From a reader:
Dear Jonah,
One could make a strong case that the three most intelligent presidents were (1) Madison, the genius behind “The Federalist”, without doubt intellectually superior to the clever tinkerer Jefferson; (2) John Quincy Adams, a child prodigy and adult polymath; and (3) Hoover, who succeeded brilliantly at everything he tried in his pre-presidential career. All, of course, were failures as president.
Best regards,
Jim Christiansen