Back in the 1970s, Conceptual Art was notorious for its high seriousness. Conceptualism called for a temperament that was ascetic, politically portentous and relentlessly critical of received notions of art. "Art as Idea as Idea," as Joseph Kosuth dubbed it, was all about ideology, epistemology and linguistics.

And then there was Don Celender, the creator of Artball Trading Cards (1971), which presented artists like Pablo Picasso, Jasper Johns and Larry Rivers as baseball players, each assigned a position and identified on the back by a "hit" artwork.