Lesson 4: The Philosophy of Nature


Why Not Begin with Metaphysics?

Writing shortly after World War II, Jacques Maritain contrasted Thomism with the then modish Existentialism in a little book called in English, Existence and the Existent. His primary target was Jean-Paul Sartre, whose little book Existentialism is a Humanism had given a popular statement to the new philosophical craze. What James Collins called Sartre's "postulatory atheism" led to a stark contrast. Theists see God as a maker and creatures as possessing the nature God gave them; this nature provides a measure of the flourishing of the one having that nature. In Sartre's lapidary phrase, for the theist essence precedes existence. But things are quite different for the atheist. Without a maker there is no essence and without an essence there is no antecedent guide for action. I cannot say, for example, "Well, a human being ought to do such and such," since this presupposes that there is a human nature to which appeal can be made to ground the judgment. Without such a nature, what-I-am is freely constructed by the acts I perform. Existence precedes essence.

As Cole Porter put it, Anything goes. There are no precepts or prohibitions to which my actions must conform. I am free through and through. Sartre did not advance this position with libertarian -- or libertine -- glee, as if, being able to do anything I wished, I would be happy as a lark. Freedom is a burden because, sans nature, it is without excuse. Total freedom entails total responsibility. This was the view Maritain wished to counter with an equally popular restatement of the outlook he had learned from Thomas Aquinas.

Since Sartre had spoken of essence and existence, Maritain is led to speak of what Thomas had had to say of this pair. But the student of Thomas will have difficulty matching what Maritain says with what Thomas taught. This is nowhere more evident than in the discussion of the "intuition of being" and its relationship to metaphysics.

The act of existing is the key to Thomas's philosophy, we are told, and it is something super-intelligible which is revealed in the judgment I make that something exists. "This is why, at the root of metaphysical knowledge, St. Thomas places the intellectual intuition of that mysterious reality disguised under the most commonplace and commonly used word in the language, the word to be; a reality revealed to us as the uncircumscribable subject of a science which the gods begrudge us when we release, in the values that appertain to it, the act of existing which is exercised by the humblest thing -- that victorious thrust by which it triumphs over nothingness" [Image Books edition, 1957, pp. 28-29].

Maritain seems to say that existence is the subject of metaphysics, but then seems not to say this, by adding "uncircumscribable." But it is the grasp of existence that he takes to be the key to metaphysics. A philosopher who is not a metaphysician is not a real philosopher and it is the intuition of being that makes the metaphysician.

I mean the intuition of being in its pure and all-pervasive properties, in its typical and primordial intelligible density; the intuition of being secundum quod est ens. Being, seen in this light, is neither the vague being of common sense, nor the particularized being of the sciences and of the philosophy of nature, nor the de-realized being of logic, nor the pseudo-being of dialectics mistaken for philosophy [p. 29].

There is much that is familiar here for the student of Aquinas, but there is strangeness as well. On the one hand, metaphysics is concerned with being as being, whereas the sciences and philosophy of nature are concerned with a particular kind of being. No mention is made of mathematics, but the way in which logic is described might be taken to do service for that. Moreover, Maritain is clear that the intuition of being required for metaphysics is not the sort of vague grasp of being everyone has. It is an achievement. But what kind of an achievement is it?

Maritain's account becomes progressively more obscure and rhetorically charged. "It is being, attained or perceived at the summit of abstractive intellection, as an eidetic or intensive visualization which owes its purity and power of illumination only to the fact that the intellect, one day, was stirred to its depths and trans-illuminated by the act of the act of existing apprehended in things..." [29-30]. There are many paths to this intuition. It may spring "like a kind of natural grace at the sight of a blade of grass or a windmill, or at the sudden perception of the reality of it self..." [30]. This is contrasted somewhat obscurely with the way Thomas Aquinas gained this intuition. In the end it is a boon, a gift, fortuitous, a kind of docility to the light.

I cite this only because it suggests a way around the order of learning we have seen in Thomas Aquinas. For reasons to which we will return more than once in what follows, for Thomas, the possibility of a science between the special science depends on demonstrations within the philosophy of nature that conclude to the existence of something apart from matter. On the basis of such proofs, one knows that to be and to be material are not identical. Absent such proofs, Thomas says, philosophy of nature would be wisdom and the culminating science of philosophy. Talk of an intuition, which might be triggered by a blade of grass, suggests another route into this recognition that some being is not material and thus that being as being is not identical with being as material. Whatever else might be said of this, it must be said that it is quite different from Thomas's view. Accordingly, it is somewhat disingenuous to present it as Thomistic or as merely a variation on what we find in Thomas.

I single out Maritain on this matter because of the earned authority he has in the Thomistic Revival. There may be one or two others who have done as much to make Thomas audible to the contemporary ear, but no one has exhibited the range and depth that we find in Maritain's work. It was only fitting that he should step forward and address the rise of Existentialism from the vantage point of Thomism. In commending metaphysics, Maritain is not alone in bypassing the route laid out by Thomas. What is the cause of this discontent?

