Sidney Morgenbesser was born on September 22, 1921, in New York City and raised in Manhattan's Lower East Side.

[4] It was also at Pennsylvania that, Morgenbesser reports, he held his first teaching job in philosophy and met Hilary Putnam as a student.

[1] Morgenbesser was known particularly for his sharp witticisms and humor which often penetrated to the heart of the philosophical issue at hand, on which account The New York Times Magazine dubbed him the "Sidewalk Socrates.

Hauled off to the precinct lock-up, Morgenbesser only won his freedom after a colleague showed up and explained the Categorical Imperative to the nonplussed boys in blue.Morgenbesser published little and established no school, but was revered for his extraordinary intelligence and moral seriousness.

He was a famously influential teacher; his former students included Jerry Fodor, Raymond Geuss, Alvin Goldman, Daniel M. Hausman, Robert Nozick, Hilary Putnam,[6] Gideon Rosen, Mark Steiner, and Michael Stocker.

In 1967, Morgenbesser signed a letter declaring his intention to refuse to pay taxes in protest against the U.S. war in Vietnam, and urging other people to also take this stand.