During a pause between songs at the Theatre of Living Arts on Saturday night, Gang of Four guitarist Andy Gill invited the audience to join him after the show for a discussion of the U.S. Constitution. He was kidding, but if any band's performance might dovetail with a study group, it would be the one.

Formed in Leeds, England, in the late 1970s, Gang of Four was one of a handful of punk bands as articulate as it was angry. Instead of singing love songs, the band sang songs about love songs, or, more frequently, about the ravages of late 20th-century capitalism and the dehumanizing nature of work.

Steeped in Marxist aesthetics, the band's music was dialectic, pitting opposites against each other. At the TLA, the dance-floor rhythms of drum and bass weathered assaults from the razor-sharp, arrhythmic slash of Gill's guitar, and singer Jon King nimbly rode the shock waves, his body bucking and twisting.

Gang of Four has broken up and reformed twice, always with King and Gill. But it has taken seven years for the most recent reunion to produce an album, Content, which the duo helped finance by selling everything from signed CDs to vials of their own blood.

Gang of Four's most complicated achievement has been to mount a critique of consumer culture while embedding its music within it. The contradictions inherent in playing a song called "To Hell With Poverty," whose chorus urges "Let's get drunk on cheap wine" to a crowd that paid the equivalent of half a dozen bottles of Ripple for each ticket could not have escaped the band.

Although the songs from Content do not measure up to Gang of Four's best work, they fit easily between older numbers, extending their legacy without expanding it. The indie-rock vogue for aping Gill's guitar sound has come and gone, but the thrill of his barbed assault is as keen as ever.

King quickly worked himself into a sweat, crouching shirtless in a corner of the stage when Gill took a rare lead vocal. The crowd was hot as well; an abortive attempt at starting a mosh pit nearly led to a fistfight early in the set. But a few songs later, the combatants were dancing several feet apart, letting the music do their fighting for them.