ABSTRACT
This chapter aims to state and arrange those general statements in the theory of contraries that constitute a set of rules relating contrariety to the locus of process. It provides an exhaustive analysis of the uses of contraries as presented in the relevant Aristotelian passages and demonstrates the meaning of contrariety as a formal demand. The chapter explores the distinction of prior-posterior, as it fulfils the formal demand of contrariety, to change and development. It shows that the Aristotelian categories display fundamental and pervasive contrarieties, termed 'categorical'. Aristotle correctly points out that to turn process in the abstract into a substance lead to infinite regress. According to Aristotle, truth and falsity are meaningful only in so far as they belong exclusively to propositions, affirmative or negative. He traces the natural movements of up-down to the inherent directional properties of the elements.
