It’s a quote from Winston Churchill. I didn’t make it up.
I know O’l Winnie was wrong about that one.
The quote: "If you're not a liberal at 20, you have no heart. If you're not a conservative at 30, you have no brain."
The quote is often attributed to Churchill, but he did not say it:
https://winstonchurchill.org/resources/quotes/quotes-falsely-attributed/
However, many people did say something similar: