Weiss's first semester at Harvard proved to be a busy one. He volunteered to help Charles Hartshorne in the monumental task of editing the thousands of scattered pages Charles S. Peirce had left behind for publication by Harvard University Press. C. I. Lewis, who was at the time the department chair of philosophy at Harvard, eventually approved Weiss to work alongside Hartshorne for the remainder of the project. The first six volumes of Peirce's work would eventually be published between 1931 and 1935. Weiss was mainly responsible for the second, third, and fourth volumes. Two more volumes, both edited by Arthur Burks, would later appear in the 1950s.