He taught at the State University of New York at Geneseo from 1972–1978. He got a grant (money to support scholarship) from the Alexander von Humboldt Foundation, so he went to teach math at the Ruprecht Karl University of Heidelberg from 1978–1980. He then taught at Randolph-Macon Women's College in Lynchburg, Virginia from 1980–1982. Next, he tried being as a full-time author for four years. Inspired by an interview with Stephen Wolfram, Rucker became a computer science professor at San José State University in 1986. He retired from SJSU in 2004. He is a mathematician who is also interested in philosophy. He has written books connecting these two areas, for example: "The Fourth Dimension"; "Geometry, Relativity and the Fourth Dimension"; and "Infinity and the Mind". Princeton University Press published new editions of "Infinity and the Mind" in 1995 and in 2005, both with new prefaces; the first edition is cited with fair frequency in academic literature.