The Reasons for this Discontent

A glance at the history of western thought provides the answer. It is one of the great givens that with Copernicus and Galileo a turn was taken in the study of nature which effectively rendered obsolete the Aristotelian system that had preceded it. That this received opinion, like so many others, requires profound emendation will be clear to you from Father Wallace's course in philosophy of nature. Nonetheless, something happened and the subsequent advance of the sciences has carried them increasingly away from philosophy, or at least from philosophy as understood by Aristotle and St. Thomas.

One of the key issues facing the Thomistic Revival was precisely the relationship between philosophy and the sciences. If one simply assigned to the natural sciences, as they had developed, all the tasks that had fallen to the philosophy of nature, one might then look to the sciences for some intimation that the objects of those sciences do not exhaust reality. From time to time, it is maintained that a development in the sciences has opened up the mind to a reality beyond the physical, but the dominant view has tended to be that, given its methodology, natural science will simply deal with the things which come within the range of that methodology and remain agnostic about whatever does not.

Positivism is a more assertive form of this last view. Not only must the sciences stick to the things which fall within its range, whatever does not fall within the range of the natural sciences can safely be regarded as nothing. Thus the rise of science, far from providing aid and comfort to metaphysics, took the path indicated by Thomas. If physical reality is synonymous with reality, then natural science is wisdom and the goal and term of philosophy.

With knowledge of nature no longer serving as the handmaid of metaphysics but setting itself up as a rival, the philosopher who wished to retain anything like a classical metaphysics had a problem. One solution is that suggested by Maritain's talk of an intuition of being. The suggestion is that, by many paths, on the basis of one kind of fortuitous experience or another, one has an intuition of being as being and thus is in possession of the subject of metaphysics.

Ens Primum Cognitum

Maritain is careful to distinguish the intuition of being from the vague grasp of being that anyone has. Anyone aware of anything at all is aware of being since being is the most general term applicable to whatever is. Being in this sense, ens ut primum cognitum, being as the first and most obvious thing the mind grasps, is distinguished from ens inquantum ens, the subject of metaphysics. Both Cardinal Cajetan and John of St. Thomas engage in extensive discussions of this contrast. The transition from the one to the other is made in the manner taught by Aquinas. The vague awareness of our surroundings leads on to a reflective effort to grasp the nature of physical things and this in turn leads to the proof of the prime mover and the proof of the immateriality of the human soul. Those proofs establish that to be and to be physical are not identical and thus provide a new sense to the phrase, being as being.

There is no reason to hold that what is called scientific methodology represents the only means of knowledge of nature. Indeed, as I developed in one of the taped lectures, it can be argued that scientific knowledge of the world presupposes what may be called pre-scientific knowledge, without which the scientific account would be meaningless, that is, without referent. If I do not have knowledge of the world before I begin its scientific study, I would have no object of study. Such pre-scientific knowledge, insofar as it simply means knowledge of the natural world by means other than scientific methodology, provides the charter for the continued existence of the philosophy of nature as Aristotle and Thomas understood it. This is not to say that Aristotelian cosmology is untouched by subsequent developments. That would be ridiculous. What it does say is that there is scientific knowledge of nature, where scientific bears its Aristotelian meaning, prior to and independent of scientific knowledge.

On this basis, there remains a discipline that can provide the proofs on the basis of which we speak of being as being as the subject of a new science beyond the particular sciences.

The Wonder at Being

That being said, we can return to the notion of an intuition of being, that is, of a sudden epiphany at how astounding it is that things exist. This wonder is often summed up in the questions, "Why is there anything at all rather than nothing?" And one is drawn toward what the poets have said about their astonishment at things. Paul Claudel spoke of poetic knowledge as a connaissance and then, by breaking the word down into co-naitre suggested that the poet somehow comes to be with what he experiences, has an affinity with it that goes beyond a merely conceptual grasp. Gerard Manley Hopkins spoke of poetic inscape and became enamored of what he understood Duns Scotus to mean by haecceitas, the thisness that sets one being off from another and makes it unique.

Such accounts carry their full weight if the being grasped is sensible being. Indeed, poets are likely to respond by preference to what is given to the senses. There may even be some intimation of immortality provided by poetic experience, but it would be chancy indeed to regard this as the basis for the science of metaphysics.

As both Plato and Aristotle insisted, philosophy begins in wonder. The objects of wonder are first of all obvious things -- the burning of fire, an eclipse -- and we are both in awe of such things and seek to know how they happen. What is clear is that the requisite wonder is operative in our response to the physical world and is not as such any argument for their being things beyond the physical.

Philosophers such as Husserl and Heidegger and others, some non-German, have lamented the way in which modern technological society cuts us off from existing things. Reality becomes encrusted with familiarity and the quotidian. When this is so, various devices must be employed to wake up the mind to reality, to enable us to see what lies before our eyes. But in grasping what lies before our eyes and marveling that it exists we are not yet provided with the presuppositions of metaphysics.

Suggested Reading Assignment

Aristotle's Metaphysics, Book Two, in its entirety.

This is a short book but full of insights. Of course you will want to consult Thomas's commentary on it.

Suggested Writing Assignment

Contrast the two Sartrean slogans, "existence precedes essence" and "essence precedes existence." What does "existence" mean in these phrases? What is the point of the contrast?


You would do well to get hold of Maritain's Existence and the Existent from a library. It is currently out of print but will eventually appear in the Notre Dame edition.


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