Introduction On Reconstructing Thomas Aquinas’s Theory of Perception
Oxford philosopher Sir Anthony Kenny once wrote the following about intentionality theory in Aquinas: ‘One of the most elaborate, and also one of the most puzzling, accounts of the harmony between the world and thought is Aquinas’s doctrine of the immaterial intentional existence of forms in the mind.’1 Kenny, and his philosophical predecessor in analytic philosophy studies of Aquinas, Peter Geach, moreover, directed much of their attention to the intricate account of the abstraction process found in Aquinas’s writings, especially the Summa Theologiae, I qq. 79-85. Often these texts in the Summa are seen as the principal canon for Aquinas’s account of mental awareness. For the most part, however, analytic philosophers have paid little attention to the analysis of sensation and perception, and even less attention to Aquinas’s grand exposition and commentary on Aristotle’s De Anima, the Sentencia Libri De Anima with its informed and perspicuous analysis of the internal sense faculty of the vis cogitativa.
The principal goal of this study is to eliminate some of what Kenny called the ‘puzzling’ issues in Aquinas’s philosophy of mind. In particular, this project focuses attention on the epistemological materials propaedeutic to concept formation, for which the process of abstraction with the agent intellect (intellectus agens) is a necessary condition. This study embarks upon an analysis of the process of perception, with special attention paid to the nature, scope, and workings of the internal senses or ‘inner sense’. The analysis articulates the ‘logic’ of these concepts central to Aquinas’s account of sensation and perception. Like Kenny, Geach, and John Haldane, in order to elucidate effectively the perception texts found in the writings of Aquinas, the techniques of contemporary analytic philosophy have been utilized extensively. Accordingly, the method undertaken in this analysis is rooted in how contemporary analytic philosophers undertake their craft. This philosophical interpretation depends substantively on the exceptionally lucid analyses that Haldane has provided over the last two 
decades on the role of analytic philosophy and the development of Aquinas’s theory of intentionality. It may be the case that, in considering issues central to a viable contemporary philosophy of mind, Haldane’s category of ‘Analytical Thomism’ achieves its best success. In discussing Aquinas’s theory of mind, Haldane writes that Aquinas ‘makes claims about the nature of the world, the process of cognition, the semantics of natural language, and the character of truth [...] all of which provide illustrations of both ontological and epistemological realism’. The purpose—what Aquinas might call the telos of this philosophical undertaking—is similar to what Kenny articulated in his The Metaphysics of Mind: ‘an employment of the techniques of linguistic analysis can go hand in hand with a respect for traditional, and indeed ancient, concepts and theses in philosophy.’ This study is a systematic, building-block integrated account of Aquinas’s theory of perception.
In order to direct attention to those philosophers using analytic philosophy as a means to elucidate the philosophical concepts central to the texts of Aquinas, Haldane introduced the term Analytical Thomism’. The analytic method undertaken in this study is in concert with the general direction of Haldane’s suggestions. Moreover, the position advocated in this study is that, contrary to some contemporary Aquinas scholars like Mark Jordan, Aquinas did develop first-rate philosophical work, and furthermore that this keen philosophical analysis is exhibited in his Aristotelian commentaries. Jordan once wrote: ‘In short, no single work was written by Aquinas for the sake of setting forth a philosophy. Aquinas chose not to write philosophy.’  This study rejects Jordan’s theological reductionism, which will be treated in more detail in an appendix to Chapter 1. Readers familiar with my earlier book, Aquinas’s Theory of Natural Law: An Analytic Reconstruction,7 will readily recognize several familiar streams and methods of philosophical analysis. The author’s intention is that this present analytic monograph will be of benefit both to novices coming to the work of Aquinas with little background in medieval philosophy and to academically trained philosophers and also historians of psychology generally interested in medieval theories of mind.
-  Anthony Kenny, ‘Aquinas: Intentionality’, in Ted Honderich (ed.), Philosophy Through Its Past(Harmondsworth: Penguin, 1984), 82.
-  John Haldane, ‘Mind-World Identity Theory and the Anti-Realist Challenge’, in John Haldaneand Crispin Wright (eds), Reality, Representation, and Projection (Oxford: Oxford University Press,1993), 33.
-  Anthony Kenny, The Metaphysics of Mind (Oxford: Oxford University Press, 1989), p. ix.
-  The author is indebted to an anonymous reviewer who offered this analogy about the structure of theargument undertaken in this book.
-  John Haldane, ‘Analytical Thomism: A Prefatory Note’, The Monist 80(4) (1997), 485-6; also Haldane,‘What Future Has Catholic Philosophy?, American Catholic Philosophical Quarterly 71 (annual supplement, Proceedings of 1997 Annual Meeting), 77-90. See also ‘Thomism and the Future of CatholicPhilosophy, ed. Haldane, special issue, New Blackfriars 80(938) (1999).
-  Mark Jordan, ‘Theology and Philosophy, in Norman Kretzmann and Eleonore Stump (eds), TheCambridge Companion to Aquinas (Cambridge: Cambridge University Press, 1993), 233. Ralph McInernyand Leo Elders, among others, reject the Jordan interpretation.
-  Anthony J. Lisska, Aquinas’s Theory of Natural Law: An Analytic Reconstruction (Oxford: ClarendonPress, 1996).