18 January 2016

Prolegomena to the Construction of an Argument Analogous to St. Thomas's Fourth Way

A reader wrote to me recently asking for a continuation of the dialogue given in this post.  While I never continued that dialogue, it was an expression of an internal dialogue I've been having with myself for the past few months about the natural knowability of the real order of perfection in things.  The topic emerged in the course of my work revising my commentary on the treatise De Deo Uno, questions 1-26 of St. Thomas's Summa Theologiae.  Below I present an excerpt from a draft of my commentary on Summa Theologiae Ia q. 2 a. 3, in which I lay the groundwork for an argument constructed along the lines of St. Thomas's "Fourth Way".  Allow me to emphasize that this is a draft and the line of thought is imperfect, though I think the rudiments are somewhat compelling.


One of the most ordinary things a person can do is make a judgment of something’s quality or value. “These oranges are bad.” “That movie was good.” “The traffic lights are poorly timed.” “These mosquitos are terrible.” In one way, these judgments of value can be thought of as mere expressions of our dispositions toward things. Thus, saying something is “good” or “bad” is just another way of saying that I like or dislike that thing. People make value judgments in this way all the time.

Suppose however, that you are a gardener, and the spring tulips are just coming up. You compare them all, find one that is most excellent, and cut it. Now, you have a perfect tulip. But what makes the tulip perfect? Is the tulip really perfect, or is it only perfect by virtue of the fact that you like it?

There are two ways of answering this question: subjectively and objectively. On one hand, suppose you are growing tulips in order to use their flowers in an arrangement. You have a set of preferences that determine whether you judge a tulip to be more or less perfect, and those preferences may be based on your tastes and needs, rather than something intrinsic about the tulip plants themselves. For example, maybe you want only yellow tulips, and not red ones, or tulips whose stems are a certain length. Granted, your preferences are limited by what is naturally possible for a tulip, but they are imposed upon the tulip by you.

On the other hand, we can talk about the intrinsic perfection of a tulip plant. What does that mean? Well, we observe among all the tulip plants in your garden a commonality of makeup, structure, or form. All of them behave in the same way, develop along the same lines, have the same general features, and so on. It is this common form which makes each tulip a tulip, and which defines the species to which they all belong. Granted, in each individual plant, what is common to all the tulips is instantiated differently, based on the particular variations in material circumstances, nourishment, and so on. But we have no real difficulty in recognizing the sameness of makeup and identity between all the members of the species.

Once we recognize the sameness or specific form which characterizes all of these plants, we can start to look at each individual plant, not just in terms of its own chance features, but in relation to the common structure or specific form that unites it with all the other members of its kind. In other words, we start to see the tulip in relation to its essence, instead of just seeing it through its particular visible features. And this understanding of a thing in terms of its essence makes it possible for us to judge how well the individual instantiates the common form of the species. Does this tulip have robust, green foliage? Is its stem strong? Is it blossoming? Instead of taking each of these facts indifferently, or as features that we happen to like on account of our aesthetic preferences, we can understand them as signs of the overall health or disease of the plant—clues as to whether that common form is well-instantiated in it, or is in the midst of decomposition. And we associate these characteristics, which are not subjective, but intrinsic to the thing in question, with an objective feature of the tulip as a tulip, which we call its degree of perfection.

The notion of an objective degree of perfection is quite extraordinary, because it tells us something real about the plant: that there is a real standard according to which we can tell whether a plant is doing “better” or “worse” objectively. In a way, this thought might seem very obvious, even trivial. After all, we talk about things being healthy or unhealthy all the time. But if we accept the reality of common forms and intrinsic degrees of perfection, this means that the notions of “good” and “bad” have at least a foothold of objectivity in the natural world. To put it differently, it proves wrong Hamlet’s famous dictum that “There is nothing either good or bad, but thinking makes it so.”^[William Shakespeare. Hamlet, Act II, Scene 2.] Of course, strictly speaking we have not proved just now the claim that there are intrinsic degrees of perfection, since a good philosopher would be able to raise a large number of objections to our analysis so far. The objections, to the extent that they are cogent, can (I believe) be answered, though the task of naming and replying to them is too much for the present. But at least we have shown how the notion of perfection integrates with the ordinary experience of reality, and makes sense of something very basic in that experience.

Degrees of Perfection Across Species

If we accept that there is an objective reality to the degrees of perfection of individual members of particular species, based on the fulness or strength of their individual instantiation of their specific forms, we have a universe full of different kinds of things, each with its own degree of perfection, relative to its species.

But an interesting problem occurs: in each case, the perfection of an individual thing is based on the comparison between that individual and the species as a whole. We judge something’s degree of perfection by comparing what this individual thing (a tulip, say) actually is, with what the best member of that species would be, as a member of that species. Does the tulip have wilted leaves? Well the best tulip would have very healthy robust leaves. Does the tulip have a strong stem? The best tulip would have a very strong stem. Can the tulip take in nutrients and reproduce? And so on. This kind of comparison, though, is always going to be relative to the species a thing belongs to. It makes no sense to judge whether a squirrel is perfect or not by comparing it to the ideal tulip. We cannot reasonably say “This squirrel must be diseased! It has no roots at all!” So this leaves us with a question: is perfection as an objective feature of things merely relative to individual species, or is there some sort of universal order of perfection, by which one species can be judged as more or less perfect than another as species?

In order to answer this question, we need to look more closely at the process by which we developed the idea of perfection in the first place. Our original notion of perfection was based on the commonness of the specific form shared between various individuals. This plant and that plant have the same structure, features, tendencies, and abilities. The integral makeup which constitutes the life (and life-cycle) of each plant is common to all the members of the species. Some investigative skill is necessary to identify this common specific form in the first place. We need to abstract what is essential from the peculiar features of each individual plant, and see the way different structural features, which are instantiated variously in the individuals, correspond to the analogous features and forms in other individual plants of the same species.

We can develop a more general notion of perfection by simply extending this analogical approach, and looking for greater or lesser degrees of unity and similarity across species. This oak tree may not be a tulip, but it shares with the tulip certain analogous forms and tendencies, such as the ability to grow and reproduce, or the possession of foliage and roots. By virtue of the real similarity of forms, we can group the two plants together, recognizing that while they may not have a common specific form, their like features unite them under the same genus or family of things.^[Note of course that our use of “genus” here does not correspond to the strict taxonomic use of the word among biologists, although the reader has probably noticed some similarity between them.] And once we establish a generic unity, we can use the strength of the generic community of species to identify trans-specific standards of perfection. For example, we might identify the genus “ferns”, and determine that one common feature of all the species which belong to this genus is that they produce spores. The particular features of the spores are left unspecified, but the general characteristic is known across the species as a definite sign of perfection.

As we expand the genera we choose to focus on, we can develop more and more universal notions of perfection. If we focus on “plants”, we can speak of autotrophy and photosynthesis. If we focus on “living things” we can speak of growth and reproduction. Finally we could generalize our consideration to substances as such, and we might identify unity or stability of form as signs of perfection.

However, as we follow this course, the usefulness of our analysis is progressively diluted by the breadth of the analogy. Though this method of forming trans-species standards of perfection does indeed give us a sense of what, across the board, makes things more or less perfect within their own species, we have a further question: Is there a hierarchy of species themselves? What would such a hierarchy be founded on?

Since the notion of perfection we have developed so far depends on the extent to which a thing stably retains or perfectly instantiates its specific form, one way to rank the perfection of species as such is by the way they possess their forms. For example, think about a heap of sand. As a thing, the heap of sand has certain determinate qualities: the arrangement of its parts into a whole, the material composition of those parts, the shape of the whole, its weight and density, etc. But the identity of the sand heap as an integral whole is not very robust. The sand heap has no ability to retain its form as it interacts with other things, or to restore itself, or grow, or reproduce itself by its own power. Nor does the sand heap as a whole add anything to the individual acts of its parts. As a heap, it is really just a collection of inert individuals.

Compare that sand heap to a plant. The plant is comparable to the sand heap in a number of ways: it has weight and density, is composed of a variety of distinct parts. But the plant’s form is sustained in the plant in a way that the sand heap’s is not. The plant is capable of taking things that are not part of it, and integrating them into its form. In contrast to the sand heap, being part of the plant genuinely adds something to the activity of these individual components. The properties of the plant’s parts are actualized by their participation in the plant’s life in a way that they would not be simply on their own, outside the plant. (For example, a single protein or bit of cellulose does little outside of a plant but decay, but within the plant it participates in a large number of extremely complex functions in coordination with the other plant parts.) Most extraordinarily, the plant is capable of perpetuating its form by reproduction. All of these features distinguish the form of the plant as a form from the form of the sand heap. We say that the form of the plant has more integrity as a form than the form of the heap—not only does the unity of the plant have more robustness than the unity of the sand heap, but the actuality of the plant in its natural behaviors enhances its material parts in a way that being part of a heap does not, and of course the specific form possessed by the plant has the ability to transcend its individual matter and communicate itself to the next generation.

This comparison between the formal integrity of a plant and a heap gives us the beginning of a hierarchy of perfections. Some things are more perfect than others, not just on account of the fulness with which they instantiate a common specific form, but also on account of the integrity of the form of which they are instances. The form of a plant is somehow more real than the form of a heap, in that it makes more of a real difference for the matter of the plant than the heap’s does for the grains of sand, and sustains itself with greater integrity regardless of the material conditions in which it finds itself, but perhaps most of all because it is partially independent of its individual matter. At the same time, the plant’s form contains in itself all the same sorts of formal perfections available to the sand heap—weight, substantiality, existence, etc.

