[Ads-l] Saying: It ain=?UTF-8?Q?=E2=80=99t_what_you_don=E2=80=99t_know_that_gets_you_into_tr?= =?UTF-8?Q?ouble._It=E2=80=99s_what_you_know_for_sure_that_just_ain=E2=80?= =?UTF-8?Q?=99t_?=so.

[ADSGarson O'Toole]

The saying in the subject line appeared at the beginning of the
Oscar-winning 2015 film “The Big Short”. There are many variants, and
I've been sent several requests to explore the expression's
provenance. Multiple researchers have tackled this topic. The Quote
Investigator website now has an entry:

https://quoteinvestigator.com/2018/11/18/know-trouble/

I concluded that the saying evolved incrementally over time, and it
was not crafted by any of the famous humorists that have received
credit during the decades it has circulated.

[Begin excerpt]
Great thanks to Tom Beeler, Stephen Dorfman, Francis Neelon, Marcos
Tatijewski, Simon Lancaster, Dick Plotz, Lane Greene, and George
Dinwiddie whose inquiries led QI to formulate this question and
perform this exploration. Special thanks to fellow researchers Matt
Seybold, Suzy Platt, Ralph Keyes, Fred R. Shapiro, Nigel Rees, and
Barry Popik who have explored quotations in this family.
[End excerpt]

Feedback welcome
Garson

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