Probably only an art-worlder like me could assign deeper meaning to something as simple and silly as Tebowing. But, to us, anytime people repeat a stance or a little dance, alone or together, we see that it can mean something. Imagistic and unspoken language is our thing.

As I went through 'This Progress,' one of two performance pieces by Tino Sehgal that transform Frank Lloyd Wright's emptied-out spiral into a dreamy Socratic-purgatorial journey, the museum literally fell away. I was suspended in some weird nonspace.

It's art that pushes against psychological and social expectations, that tries to transform decay into something generative, that is replicative in a baroque way, that isn't about progress, and wants to - as Walt Whitman put it - 'contain multitudes.'

Living and working for four decades in a Bologna apartment and studio he shared with his unwed sisters, Morandi painted little but bottles, boxes, jars, and vases. Yet like that of Chardin and the underappreciated William Nicholson, Morandi's work seems to slow down time and show you things you've never seen before.

Koons's work has always stood apart for its one-at-a-time perfection, epic theatricality, a corrupted, almost sick drive for purification, and an obsession with traditional artistic values.

Think of an abstract painting as very, very low relief - a thing, not a picture.

Robert Rauschenberg was not a giant of American art; he was the giant. No American created so many aesthetic openings for so many artists.