Next, consider the difference between a plant and an animal, for example a cow. All the characteristics of the plant’s form that set it above the sand heap are shared by the cow as well: the ability to grow and nourish itself by integrating foreign matter into its own substance, the ability to heal, the ability to reproduce, the fact that being part of a cow elicits a variety of complex acts out of the otherwise inert components of the cow. But the form of the cow has a peculiar feature that the plant’s form does not—cows are capable of incorporating the forms of things around them into themselves not just by way of nutrition and growth, but also through sensation and imagination. A cow can be more than a cow, by seeing and hearing whatever is in its environment, and by retaining impressions of these things in its memory. Through perception and memory, the form of the cow becomes more than just the form of a cow, and also becomes the form of the grass, the places the cow roams, of other animals and people and things. Note that just as with the contrast between the plant and the sand heap, the difference here is not a simple amplification of a perfection already present in the the plant’s form, but the addition of a kind of formality not possessed at all by the plant. The form of the cow is in some way more real or more of a form than the form of the plant was, inasmuch as it rises above the form of its separate parts.

The cow is limited in its ability to incorporate the forms of other things into its own form, by its inability to analyze and abstractly understand its environment. If we pass from a cow to a rational animal, a human, we find not only the perfections which made the form of the cow more perfect than the form of the tulip—sensation, memory, desire, intention—but others as well. Humans are capable of understanding things not only in terms of their material forms, but also in terms of their structure, mechanics, essences, causes, etc. And they are capable of judging things not just in relation to their bodily appetites or fears, but in terms of their objective and intrinsic perfection. In other words, the abstract forms received in the mind of a human person are more real and capture more of the form than those received into the mind of a cow. They are not just sensory, but essential, and not just relative, but objective.

Let’s summarize our findings so far: first, we noted that it was possible to draw analogies across different kinds of things and find common standards according to which they could be said to be more perfect relative to their species. Then we compared four different kinds of things: a heap of sand, a plant, a cow, and a human. We found a common theme: some of these items have the characteristic perfections of others, but compound them by adding something extra: the plant can grow, heal, and pass on its form. The cow can add to its own form the sensible forms of things outside itself. The human can know and assess the real essences of things and their causes. The further we go in this series, the less attached a particular form is to the individual matter of a thing: the tulip’s form can endure after the matter of this tulip decays; the cow’s form is capable of receiving sensory forms of others into itself without becoming what it sees; the human’s form is capable of receiving the essences of things into itself, without losing its own essence. If we were to guess at a next step, it would involve something which was capable of overcoming the human dependence on matter (i.e. sense knowledge) to receive the forms of other things. Beyond that, a form which was in no way dependent on matter would be even more perfect.

Fortunately, we do not need to have a perfect understanding of the whole hierarchy of perfections in order to follow Thomas’s argument. The important points are (1) that there is a real hierarchy of species with respect to the intrinsic perfection of their forms, and (2) that the higher we go in this hierarchy, the more a thing’s form will have a reality independent of matter. However, our grasp of the hierarchy remains vague. Why should that be?

We can understand the intrinsic difficulty in mastering this universal hierarchy by thinking back again to the means by which we were able to establish a hierarchy of perfections in a tulip. We needed to have knowledge of a wide variety of tulips, and especially a knowledge of healthy tulips, in order to make any judgments about the relative perfection of any individual tulip. Supposing we only saw diseased tulips, would we be able to recognize accurately what constituted the perfection of a tulip? Only partially and indistinctly. Without having the highest element in this hierarchy of perfections available to analyze, it remains difficult to place all the other elements of the hierarchy relative to each other. And this is because in some way all judgments of perfection are dependent on knowledge of what is most perfect in a given genus.

To conclude, we will take up St. Thomas’s preferred example, and the fulness of the problem will become clear. In his statement of the Fourth Way, St. Thomas refers to the relationship between fire (which is essentially hot) and hot things in general. We compare the heat of one hot thing to another hot thing by implicitly holding them against the common standard of heat, which is fire. In St. Thomas’s mind, fire stands apart from all other kinds of heat, because for a fire, to be hot is part of the essence of what it is—you cannot have a fire without heat, since the rapid propagation of heat is what makes a fire a fire. Other hot things differ from fire in this respect: they have heat as an accidental attribute, but not as a constitutive feature of what they are.

Imagine a world in which we only ever saw things that were warm, but never any essential source of warmth, never any fire. We would have a sense that there was some ultimate source of heat, but nothing to refer back to, to explain the original warmth of all the cooling objects around us. Or imagine (as Plato famously has us imagine in his Republic) people whose whole experience in life consisted of seeing shadows of things dance along the walls of a cave. There might be a sense that something more real than the shadows lay behind them, but it would be difficult to grasp what that was.

With the universal hierarchy of perfections, we have exactly this problem: every perfection we witness in the world is relative to the being of a particular species or genus, and is therefore only a partial expression of absolute and universal perfection. We might find an excellent tulip, but that tulip does not embody perfection as such—only a certain tulip-like approximation of absolute perfection. And the same goes for all the other things we have discussed. But none of these things are perfect in and of themselves, just as none of them have the fulness of what it means to exist in and of themselves. And, once we realize this, we are ready to move to the final principle in St. Thomas’s argument.