and return a Boolean.