Gerald Sacks

From Wikipedia, the free encyclopedia

Gerald Sacks is a logician who holds a joint appointment at Harvard University as a Professor of Mathematical Logic and the Massachusetts Institute of Technology as a Professor Emeritus. His most important contributions have been in recursion theory. Named after him is Sacks forcing, a forcing notion based on perfect sets.

Sacks earned his Ph.D. in 1961 from Cornell University under the direction of J. Barkley Rosser, with a dissertation entitled On Suborderings of Degrees of Recursive Insolvability. Among his notable students are Harvey Friedman, Leo Harrington, Richard Shore, and Theodore Slaman. A distinctive characteristic of his logic classes was that in the middle of each class, a previously selected student would have to get up and tell a joke. The joke had to be short, funny, and inoffensive to receive credit.