St. Thomas famously wrote the Summa Theologiae for beginners (ST Prologue). He did not write it to supplant the Sentence-Commentary's role in the training of Masters. Nor was it ever likely that he envisaged scholars writing commentaries about it. Yet from the 15th century onwards precisely that happened, and this collection of essays edited by Lidia Lanza and Marco Toste explores that tradition.
The first four chapters deal with the commentary tradition's history. Hence in chapter one the editors provide a helpful summary of its historical and geographical development whilst in chapter two Monica Brînzei and Chris Schabel examine the period prior to its emergence. In chapter three Ueli Zahnd examines the earliest commentary literature whilst in chapter four Matthew Gaetano discusses the commentary tradition at the University of Padua whose context was renaissance humanism. None of these chapters determine what precisely accounted for the emergence of a distinct Summa Theologiae-commentary tradition two centuries after Aquinas's death. Zahnd suggests the Reformation (p.151), but one of the implications of Gaetano's chapter is that this could not have been the only cause. One is left to wonder what contribution Trent might have made.
The more speculative part of the collection begins with two chapters on the existence of God. In chapter five Igor Agostini examines the work of Giovanni Domenico Montagnolo and Sante Mariale, two independent minded Italian Dominicans, who defended a priori demonstrations of the existence of God. Typically Dominicans denied such demonstrations could prove the existence of God because they required a prior cause (hence a priori) on account of which (propter quid) the phenomenon to be demonstrated depended. In the case of God, two problems arose. First, since God was uncaused there could be no prior cause in the order of being from which the demonstration could proceed. Second, God's essence was not sufficiently knowable to act as the middle term of a demonstration.
Agostini describes how Montagnolo and Mariale sought to avoid these concerns. Yet despite their skilful dialectical precisions, it is hard to avoid the conclusion they failed. The problem lay with the premises of demonstrative syllogisms whose characteristics, Aristotle argued, included immediacy (amesos) (Post Analyt. 71b 20). Such immediacy, John of St Thomas observed, could be either formal or virtual and if virtual, then resolvable into formally immediate premises (CPT ed. Reiser p.774). Neither option recommended an a priori demonstration of God's existence. If the former were true, then such a demonstration would be indistinguishable from Anselm's ontological argument; one understands that God's essence is God's existence and thus one infers that God exists. If the latter were true, then there would be premises into which claims about God's essence could be resolved and thus realities signified by those premises which were prior to God. Either way one faced significant difficulties, and it is not surprising the approach was not widely favoured.
In chapter six Mauro Mantovani examines a problem arising from the nominal definitions of God employed in the five ways. What makes God the first cause whose existence is demonstrated by each way? Might not something else, an angel perhaps, also fit those definitions? Further, if God turns out to be the relevant first cause, and the subject of theology is God, then how can theology demonstrate the existence of its own subject? Cajetan had famously approached the problem by arguing that the five ways only proved the existence of God per accidens because no science could demonstrate the existence of its own subject and it was not clear that the characteristics attributed to God in virtue of the five ways were proper to God. Unsurprisingly that solution provoked controversy and Mantovani tracks the various 16th Century Iberian Dominican and Jesuit responses throughout the chapter. One senses that more attention should have been paid to the context of the five ways. Antoninus Finili OP, writing in Dominican Studies in 1951, had observed that this context was entirely theological. As such the nominal definitions were proper to God in virtue of the theologian's faith. Nor was any attempt being made to demonstrate the existence of theology's subject. Rather, with the existence of the subject taken as given, the theologian sought to show how God's existence formed part of the rationally demonstrable deposit of the faith, given assent to the relevant nominal definition.
In chapter seven William Duba examines the differences between Aquinas's account of the light of glory and those of Molina, Vázquez, and Suárez, as well as their different interpretations of the Council of Vienne's relevant teaching. According to Aquinas the light of glory was a disposition of created grace which elevated the intellect so that it could be united with the divine essence. Each of the Jesuits, however, departed from that view to some degree. Molina, who glossed Vienne as recommending and encouraging Aquinas's view, nevertheless held that the light of glory, construed as a disposition, was not necessary. In principle God could have employed an impressed species as the light of glory. Vázquez went even further and insisted that Vienne affirmed the light of glory but deliberately left its character undetermined, which he subsequently identified as an impressed species. Suárez read Vienne as affirming the necessity of the light of glory which he then specified as a co-efficient force.
