This question is about Paul Benacerraf, who worked on the philosophy of mathematics, and wrote the 1965 essay What numbers could not be (see: Benacerraf's identification problem). He was at Princeton in the 1960s up to the end of the '00s, and presumably appears in at least one of the following two photos from 1968 and 1979 respectively.
My question is, can we identify Benacceraf in either of these photos? My purpose is to use a picture of him roughly contemporaneous with the essay in a seminar for undergraduate students.