I honestly beleave it iz better tew know nothing than two know what ain’t so.

[I honestly believe it is better to know nothing than to know what ain’t so.]

Josh Billings (1818-1885) American humorist, aphorist [pseud. of Henry Wheeler Shaw]
Everybody’s Friend, Or; Josh Billing’s Encyclopedia and Proverbial Philosophy of Wit and Humor, “Sollum Thoughts” (1874)
    (Source)

This was Billings signature aphorism, and he used variations on multiple occasions. Variants and evolutions have also been misattributed to Will Rogers, Mark Twain, and Artemus Ward, sometimes from their own paraphrases of Billings. Some variations (usually without specific citations) include:
  • "The trouble with people is not that they don't know but that they know so much that ain't so."
  • "It ain't what you don't know that gets you into trouble. It's what you know for sure that just ain't so."
  • "You’d better not know so much, than know so many things that ain’t so."
In a similar vein, Billings wrote, "Wisdum don't konsist in knowing more that iz new, but in knowing less that iz false. [Wisdom doesn't consist in knowing more that is new, but in knowing less than is false.]" [Source]

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