"What concerns me is the proliferation, not just of nonsense and sloppy thinking per se, but of a particular kind of nonsense and sloppy thinking: one that denies the existence of objective realities," he wrote in Lingua Franca.

In an interview, Professor Sokal, who describes himself as "a leftist in the old-fashioned sense," said he worried that the trendy disciplines and obscure jargon could end up hurting the leftist cause. "By losing contact with the real world, you undermine the prospect for progressive social critique," he said.

Norman Levitt, a professor of mathematics at Rutgers University and an author of a book on science and the academic left that first brought the new critique of science to Professor Sokal's attention, yesterday called the hoax "a lot of fun and a source of a certain amount of personal satisfaction."

"I don't want to claim that it proves that all social scientists or all English professors are complete idiots, but it does betray a certain arrogance and a certain out-of-touchness on the part of a certain clique inside academic life," he said.

Professor Sokal, who describes himself as "a leftist and a feminist" who once spent his summers teaching mathematics in Nicaragua, said he became concerned several years ago about what academics in cultural studies were saying about science.

"I didn't know people were using deconstructive literary criticism not only to study Jane Austen but to study quantum mechanics," he said yesterday. Then, he said, he read "Higher Superstition: The Academic Left and its Quarrel With Science" by Professor Levitt and Paul R. Gross.

Professor Sokal said the book, which analyzes the critique of science, prompted him to begin reading work by the critics themselves. "I realized it would be boring to write a detailed refutation of these people," he said. So, he said, he decided to parody them.