Aristotle begins his Metaphysics by saying something about human nature, “All men by nature desire to know” (Met. A, 980b22). If it is by our nature, we might be so bold as to count it among our essential properties. But, what does it mean to “desire”? And in particular, what does it mean to desire knowledge? Socrates provides the following account of “desire” in Plato’s Symposium:
Then this is what it is to love something which is not at hand, which the lover does not have: it is to desire the preservation of what he now has in time to come, so that he will have it then… So such a man or anyone else who has a desire desires what is not at hand and not present, what he does not have, and what he is not, and that of which he is in need; for such are the objects of desire and love… (Symposium 200d-e).
If this is so, to desire knowledge is to love something that is not at hand. It is to want and to keep knowledge. This also means that to have and to hold knowledge satisfies the desire for it. Such a situation is reflected in a quote that I saw posted on the blog of a friend and colleague. The quote is from an article by Lorraine Daston. The quote is as follows:
Therein lies the paradox of wonder: it is the beginning of inquiry (Descartes remarks that people deficient in wonder “are ordinarily quite ignorant”), but the end of inquiry also puts an end to wonder. The marvel that stopped us in our tracks—an aurora borealis, cognate words in languages separated by continents and centuries, the peacock’s tail—becomes only an apparent marvel once explained. Aesthetic appreciation may linger (it is no accident that the vernacular descendants of the Latin word for wonder, admiratio, convey esteem), but composure has returned. We are delighted but no longer discombobulated; what was once an earthquake of the soul is subdued into an agreeable frisson. At least within the classical philosophical tradition, from Aristotle to Descartes (and arguably beyond, to Adam Smith and even to Kant), this negative correlation between wonder and explanation is strong and tenacious. Explanation lies at the heart of the distinction between marvels and miracles in the Latin Christian tradition. What is the difference? Thomas Aquinas answers: marvels (mirabilia) are inexplicable to most but not all people (e.g. the eclipse that transfixes the ignorant peasant but not the learned astronomer); miracles (miracula) are inexplicable to everyone. Wonder is a barometer of ignorance: the learned experience it rarely; God, never. Wonder is not only a peculiarly human passion; it is also one that, at least on this account, underscores the limits of human knowledge. The more we know, the less we wonder.
Daston’s thesis is actually moves in quite the opposite. She holds that our understanding of “wonder” has evolved and adapted such that wonder is not snuffed out by knowledge, but is generated by knowledge. Not to disregard her thesis, but I do want to consider this more ancient notion of wonder for a moment. As Aristotle tells us that:
…it is owing to their wonder that men both now being and at first began to philosophize; they wondered originally at the obvious difficulties, then advanced little by little and stated difficulties about the greater matters, e.g. about the phenomena of the moon and those of the sun and the stars, and about the genesis of the universe. And a man who is puzzled and wonders thinks himself ignorant (whence even the lover of myth is in a sense a lover of wisdom, for myth is composed of wonders); therefore since they philosophized in order to escape from ignorance, evidently they were pursuing science in order to know, and not for any utilitarian end (Met. A, 982b11-22).
Now if naturalism is true, then the world may be filled with marvels, perhaps very inexplicable marvels like consciousness, but it is not filled with that which is, in principle, inexplicable for us. This does not mean that, on naturalism, reality could ever be fully disenchanted. There seems to be practical limitations that would prevent us from explaining everything. At the same time, it does mean that the relationship between reality and our minds is such that it is merely accidental that we have the desire to know. We could, in principle, uncover all of the marvels that exist and satisfy this desire. In snuffing it out, the desire would cease to exist in us. So actually having the desire for knowledge would be accidental if everything in existence were knowable for us. But, if the actuality of desiring knowledge is an essential feature of the human intellect, then there must be some sense in which, in principle, reality is not fully knowable or explicable. This would be true if there were true supernatural miracles and mysteries. The argument would be as follows:
1. All humans actually desire knowledge essentially. [Premise]
2. If naturalism is true, then the actuality of human desire for knowledge is accidental. [Premise]
3. If the actuality of human desire for knowledge is accidental, then it is not the case that all humans actually desire knowledge essentially. [Premise]
