Lloyd E. Sponenburgh wrote:
....

Here's something that says it all... (I quote only approximately, from
memory)

Winston Churchill -- "A man who is not a liberal when he is young has
no heart. A man who is not a conservative when he is old has no
brain!"

Reasonable rendition of meaning but it wasn't a Churchill quote...

Charles Krauthammer in an op-ed piece seems to have repopularized the
misattribution some time ago quoting Churchill as saying, "If you're not
a liberal when you're 20, you have no heart. If you're not a
conservative when you're 40, you have no head."

Churchill was a swashbuckling soldier at 20 and a Conservative member of
Parliament at 25. A couple of years later he switched to the Liberal
Party (which was not liberal in the modern sense) returning to the
Conservatives and leading the opposition up to outbreak of WWII.

The saying appears to have originated with French politician and
historian Francois Guizot (1787-1874) as "Not to be a republican at
twenty is proof of want of heart; to be one at thirty is proof of want
of head."

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