 His work on points sets led Cantor, in 1882, to conceive of the transfinite numbers (see Ferreirós 1999: 267ff). This was a turning point in his research, for from then onward he studied abstract set theory independently of more specific questions having to do with point sets and their topology (until the mid-1880s, these questions had been prominent in his agenda). Subsequently, Cantor focused on the transfinite cardinal and ordinal numbers, and on general order types, independently of the topological properties of \(\mathbf{R}\).