Paul Cohen

Born in 1934 in Long Branch, New Jersey, into a Polish-Jewish immigrant family, Cohen grew up in New York. He earned a PhD in analysis at the University of Chicago under Antoni Zygmund, then worked at MIT and the IAS before joining Stanford in 1961. After turning intensively to set theory in 1962, he invented forcing and established the relative consistency of adjoining ¬CH in 1963. Combined with Gödel’s 1940 CH direction, this established independence of the continuum hypothesis from ZFC. The forcing work earned Cohen a Fields Medal in 1966; he remained at Stanford and died in 2007.

This is a thought experiment about influence, not a verified historical fact.

Without forcing, the construction of ¬CH models complementing Gödel’s CH direction—and thus the completed independence result—would likely have arrived later. From the 1960s onward Solovay, Lévy, and many other set theorists developed forcing for a wide range of model constructions and independence questions involving measurability, weakenings or failures of choice, and the Suslin hypothesis. Cohen’s move from analysis into set theory became a prominent example of crossing disciplinary boundaries.