Whitehead (unofficially), Schapiro and Seligmann taught him. Matta accompanied him to Mexico and taught him the technique of psychic automatism, Shahn and Breton argued with him, Frankenthaler married him. Pollock, Krasner, Baziotes, Newman, Rothko and Still were all friends and colleagues; Duchamp, Ernst (like him, intellectuals as well as artists) and David Smith were particularly close. Reinhardt co-authored a book with him, Huelsenbeck delivered a lecture with him. De Kooning and Ozenfant were fellow-tutors at Black Mountain, where Rauschenberg and Twombly were among his students.