In my previous post, I referenced a book review [pdf] of a Bergmann's Theory of Relativity I bought as a teenager not because I understood it, but because I aspired to understand it. I thought I'd call out a couple of quotes. First, one that is partially a response to Blackford's claim that classical mechanics didn't have logical contradictions:
Someone may look for a book on Relativity Theory which states clearly and axiomatically the assumptions of this theory and develops deductively the conclusions from these assumptions. This is not what Bergmann's book tries to do. What it tries to do, and does excellently, is to show how we were compelled to adopt these assumptions, how the structure of Relativity grew from logical contradictions in the classical theory, how their removal leads naturally and simply to the Theory of Relativity. The author presents not the painful historical process, not how Relativity was discovered, but how it should have been discovered if we had known the simple and straight road of logic leading to its formulation. Even in Relativity Theory, created almost by the genius of one man, this difference between the historically and logically reconstructed process is remarkable; it is the difference between the broad highway and the pioneer's narrow pathway.
This also is an example of noting the difference between what I call "Wikipedia science" (where everything is worked out) and "real science" (which is messier). It's that difference between the broad highway and the narrow pathway.
Also, I remembered that it was the first place I'd heard about Kaluza-Klein theory:
The third part (pp. 245-279) is of much more special character and deals with the unification of the gravitational and electromagnetic field. Here we find an exposition of Weyl's and Kaluza's theories and of their generalizations on which the author collaborated with Einstein. This part will rather interest specialists than students.
The review is from July of 1943. When it came up in string theory and the discussion of extra dimensions in the late 1990s, I thought back to the book and its strange (at the time) final chapters.
You never know where theory will lead, or end up becoming useful or relevant again.