“If fifty million people say a foolish thing, it is still a foolish thing.”
Si 50 millions de personnes disent une bêtise, c'est quand même une bêtise.
As quoted in Listening and Speaking : A Guide to Effective Oral Communication https://books.google.com/books?redir_esc=y&hl=es&id=0CcWYwjwyRgC&focus=searchwithinvolume&q=foolish (1954) by Ralph G. Nichols and Thomas R. Lewis, p. 74
Also misattributed to Bertrand Russell, by Laurence J. Peter, in The Peter Prescription : How To Make Things Go Right (1976), but he subsequently attributed to France in Peter's Quotations: Ideas for Our Time (1977).
Derived variant: If forty million people say a foolish thing it does not become a wise one, but the wise man is foolish to give them the lie.
W. Somerset Maugham, A Writer's Notebook (1949), entry for 1901
Variant: If fifty million people say a foolish thing, it is still a foolish thing.