"Knox, you are the only one around with aesthetics!"
- Alex Katz
"You are my mentor. For years, I always asked, what would Knox think of my painting?"
- Bob Rauschenberg
"I was present when Knox Martin changed the life of a major artist by diagramming the basic structure of a Frans Hals. That artist was Al Held."
- Ron Gorchov
"Knox, you are the spirit of art!"
- Peter Golfinopoulos
"Knox, your work has a snooty look about it, I haven't seen outside of Matisse."
- Willem de Kooning
"There are many sexually overt works in this exhibit but the painting with no recognizable image, (Caraja) by Knox Martin; its head and shoulders more sexy than anything there!"
- Elaine de Kooning (Excerpt from a writing on a Whitney Museum exhibition)
"Anyone interested in drawing should see this exhibition of drawings by Knox Martin; he is his own man!"
- Hilton Kramer (Excerpt from the New York Times)
"This is the greatest drawing I have ever seen!"
- Stanley Boxer (Signaling out a drawing by Knox Martin, opening night at an Ingber Galley exhibition)
"Charlie Egan has taken you on. You have no idea how jealous everyone is that you have been taken on by Charlie."
- Aristedemos Kaldis (Knox Martin opening, 10th Anniversary Exhibition Charles Egan Gallery 1954 - advertised in the New York Times)
After Knox had given a talk on children's art (Olivia's paintings and drawings) age 6, on paper and blackboard, to Cy Twombly, Bob and Susan Rauchenberg -- Cy jumped up and said, "That's what I am going to do for the rest of my life!" He did.
- Cy Twombly
"Knox, your paintings are first rate!"
- Alfred Leslie (Reported by Charlie Egan)
"Knox Martin was the first artist whose work I thought about critically and analytically."
- Arthur C. Danto