Paul Kay (born 1934 in New York) is an emeritus professor of linguistics at the University of California, Berkeley, United States.
He is best known for his work with anthropologist Brent Berlin on colour: Basic Color Terms: Their Universality and Evolution (1969) ISBN 1-57586-162-3.
He is currently working on an extension of Construction Grammar called Sign-Based Construction Grammar, authoring a book on this topic with Charles J. Fillmore, Ivan Sag and Laura Michaelis.
Since 2005 Kay has returned to experimental testing of the Sapir-Whorf hypothesis and his findings show that taking into account brain lateralization allows another perspective on the debate.
More specifically he proposed that "Whorf hypothesis is supported in the right visual field but not the left".