I’ve been digging around, and found some quotes to back him up. I can’t find any actual cites for them, though…

“GIVE me a progressive, achievement-punishing income tax, or give me death!”

— Patrick Henry

“HAPPINESS, moral duty, and a progressive income tax are inseparably connected.”

— George Washington

“I only regret that I have but a small percentage of my income to give for my country.”

— Nathan Hale

“WHEN in the course of Human Events, it becomes necessary to fund a Welfare State, he that has the most to give, should provide the greatest proportion of his Income.”

“THE Tree of Liberty is a fragile one. Its Roots must occasionally be watered by soaking the Rich.”

— Thomas Jefferson

“THESE are the times that try men’s souls. The wealthy summer soldier and the sunshine patriot will, in this crisis, shrink from the service of their country, by refusing to pay their fair, high share of taxes.”

— Tom Paine

“THE advancement and profusion of an extremely progressive income tax is the only guardian of true liberty. ”

— James Madison

And of course, they all inspired that other great philosopher in the next century, who said “From each according to his ability, to each according to his need.”