Jacques Maritain Center: Thomistic Institute

From Schrödinger's Cat to Thomistic Ontology

by Wolfgang Smith
Abstract of a lecture to be given at the Thomistic Institute,
University of Notre Dame, on July 20, 1998.
The full text is scheduled for publication in The Thomist.


It has often been stated that the discoveries of quantum theory conflict with the philosophical premises underlying the pre-quantum scientific world-view; and yet, as Wolfgang Smith observes, it appears that the most basic philosophic premise behind that world-view has become ingrained in the scientific mentality to the point where it is no longer recognized as a philosophic assumption void of scientific support. Smith identifies this premise as the Cartesian subjectivization of the sensible or so-called secondary qualities, resulting in what Whitehead has termed "bifurcation." Basing himself upon his book The Quantum Enigma (Sugden, 1995), he shows not only that bifurcation can be jettisoned -- without in any way affecting the actual modus operandi of physics -- but that this step, in and by itself, eliminates the quantum paradoxes which have perplexed physicists since 1927, when the celebrated Bohr-Einstein debate first began. As Smith explains, non-bifurcation entails the distinction between two objective ontological domains: the corporeal, which we can perceive, and the physical, which we measure and observe by way of scientific instruments. Every corporeal object X, moreover, is associated with a corresponding physical object SX, from which it derives its quantitative attributes. And yet the two objects are altogether different, one can almost say: worlds apart. In the bifurcationist perspective, however, the two are implicitly identified. The prevailing scientific outlook is thus reductionist: it reduces the corporeal to the physical (the grey stone or red apple to an aggregate of molecules). And therein, according to Smith, lies the fundamental fallacy of the contemporaty world-view, which turns out also to be the source of quantum paradox. In the second part of the paper -- after pointing out that the Aristotelian / lThomistic philosophy is stringently non-bifurcationist -- Smith goes on to show that the results of physics, when interpreted on a non-bifurcationist basis, can be readily integrated into the Thomistic ontology, with the result that one is able to understand the nature and limitations of modern physics from a metaphysical point of view. In this perspective it becomes apparent that the factor distinguishing X from SX can be none other than the so-called substantial form of X, rejected by Galileo and Descartes. In light of these considerations, Smith concludes that the findings of quantum theory actually mandate a return to the pre- Cartesian ontology. The resultant rediscovery of "essence" -- beginning in the inorganic realm -- reverses the reductionism which for so long has dominated Western scientific thought, and opens the door to a deeper understanding of Nature.