are we sure this quote is from Shaw?

Usually attributed to Churchill, it's supposedly by François Guizot (1787-1874): "Not to be a republican at twenty is proof of want of heart; to be one at thirty is proof of want of head." Guizot was a minister under Louis Philippe, the citizen king of France. It seems to have been revived in the 20th century in its modern form by Clemenceau.


Ceci n'est pas un seing.