the silly people don't know their own silly business.
 George Bernard Shaw, Pygmalion (1913). copy citation

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Author George Bernard Shaw
Source Pygmalion
Topic business
Date 1913
Language English
Reference
Note
Weblink https://www.gutenberg.org/files/3825/3825-h/3825-h.htm

Context

“they're such fools that they think style comes by nature to people in their position; and so they never learn. There's always something professional about doing a thing superlatively well. HIGGINS. Yes: that's what drives me mad: the silly people don't know their own silly business. [Rising] However, it's over and done with; and now I can go to bed at last without dreading tomorrow. Eliza's beauty becomes murderous. PICKERING. I think I shall turn in too. Still, it's been a great occasion:” source