the resulting change: while the first drawings are influenced by Matta and Yves Tanguy, later drawings associated with Motherwell's time with Paalen show more plane graphic cadences and details distinguished from the earlier period. Paalen also introduced Motherwell to André Breton, via a letter. Motherwell's seminal trip to Mexico has been described as a little-known but important factor in the history and aesthetics of abstract expressionism. In 1991, shortly before his death, Motherwell remembered a "conspiracy of silence" regarding Paalen's innovative role in the genesis of abstract expressionism. Upon return from Mexico Motherwell spent time developing his creative principle based on automatism: "What I realized was that Americans potentially could paint like angels but that there was no creative principle around, so that everybody who liked modern art was copying it. Gorky was copying Picasso. Pollock was copying Picasso. De Kooning was copying Picasso. I mean I say this unqualifiedly. I was painting French intimate pictures or whatever. And all we needed was a creative principle, I mean something that would mobilize this capacity to paint in a creative way, and that's what Europe had that we hadn't had; we had always followed in their wake. And I thought of all the possibilities of free association—because I also had a psychoanalytic background and I understood the implications—might be the best chance to really make something entirely new which everybody agreed was the thing to do." Thus, in the early 1940s, Robert Motherwell played a significant role in laying the foundations for the new movement of abstract expressionism (or the New York School): "Matta wanted to start a revolution, a movement, within Surrealism. He asked me to find some other American artists that would help start a new movement. It was then that Baziotes and I went to see Pollock and de Kooning and Hofmann and Kamrowski and Busa and several other people. And if we could come with something. Peggy Guggenheim who liked us said that she would put on a show of this new business. And so I went around explaining the theory of automatism to everybody because the only way that you could have a movement was that it had some common principle. It sort of all began that way." In 1942 Motherwell began to exhibit his work in New York and in 1944 he had his first one-man show at Peggy Guggenheim's "Art of This Century" gallery;