St. Thomas famously maintained that words could only be used of God and creatures analogically (ST 1a Q13 art. 5). However, despite insisting on the theological utility of analogical language, St. Thomas never offered a general account of analogy, preferring instead to limit his remarks to the application of analogy to talk about God. Traditionally the Dominican Thomistic commentator Cajetan is credited with filling this lacuna in his short work De nominum analogia. There, it was suggested, Cajetan systematized St. Thomas’ remarks on analogy, distinguished three kinds of analogy (inequality, attribution and proportionality) and privileged one of those kinds – analogy of proportionality, on account of metaphysical considerations. As a result, assessments of De nominum analogia have tended to focus on Cajetan's fidelity to St Thomas in the pursuit of that agenda and then criticised or praised Cajetan accordingly. In this book, Joshua Hochschild challenges the traditional account of De nominum analogia and argues that Cajetan is trying to explain to his contemporaries how analogical language can be used in valid reasoning.
The book is divided into two sections. The first section (chapters 1–4) defends the claim that the traditional view of De nominum analogia is wrong and Hochschild's interpretation is correct. Chapter one argues that there are too many anomalies for the traditional view of De nominum analogia to be upheld. Chapter two argues that in De nominum analogia Cajetan is engaged in a semantical or logical project which is concerned with demonstrating how analogical language can be used in valid reasoning. Chapter three argues that the account of analogy which Hochschild attributes to Cajetan pays enough attention to linguistic context to overcome Ashworth's and Gilson's objections to standard Aristotelian semantic analysis of analogy. Chapter four considers several semantic principles that Aquinas cites in the course of his remarks on analogy and argues that none of those principles is sufficient for solving the problem which Hochschild maintains that Cajetan wants to solve.
The second section of the book (chapters 5–9) expounds Hochschild's interpretation of De nominum analogia. Chapter five articulates Cajetan's general semantic principles. Chapter six discusses why Cajetan denied that the analogies of inequality or attribution were genuine kinds of analogy. Chapter seven discusses the role that ‘proportional unity’ or ‘similarity’ played in Cajetan's defence of analogy of proportionality. Chapter eight discusses the extent to which a common concept can be abstracted from things named analogically. Chapter nine uses the concept of ‘proportional similarity’ to argue that analogical language can be used in valid reasoning.
Hochschild does three things very well in this book. Firstly, he sets the dispute about Cajetan's intention in De nominum analogia in its scholarly context. Secondly, Hochschild succeeds in showing that in De nominum analogia Cajetan intended to do more than just explain or systematize St. Thomas's views on analogy. Thirdly, Hochschild provides a useful summary of the main ideas in De nominum analogia.
Hochschild is less convincing when it comes to the details of the interpretation of De nominum analogia that he advocates. For example, Hochschild suggests ‘… analogical signification is semantically possible, because analogical relationships are metaphysically real’. (p. 138) Earlier on however, Hochschild had criticised the idea that Cajetan used metaphysical considerations to distinguish kinds of analogy and thereby privilege analogy of proportionality. (pp. 23–26) The different claims do not appear to be compatible and hence they challenge Hochschild's contention that Cajetan was engaged in a purely semantic project. Secondly, if the point of Cajetan's project was to demonstrate how analogical language could be used in valid reasoning, why did Cajetan wait until the penultimate chapter of De nominum analogia to discuss the principal objection to that project – how analogical language could avoid the fallacy of equivocation? Chapters 3–9 of De nominum analogia can support interpretations that are different from Hochschild's explanation for Cajetan's delay and hence those chapters do not offer strong support for Hochschild's explanation. Thirdly, the discussion of Ashworth's and Gilson's objections to standard Aristotelian analyses of analogy is ill judged. Ashworth's and Gilson's objections challenge the utility of standard Aristotelian analyses of analogy not the attribution of such analyses to particular authors. Consequently, Hochschild does not need to examine such objections unless he also wants to argue that Cajetan succeeded in explaining how analogical language can be used in valid reasoning. But if Hochschild does want to make that case, then more needs to be done to explain the concepts of ‘proportional similarity,’‘isomorphism’ and ‘imperfect concepts’ for the argument to be persuasive.
Finally, how far is all this from St. Thomas? Cajetan was a Thomist after all, Thomists do use St. Thomas's work and a case can be made that St. Thomas defended analogy of proportionality in De veritate 2, 11.
