The alchemy of good curating amounts to this: Sometimes, placing one work of art near another makes one plus one equal three. Two artworks arranged alchemically leave each intact, transform both, and create a third thing.

Can space break? I mean the space of art galleries. Over the past 100 years, art galleries have gone from looking like Beaux Arts salons to simple storefronts to industrial lofts to the gleaming giant white cubes of Chelsea with their shiny concrete floors.

'Untitled' is a time machine that can transport you to 1992, an edgy moment when the art world was crumbling, money was scarce, and artists like Tiravanija were in the nascent stages of combining Happenings, performance art, John Cage, Joseph Beuys, and the do-it-yourself ethos of punk. Meanwhile, a new art world was coming into being.

Early-twentieth-century abstraction is art's version of Einstein's Theory of Relativity. It's the idea that changed everything everywhere: quickly, decisively, for good.

When I criticize Joseph Beuys or Francis Bacon, nobody calls those opinions anti-male. Putting female artists or their subject matter off-limits is itself sexist and limiting.

All of Koons's best art - the encased vacuum cleaners, the stainless-steel Rabbit (the late-twentieth century's signature work of Simulationist sculpture), the amazing gleaming Balloon Dog, and the cast-iron re-creation of a Civil War mortar exhibited last month at the Armory - has simultaneously flaunted extreme realism, idealism, and fantasy.

In some ways Lawler is a conceptual Diane Arbus. She's a stalker who takes advantage of situations. She pulls back curtains, causing normal things to look freakish and the freakish to turn mundane.