“What silly people wits are!”
Que les gens d'esprit sont bêtes.
Act I, scene i. Reported in Hoyt's New Cyclopedia Of Practical Quotations (1922), p. 883-86.
Le Barbier de Séville (1773)
Original
Que les gens d'esprit sont bêtes.
Le Barbier de Séville (1773)
Help us to complete the source, original and additional information
Pierre Beaumarchais 11
French playwright diplomat and polymath 1732–1799Related quotes

“We all believe silly things. What matters is how silly and how many.”

“You're dealing with a lot of silly people in the marketplace”
On being dispassionate and patient in investments, in an interview in Forbes magazine (1 November 1974); he is contrasting soft-drinks to intoxicating beverages in this example; Buffet eventually became a major investor in Coca-Cola.
Context: You're dealing with a lot of silly people in the marketplace; it's like a great big casino and everyone else is boozing. If you can stick with Pepsi, you should be O. K.

“Silly people say stupid things, clever people do them.”
Alberne Leute sagen Dummheiten. Gescheite Leute machen sie.
Source: Aphorisms (1880/1893), p. 70.

"Silly Love Songs", 1976
Lyrics, Wings
Context: You'd think that people would have had enough of silly love songs
I look around me and I see it isn't so
Some people want to fill the world with silly love songs
And what's wrong with that?
I'd like to know
'Cause here I go again...
I love you.

“What a lonely and silly thing it is to be an Armenian writer in America.”
"The Armenian Writers : A Short Story" (1954)

"Live" with Thomas Sowell https://www.aei.org/publication/live-thomas-sowell/, The American Enterprise, September 2004.
2000s

“Everything people did seemed so silly, because they only died in the end.”
Source: The Bell Jar

“Silly what's his name, the Shrek, whoever he was on the television this morning?”
Referring to Howard Government Minister Joe Hockey, Lateline interview, June 7 2007.