Mort Sahl, who delivered biting social commentary in the guise of a stand-up comedian and thus changed the nature of stand-up comedy and social commentary, died Oct. 26 at his home in Mill Valley, CA. He was 94.

An inveterate contrarian and a wide-ranging skeptic, Mr. Sahl was a self-appointed warrior against hypocrisy who cast a jaundiced eye on social trends, gender relations and conventional wisdom. Conformity infuriated him: In one early routine, he declared that Brooks Brothers stores didn’t have mirrors; customers just stood in front of one another to see how they looked. Sanctimony infuriated him: “Liberals are people who do the right thing for the wrong reasons so they can feel good for 10 minutes.”

Mr. Sahl was a shock to the comedy system. Other comedians would pour into his wake, seizing on the awareness that audiences were hungry for challenge. He was their flagbearer.