Abstract

This paper is an attempt to understand the method by which Thomas Solly (1816?1875), in his Syllabus of Logic (1839), provided a mathematical formulation of the traditional syllogism. The symbolism, in which analogues of multiplication, addition and subtraction are applied to term variables, is very puzzling at first. This paper provides a clear interpretation for this symbolism and explains why it works. It also addresses other notable features of the symbolism. The paper concludes by comparing the results which Solly obtained by symbolic means with those which he obtained non?symbolically