These Jesuit commentators were at odds with Aquinas on at least three points. First, that a species could adequately represent the divine essence, when clearly for Aquinas it could not. Second, that a species could elevate the intellect. On Aquinas's view impressed species only actualised the intellect. They disposed the intellect to cognition of a given thing which, crucially, was always proportionate to that intellect's power. Species did not elevate the intellect and thus could not take the place of the light of glory; they simply were not the right sort of thing. Third, for Aquinas the elevation of the intellect by the light of glory was logically prior to and necessary for the beati being able ‘to see’ the divine essence. By analogy, no amount of forcing oneself to look at the sun will help one see it clearly. On the contrary, doing so will only damage one's eyes. So too, without the elevation of the intellect by the light of glory, one will not be able to ‘see’ the divine essence whatever else God might do.
In chapter eight Helen Hattab discusses Molina's, Vázquez's, and Fasolo's accounts of the creation of prime matter. Aquinas, as is well known, held that creation was proper to subsisting beings or substances and that prime matter was pure potential. As such prime matter was not properly created and only existed in virtue of the existence of substances. Molina agreed that prime matter was pure potential and not properly created but distinguished two further senses of ‘creation’ – non-proper senses – one of which allowed him to speak of prime matter as created. Vázquez, on the other hand, employed one sense of creation but two senses of ‘subsist’: that whose nature was not to depend on a subject regardless of whether in fact it did and that which existed but did not depend upon a subject. The former sense allowed Vázquez to say that prime matter was both created and subsistent. At the same time, and it would seem independently of his semantic claims, Vázquez also attributed a proper being to prime matter. Fasolo took things still further and insisted that prime mater was created and enjoyed proper subsistence even if it was never found esse in rerum natura without form.
To understand the way in which these Jesuit commentators diverged from Aquinas's treatment it is important to distinguish a metaphysical doctrine of creation from its logical corollaries: the former treats of things which are created, the latter of how ‘creation’ and related terms are predicated. An analogical extension of terms such as ‘creation’, ‘subsistence’, and their cognates, as arguably Molina and Vázquez engage in, is not ipso facto inconsistent with Aquinas's view and may even complement it, e.g. ‘created’ grace. Where the divergence does lead to inconsistency is when in the metaphysical order a proper being is attributed to prime matter.
In chapter nine Daniel Novotný and Tomáŝ Machula discuss Cajetan's, Báñez's, and Gregory of Valencia's accounts of angelic location. In the Summa Aquinas had argued it was appropriate for an angel to be in a place through virtual quantity (quantitas virtualis) (ST 1a Q52 art 1). Such means of location followed upon the application of an angel's power to a given place and differed from that proper to bodies. However, in order to be consistent with Aquinas's Sentence-Commentary claim that angels did not have to be in a place (I Sent d37, q3, art. 1 ad 4), the Summa claim had to be taken as contingent. That is, if an angel were in a place, it would be so as a result of the application of its power. Yet no angel was obliged to exert its power on a place; angels could exist without a place.
This gave rise to a number of difficulties, however. For instance, if an angel existed without a place, was it nowhere? Further, if an angel existed in a place in virtue of the application of its power, did that mean its substance was not in a place? Both these claims had been rejected in the condemnation of 1277, so Aquinas's successors had to show not only that his view and their developments of that view were coherent but also that their accounts differed from the proscribed positions.
Cajetan's response was subtle and complex. He explained the location of angels by a relation of presence between an angel and a place. That relation of presence was fleshed out as an ordering presence (a sailor on a ship able to act) and an operational presence (the same sailor acting on the ship). Ordering presence was used to explain the relation of inactive angels to places and was called incomplete presence. Operational presence was used to explain the relation of active angels to places and was called complete presence. In both cases angels were present as substances rather than through their substance. Further controversy arose from the foundation of the relation of presence. It was not clear whether Cajetan identified it as the application of power or a transient action and so Báñez went on to distinguish three candidates for the role. A more sympathetic reading of Cajetan might have avoided this, but with the die cast Gregory of Valencia, a Jesuit, went still further and proposed multiple kinds of angelic location.
Limitations of space prevents discussion of the chapters on moral issues (10-13) but overall the collection is impressive and all the contributions are of a high standard. It suffers from two principal defects, however. First, the historical section would have benefitted greatly from a chapter on the influence of Trent. Second, the speculative chapters present the material purely historically. There is little sense that the contributors view these discussions as philosophically or theologically interesting in their own right.