I encountered Escher's graphic art for the first time at the home of a beloved uncle who had been collecting this work since 1953. It was with him, also, in the second half of the fifties and in the early sixties that I saw various group exhibitions of Dutch graphic artists, which included Escher. Then, too, in 1954 there was the presentation of Escher's work at the Stedelijk Museum in Amsterdam, an exhibit that came into being on the initiative of an international congress of mathematicians, as the artist had become well known in the world of the sciences.