I am reading Gödel's proof book. But there is sentences that i cannot understand.
"One of them "From a fixed set of axioms and a fixed set of typographical rules, one could shunt symbols around and produce new strings of symbols, called “theorems.”. "
"A couple of decades later, Gödel began to doubt this noble vision, and one day, while studying the extremely austere patterns of symbols in these volumes, he had a flash that those patterns were so much like number patterns that he could in fact replace each symbol by a number and reperceive all of Principia Mathematica not as symbol shunting but as number crunching (to borrow a modern term)."
I could not understand what the word "shunt" means. Also "number chrunching". Could you explain these phrases for me?