Laws of nature: Ante res or in rebus?

Abstract

The dilemma which originated in Aristotle's antithesis to Plato and was transformed in the Middle Ages into a debate on universals, revives today in the discussion concerning the character of laws of nature: Do laws exist separately from individual objects (ante res) or should we rather say that they are in things (In rebus,)? My first aim is to show the weaknesses of the Platonist view. To this purpose James R. Brown's theory of laws of nature is discussed as an example of a fruitful revival of Platonism, defending the existence of uninstantiated laws and our capacity to grasp them directly. My claim is that although this theory successfully solves the epistemological problem, it nevertheless fails to meet the challenge of the traditional issue of the χωρισμò?, of the two worlds. This, I argue, can be resolved by an appeal to Aristotle. Thus, my subsequent goal is to advance an alternative solution, built on an analysis of some key concepts of Aristotelean‐Scholastic realism and C. S. Peirce's thought. Particular emphasis is put on the ideas of natures and potentiality, which leads me to the conclusion that laws must be instantiatable, i. e. potentially real as they point to their future instantiations.