Abstract

The paper deals with the ontological status of number. The authors are convinced that it is useful to discuss the concept of number within the framework of the Aristotelian division of being into substance and accident. Number can thus be taken as ens in se or ens in alio. Aristotle and Thomas Aquinas believed that number is an accident and their concept is explained in the first part of the paper. In the second part it is shown that the Aristotelian concept is not correct. However, if number is not an accident then it seems that it must be identified with a Platonic entity. In the third part the authors reject this Platonic conclusion that Frege seems to have defended. In the final part, a possible solution is shown: From the logical point of view number is an object but from the ontological point of view it is an entity that depends on linguistic structure.