When it comes to citing famous quotations, a good rule of thumb is to attribute any unknown saying to Shakespeare, the Bible, or Winston Churchill. Since Churchill's eloquence and wit is second only to that great proverb maker Anonymous, one is generally on safe ground by claiming him as the original source. Most people won't know any better anyway.
Alas, one particular quote that is often mistakenly attributed to the great Brit is,
Any man who is under 30, and is not a liberal, has no heart; and any man who is over 30, and is not a conservative, has no brains.
While the sentiment is certainly astute, the saying did not originate with Churchill. In fact, that wording is a variation of, "The man who is not a socialist at twenty has no heart, but if he is still a socialist at forty he has no head", which belongs to the former French Prime Minister Aristide Briand, who was himself a recovered socialist.
Briand, however, appears to have cribbed the saying from another French statesman, Francois Guizot (1787-1874), who originally said, "Not to be a republican at twenty is proof of want of heart; to be one at thirty is proof of want of head."
Naturally, the term Republican had a different meaning in Guizot's day and was not synonymous with "wise governance" as it is today. Liberals, however, may prefer Guizot version to all the others.
