Henry of Ghent’s works out part of his theory of cognition out in response to the question Can a human being know anything without divine illumination? Like Thomas Aquinas, Henry attempts to synthesize the mechanisms of Aristotle’s theory of cognition with the Augustinian doctrine that true knowledge is beyond the natural capacity of human cognition, requiring a gift of divine illumination, however Henry will argue against Thomas that this illumination must be something other than a natural faculty of the soul.
Henry rejects the idea that divine illumination is required for absolutely all knowledge as derogatory to the “worth and perfection of the created intellect” (113). Illumination is needed only for knowledge of the “pure truth”. Henry spends most of the question distinguishing various kinds of intellectual knowledge, the various notions of truth they apprehend and the different cognitive processes that produce them to support this conclusion.
The first distinction (of many) Henry makes in intellectual knowledge is between “simple understanding” and what I call ‘discursive understanding’. To understand simply is “to know of a creature what is true with respect to it” (Pasnau 115). The simple understanding knows “what a thing is” (115) and is concerned with “truth” in the sense that “truth” is convertible with “being”. The intellect knows with simple understanding of a tree that it is a tree because the truth of the tree in the sense of the tree’s being.
The second kind of intellectual knowledge is discursive understanding. To know something discursively is “to know its truth” (115), but the intention of truth invoked here differs from the intention of truth-as-being apprehended in the simple understanding.
The intention of truth known in discursive understanding, “can be apprehended only by apprehending its conformity to its exemplar” (117). This definition of truth gives a hint at how Henry’s account of cognition works.
Although his account of the cognitive processes behind the different kinds of understanding remains somewhat vague, Henry mentions that the simple understanding “entirely follows the senses” and endorses Aristotle’s maxim that “there is no concept in intellect that was not first in the senses” (115). When I see a tree, my eye receives a species from the tree. The species is passed to my common sense and then my imagination forms it into a phantasm. Then my intellect abstracts a mental exemplar (or “universal species”) from the phantasm.
The two different kinds of understanding are not separate faculties; they are different ways the intellect considers the same mental exemplar. The simple understanding cognizes just the mental exemplar itself. The function of the discursive understanding is to make a judgment about the degree of conformity between the exemplar and what it exemplifies, because the discursive understanding knows the truth as conformity to an exemplar.
Henry notices two ways in which the discursive understanding can make this judgment about the correspondence between an exemplar and the exemplified. I call the first way the Comparison Method. I can judge the degree of conformity between an exemplar and what it exemplifies if I am able to directly compare them. Suppose, for example, that I painting a portrait of Alexander the Great from my own imagination. Suppose then that Alexander the Great appears before me. I can now judge the degree of conformity between my painting of Alexander and Alexander by the Comparison Method because I can directly compare them.
It is clear that I cannot judge the adequacy of my mental exemplar by the Comparison Method because I cannot step outside of my own head to compare my mental exemplar of a thing with what it exemplifies directly. As Henry says, we have only “an imaginary apprehension of the thing” (118), meaning an apprehension of a thing through the perceptions formed into a phantasm by the imagination.
Despite this, Henry grants, “the truth of a thing itself can indeed be cognized in a way” (119) by the second way of considering an exemplar, which I call the Conceptual Method. In this method, I examine an exemplar “by forming a mental concept of the thing, conforming to the exemplar” (119). The discursive intellect does this by composing things into genera and dividing them into species. Suppose I see a human being, a horse and a plant. I notice that they are all similar in that they are living things, and then I notice that the horse and the human being move and the tree does not. Then I separate the human being from the horse because the human being is rational and the horse is not. I have now arrived at a concept of a human as a rational, moving, living thing. I can now use this concept to judge the correspondence of my mental exemplar.
Even though Henry says that we can have some purely natural knowledge in this way, he thinks there are three reasons this knowledge is not “an altogether certain and infallible cognition of the truth” (119) and therefore do not count as knowledge of the eternal, unchanging “pure truth”. The first reason is that the mental exemplar is abstracted from a changeable thing and therefore “necessarily has some of the characteristics of a changeable thing” (119). The second reason is that the human soul itself is mutable and the exemplars it receives have an even lower grade of being than the soul, therefore they must be at least as mutable as the soul, hence they cannot actualize the soul with an eternal, immutable truth. The third reason is that the mental exemplar “has a likeness with the false as well as the true” since it is abstracted from the phantasm (120). Henry’s conclusion, and implicit rejection of Thomas Aquinas’s theory of cognition, is this: if someone has certain knowledge, “this is not possible for him by examining an exemplar abstracted from a thing through the sense, no matter how much it is purified and made universal” (121).
The discursive understanding tries to know a thing’s truth by comparing it to an exemplar, but it cannot grasp eternal, unchangeable truths because the mental exemplar that is the result of the natural human cognitive processes is mutable. Therefore, we can have no certain knowledge by means of the mental exemplar. But if we cannot have certain knowledge through the mental exemplar, how do we have it?
Henry responds that “no certain and infallible cognition of the pure truth can be had from anything except by examining the exemplar of uncreated truth and light” (126). In other words certain knowledge must come from the discursive understanding judging a thing’s conformity to its immutable, unchangeable divine exemplar, which can be cognized only by a special gift of grace. This divine exemplar can be examined in the same two ways as the mental exemplar.
A creature can be known through the divine exemplar according to the Comparison Method “since every creature is a kind of image of a divine exemplar” (124). Henry cites a passage from Augustine’s City of God to the effect that angels know creatures by seeing the divine exemplars from which the creatures are made.
This is not the ordinary way divine illumination works, however. Usually we apprehend unchanging truth through the Conceptual Method applied to a divine exemplar. In order for us to have certain knowledge by the Conceptual Method, Henry says that it is “necessary for that uncreated truth to impress itself on our concept and to transform our concept in accord with his character” (127).
What is transformed is not the content of the concept but the way that concept is actualized in the soul. God replaces the mutable mental exemplar with the immutable divine exemplar and the discursive understanding now apprehends the concept in an immutable, certain way. Indeed Henry’s opinion is that we can have no certain knowledge, including knowledge of first principles (131) except by means of divine illumination because “by purely natural means . . . a human being can in no way know the clear truth” (130).
Henry’s doctrine of divine illumination is not philosophically convincing. In the first place the distinction between knowledge and certain knowledge seems questionable. How is it possible that I know something naturally and not be certain about it? If I know Paris is the capital of France, then I am certain that it is. The most cogent response to Henry, however, is Scotus’s argument that we do actually have natural knowledge of first principles because the terms of a self-evident proposition include one another. As soon as the intellect understands the meaning of the terms, it understands the principle as necessary and evident. It certainly does not seem plausible to think that one requires a special act of God’s grace to understand that “All bachelors are unmarried men.” If our understanding were so defective as to need divine illumination to know even this, then our cognitive deficiencies must be dire. Indeed so dire one wonders how Henry thinks they are capable of having anything called ‘natural knowledge’ at all. The only response would be to say that absolutely all human knowing comes from illumination, but Henry has already rejected this approach as derogatory to the worth of the created intellect. Henry of Ghent must either accept skepticism and agree to derogate the intellect or accept natural knowledge of first principles and elevate the intellect slightly.