As I walk through the text of ST II-II.1.1, I will use the comparison chart from last post to track ST I.1.3 as well. I’ll begin with the Respondeo and then return to the objections as I look at the replies.
The first thing to notice is how St. Thomas defines his topic. In the first line of the Respondeo, he says that faith is a habitus, a stable disposition; out of the tremendous range of realities one might call a habitus, he identifies faith as a cognitive habitus, that is, a stable disposition to know something. Then he notes that the way to define a cognitive habitus is to specify what it disposes one to know, that is, the “object.” The rest of the Respondeo is devoted to that project.
So ST II-II.1.1 is a step toward saying precisely what faith is: the highest genus is habitus, the species is cognitive, and the last specific difference is the object. This is a simple unpacking of the comparisons we find in Scripture. In John 9 we find an elaborate comparison of faith with the power of seeing: sight is a power, and specifically a cognitive power, and most specifically the cognitive power of knowing what light reveals. When Jesus speaks a parable, he often concludes by saying, “He who has ears to hear, let him hear!” And in the book of Revelation, Christ says, “He who has ears to hear, let him hear what the Spirit says to the churches!” The ear houses a power, and specifically a cognitive power, and most specifically the power of knowing sound.
St. Thomas goes on to distinguish between the material object and the formal object of a cognitive habitus. Although sight allows me to know trees and cars and birds, the exact thing sight does is allow me to know colored things; if the colors come together one way, I know a tree, and if they come together another way then I know a car, yet seeing a car and seeing a tree are not two ways of knowing but one. And although hearing allows me to know the words “bubble” and “splendid” as well as the timbre of a trumpet, the exact thing hearing does is allow me to know sound; if the sounds are formed one way then I hear the word “bubble,” and if the sounds are formed another way then I hear the trumpet’s tone, yet hearing a word and hearing a trumpet are not two ways of knowing but one.
Given that faith is biblically described as a power of sight while St. Thomas argues that Sacred Doctrine is a science, one would expect him to use sight as an example for faith and geometry as an example for Sacred Doctrine. But to illustrate his point about material and formal objects, he uses geometry as an example for faith and sight as an example for Sacred Doctrine! A strange choice, but it further emphasizes the close connection between the two Summa articles.
In geometry, the way of knowing is through definitions. If I know what a triangle is, and by knowing what a triangle is I come to know the Pythagorean theorem, that is geometry: the definition of a triangle is what St. Thomas calls the media demonstrationis, and it in the light of the definition that I know the conclusion. I could of course come to know the Pythagorean theorem by measuring lots and lots of triangles until I was convinced through experience that they always turn out this particular way, but in that case I would not have the cognitive habitus of geometry. I would know the same material object—the Pythagorean theorem—but the formal object would be different. Similarly one can know a lot of things by reason or experiment that are also revealed in Scripture, but the formal object—the defining difference of the cognitive habitus at work—is different in the two cases.
At this point, St. Thomas gets down to business by specifying exactly what is the formal object of faith. But I’ll take up that up in the next post.