4. Therefore, it is not the case that naturalism is true.
Now there are a few ways the naturalist could object:
Objection 1: Though naturalism is true, there are some natural mysteries that are unknowable, intractable, or inexplicable in principle. For instance, we may not be able to know or understand why there is something rather than nothing. We might not be able to know if there is a multiverse, or what occurred before the big bang. We might not be able to explain consciousness. We might not be able to fully explain those soft sciences that involve human behavior (owing to human freedom, or chaos, or indeterminism).
Reply to 1: It seems to me that if there are per se mysterious features of reality, there is no reason to be a naturalist. I take naturalism to be the claim that all of reality can be accounted for by the natural sciences. If certain aspects of reality are not merely really difficult to account for by natural scientific methodology, but intrinsically and essentially beyond the scope of the natural sciences, then I would say that metaphysical naturalism is a failure (or just a vacuous metaphysical position).
Objection 2: One could bite the bullet and say that humans don’t actually desire knowledge in an essential way. It is merely an accidental property of our mental constitution. Perhaps the capacity to desire knowledge is essential to humans, but not the actuality.
Reply to 2: This seems like a more powerful objection than the first. Humans satisfy desires all the time. In fact, there is a famous argument from desire put forth by C.S. Lewis, which argues that all natural desires have an object in reality that can satisfy their desires. So it might seem that the existence of the humanly unknowable or inexplicable contradicts this premise. However, the argument from desire does not hold that all desires are satisfied. The hungry child who is a victim of famine may never get the food that satisfies her, though such food exists. There may be knowledge that exists, say in the mind of an omniscient God, that we desire, but can never possess (due to our natural limitations). So the fact that we cannot completely satisfy our desire for knowledge, and that all natural desires have corresponding objects, does not mean that there is nothing to know when it comes to the truly miraculous or mysterious.
Now one might say that nothing really is truly miraculous or mysterious. We can, in principle, explain everything naturally, we are just limited by time and other pressing needs. And one might even be willing to grant that humans possess the capacity to desire wisdom in an essential way (the potential/power to desire knowledge), but that capacity can be fulfilled in the following way: we actually desire knowledge when we are actually ignorant and potentially in a state of knowledge. When we change to a state of potentially desiring knowledge, we are actually in a state of knowledge and are potentially ignorant. We could, in principle, be in a state of potentially desiring all knowledge, if we can be in a state of actually knowing all things (potentially ignorant). So this objection amounts to the claim that we humans have the capacity for omniscience essentially (perhaps as a collective and through various mediums of storing knowledge).
I find this response too strong. I don’t think any naturalist would want to hold it either. Ultimately, I think the idea that humans will always be in some actual state of desire for knowledge rests on a certain intuition about the relationship between the human capacity for knowledge and the way reality is. My intuition is that not everything can be known by us. And this, to me, stands in the way of metaphysical naturalism. For what else is the naturalist claiming than that reality falls completely under the genus “natural”. And so reality can be completely defined and comprehended by our intellects. If this is not the naturalist’s claim, then I am not sure what naturalism is supposed to be (at times I suspect it really is just the denial of souls and God, but that is not a positive metaphysical position).
One might point out that we don’t always actually desire knowledge (small babies, the sleeping, etc.). Furthermore, some desire knowledge more than others. Doesn’t this indicate that, while the capacity to desire knowledge may be essential, the actuality of that desire can change and is accidental to our circumstances and personal dispositions. A response might be to consider Aristotle’s musical man. In a sense, one can argue that all humans, sleeping, and even the very young, have a natural desire to know is a first actuality insofar as one has an intellect that is always deprived of knowledge that it desires to have. The second actuality might be something like the active awareness of that desire, which motivates one’s investigations. Even the very young explore their world with their eyes, hands, and mouth. So, I don’t think it is the case that even the very young escape this state.
