MOVING TO FRONT FROM SEPTEMBER 30--UPDATED
Emeritus Professor of Philosophy at Washington University in St. Louis, Professor Gibson was especially well-known for his influential work on the philosophy of Quine. I will add links to memorial notices as they appear.
(Thanks to Gil Harman for the information about Prof. Gibson's passing and Eric Morton for supplying the year of his birth.)
UPDATE: There is now a memorial notice on the Wash U Department's homepage.