  Zabarella also developed a theory of the middle (or mixed) sciences that, contrary to the prevailing view, afforded sciences such as astronomy and optics full demonstrative status despite their borrowing principles from pure mathematics. Nevertheless, Zabarella’s approach to the study of nature remained causal and qualitative in the traditional Aristotelian vein rather than mathematical. Therefore he gave little attention to the possible uses of mathematics as a tool for understanding the physical world (Laird 1983, Ch. 8).