All you have to know about Francis Alÿs is to meet him, which I did at the opening of his retrospective at the Museum of Modern Art last Tuesday evening. At 51, Alÿs, a Belgian who lives in Mexico City, looks like James Taylor, with an impressive aquiline nose, long hair, sweat pants and the skinny body of a 30-year-old long-distance runner. Curators who adore his look, out of Peter Matthiessen by Jackson Browne, physically anathema to a museum office, will tell you that his art is about politics.

But Alÿs is only about himself. This differentiates him from a truly talented artist with a sideways practice about the great unwashed such as Gabriel Orozco. For Alÿs, like the cuckoo robbing another bird's nest, is incapable of originality, stealing creative tropes from just about anyone. All you must do is watch a pathetic video of the tall stud pushing a block of ice down a sunny street in MoMA's sixth floor galleries and think about whom Alÿs ripped off. Could be William Pope.L pushing something with his nose up Broadway 15 years ago. Could be David Hammons kicking a can in a 1997 Whitney biennial video. Could be Hammons selling snowballs at P.S.1 back in 1981.

The curator of this derivative and vain exhibitory tribute to Alÿs, the good-looking mediocrity Klaus Biesenbach, is counting on your lazy mind and inactive artistic memory. Don't let him get away with it. The one piece which I liked in this tedious show depicts Alÿs (who else, it is all about him), walking around a plinth with some sheep, a direct steal from Bunuel's sheep scenes in the church in Exterminating Angel. Klaus Biesenbach can barely remember who he slept with last night, even if it might have been Francis Alÿs (just kidding, Beezer. . .), so how are you supposed to remember a classic surrealist film from 1951?

It gets worse. Perhaps you recall Charlie Ray's brilliant little self-portrait sculpture of himself in a tiny bottle, which, if memory served, graced the 1995 Whitney Biennial? Alÿs the magpie has a cute version of same at MoMA, a tiny woman in a tiny bottle. This isn't even "appropriation" in the respected, if shopworn, tradition of Sturtevant or Richard Pettibone or Sherrie Levine.

It is outright esthetic theft by a good-looking moron who is cunning (the intelligence of the ignorant) and way responsive to the amen choir of his MoMA admirers. If Klaus Biesenbach comes to one more party on the arm of Marina Abramovic, as he did at MoMA Tuesday night, he is gonna end up like Ulay on the Great Wall of China: banished. And he will have earned it by trying to pull of the con job that is Francis Alÿs.

“Francis Alÿs: A Story of Deception,” May 8-Aug. 1, 2011, at the Museum of Modern Art, 11 West 53rd Street, New York, N.Y. 10019.