I get what OP is saying, I think..
A great example is where Einstein was once quoted as saying that “There is not the slightest indication that [nuclear energy] will ever be obtainable ", yet that same year Fermi successfully split the uranium atom. By 1939 they understood it was possible to create a chain reaction
I think when you start invoking mathematics though, the question of " Do proofs exist independent of the mind ? " should come into play, iow " Does immutable truth exist independently, or is all truth mutable ? "
The mathematician Paul Erdőse spoke of " The Book ", a visualization of a book in which God had written down the best and most elegant proofs for mathematical theorems. He himself doubted the existence of God, whom he called the "Supreme Fascist" (SF). He accused God of hiding his socks and Hungarian passports, and of keeping the most elegant mathematical proofs to Himself.