• One of the central developments of 19th century mathematics involved a dramatic increase in the standards of mathematical rigor. This was for a variety of reasons, but the short version is that there was a need to be stricter about the standards of proof, because certain familiar modes of reasoning had started to lead people astray, or at least threatened to do so.

    Richard F. Heck: One of the central developments of 19th century mathematics involved a dramatic increase in the standards of mathematical rigor. This was for a variety of reasons, but the short version is that there was a need to be stricter about the standards of proof, because certain familiar modes of reasoning had started to lead people astray, or at least threatened to do so.
    Source: www.3ammagazine.com