Pellegrino University Professor Robert Nozick, a leading scholar in the Philosophy Department, cancelled his spring semester classes because of upcoming surgery for colon cancer.

Nozick, who had been teaching about 40 students in two courses at the undergraduate and graduate level, said he does not expect to return to teaching duties during this academic year.

"I'm optimistic about the surgery and look forward to returning to teaching in the fall," he said.

Nozick, one of only 18 University professors, received the honor last September. Best known for his work on libertarianism, Nozick received tenure at Harvard in 1969, earning recognition for his 1974 book, Anarchy, State, and Utopia.

Undergraduates learned of Nozick's illness in class last Wednesday in by Philosophy Department Chair Christine M. Korsgaard.

"It was a brief announcement and everybody just kind of left in shock," Schrage said.

To allow students time to make other arrangements after Nozick was forced to cancel his class, the Philosophy Department has allowed concentrators extra time to file add/drop petitions.

"They were really helpful to ease the transition," said Daniel K. Schrage '01, who had been taking Nozick's undergraduate class, Philosophy 179, "Social Philosophy."

Schrage and the other 20 students in Nozick's undergraduate class, have the opportunity to join a tutorial on similar topics led by Teaching Fellow Waheed Hussain. But only four students have made the switch so far, Schrage said.