Minimalists were out to purge what Judd called their "specific objects" from any stray associations with human participation and use, but Serra was moving in a different direction. Like the rubber tent, One Ton Prop (House of Cards) suggests a makeshift shelter. It combines immense weight—four 4-foot-square lead plates 1 inch thick—and delicate balance. In his book Pictures of Nothing: Abstract Art Since Pollock, Kirk Varnedoe suggests that Serra is invoking Chardin's beguiling painting of a boy making a precarious house of cards. But Serra, who is well-read in philosophy, may also be alluding to a well-known passage in the Philosophical Investigations, when Wittgenstein wonders whether his subversive undercutting of "great and important" metaphysical questions is "leaving behind only bits of stone and rubble." Wittgenstein concludes: "What we are destroying is nothing but houses of cards and we are clearing up the ground of language on which they stand." Serra may be saying that the minimal means of a sculpture like One Ton Prop clears the ground for more interesting forms. The surface of Serra's lead sheets is a beautiful gray-blue mottled with green highlights, like Monet's late water lilies.