In the course of the evolution of his views, Kotarbiński changed both the formulation of the doctrine of reism and its name. At one stage he called it concretism, and at another pansomatism. The first of these alternative terms, treated by him as a synonym of the original term "reism", is related to the recognition of objects from the category subject to reistic reduction as abstract objects, and the second to the choice of the materialistic version of reism, after realizing the possibility of its dualistic or spiritualistic version. It is shown that actually the first of them is not a synonym, but rather reism is a special case of concretism, and pansomatism is a special case of materialistic reism. Moreover, reism as such is not a radical version of nominalism, contrary to the opinion of many authors, including Kotarbiński himself.