To these crazy opinions, he adds the crazy conduct of persisting in expressing them
A physician being called on as a witness … in which an attempt was made to prove one of the parties insane, defined madness to consist in conduct or opinions differing from the mass of mankind. Mr. [John Quincy] Adams differs very widely, alas! from the mass of mankind, both in conduct and opinions, if we are to take the House of Representatives as a fair criterion of publick sentiment. He strangely believes that slavery is an evil; that Congress has the constitutional jurisdiction, in all respects, over the District of Columbia; that the right of petition is guarantied to all citizens by federal compact; and that the right of speech justifies him in expressing his sentiments, even on the tabooed question of abolishing involuntary servitude. To these crazy opinions, he adds the crazy conduct of persisting in expressing them; and thus comes doubly within the category of madmen.
~ The Plaindealer (January 21, 1837)