Quote by Arthur Schopenhauer

All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident.

Comment

This quote is attributed to Schopenhauer but is likely not his (it is translated from his German, in any event, which can lead to questions about what the "real" quote is). In The World as Will and Representation, Schopenhauer wrote (English translation):

To truth only a brief celebration of victory is allowed between the two long periods during which it is condemned as paradoxical, or disparaged as trivial.

See: Science, Pseudoscience, and The Three Stages of Truth

Please suggest source details if you know: book, page, year, online article address (url), correction (different author...), etc.. Thanks.