Introduction

Some years ago, Jonathan Barnes introduced a discussion of ‘Aristotle's theory of demonstration’ with the following statement:

Barnes argued against three traditional attempts at reconciliation, and provided a radical diagnosis for these failures: the scientific treatises report the tentative explorations of ongoing inquiries, while the Posterior Analytics provides a theory of how to present already acquired knowledge. On this view, the attempt to shed light on the APo. theory of scientific knowledge by a close study of the biological treatises is doomed at the outset.

Barnes has himself drawn back from this conclusion (1981), reviving Friedrich Solmsen's thesis that there is a presyllogistic theory of demonstrative science within APo., which may after all be reflected in the scientific treatises. Both of these papers presuppose that unless one first accounts for the absence, in Aristotle's zoological explanations, of an overtly syllogistic form, one cannot proceed any further in exploring the relationship between his theory of science and his scientific practice.