The following argument occurred to me the other day. I do not know if anything similar has been argued (please let me know in the comments, if you are aware of something similar). I call it an argument from uniqueness. Basically, the argument is:
1. If God does not exist, necessarily it is not the case that there is an essential property, uniqueness, that is exemplified.
2. Possibly, the essential property, uniqueness, is exemplified.
3. Therefore, God exists.
A defense of the premises:
I argue that (1) is true, given that I am understanding “God” in the Thomistic sense (I am appealing to concepts specified by Thomas in the Summa Theologiæ). Now, Uniqueness is attributed to God in many theistic traditions, but let me stipulate what I think Thomas means, and why I think (1) follows from it.
Some theists understand the “uniqueness” of God to mean that only God has all perfections, i.e. there is no other being that is omniscient, omnipotent, and morally perfect. But, I take Thomas to be saying something a bit more radical than that. For, the God Thomas describes is said to be the exemplification of Being itself:
God is His own essence, as shown above (Article 3) if, therefore, He is not His own existence He will be not essential, but participated being. He will not therefore be the first being–which is absurd. Therefore God is His own existence, and not merely His own essence. (ST. I 3.4).
So, the first point is that God is the only being that is its own act of existence. All other sorts of beings are participated being, which is to say that they receive the act of being from without and not per se. What’s more, since God’s essence is existence, God does not belong to any genus. Thomas provides three arguments for why God lacks a genus, and this relates directly to why God is unique (ST. I.3.5):
First, because a species is constituted of genus and difference. Now that from which the difference constituting the species is derived, is always related to that from which the genus is derived, as actuality is related to potentiality. For animal is derived from sensitive nature, by concretion as it were, for that is animal, which has a sensitive nature. Rational being, on the other hand, is derived from intellectual nature, because that is rational, which has an intellectual nature, and intelligence is compared to sense, as actuality is to potentiality. The same argument holds good in other things. Hence since in God actuality is not added to potentiality, it is impossible that He should be in any genus as a species.
Secondly, since the existence of God is His essence, if God were in any genus, He would be the genus “being”, because, since genus is predicated as an essential it refers to the essence of a thing. But the Philosopher has shown (Metaph. iii) that being cannot be a genus, for every genus has differences distinct from its generic essence. Now no difference can exist distinct from being; for non-being cannot be a difference. It follows then that God is not in a genus.
Thirdly, because all in one genus agree in the quiddity or essence of the genus which is predicated of them as an essential, but they differ in their existence. For the existence of man and of horse is not the same; as also of this man and that man: thus in every member of a genus, existence and quiddity–i.e. essence–must differ. But in God they do not differ, as shown in the preceding article. Therefore it is plain that God is not in a genus as if He were a species. From this it is also plain that He has no genus nor difference, nor can there be any definition of Him; nor, save through His effects, a demonstration of Him: for a definition is from genus and difference; and the mean of a demonstration is a definition. That God is not in a genus, as reducible to it as its principle, is clear from this, that a principle reducible to any genus does not extend beyond that genus; as, a point is the principle of continuous quantity alone; and unity, of discontinuous quantity. But God is the principle of all being. Therefore He is not contained in any genus as its principle.
So, since God is not in any genus, there cannot be other beings that have the same essence, or other kinds of beings that are their own act of existence. Hence Thomas writes (ST. I.11.3):
First from His simplicity. For it is manifest that the reason why any singular thing is “this particular thing” is because it cannot be communicated to many: since that whereby Socrates is a man, can be communicated to many; whereas, what makes him this particular man, is only communicable to one. Therefore, if Socrates were a man by what makes him to be this particular man, as there cannot be many Socrates, so there could not in that way be many men. Now this belongs to God alone; for God Himself is His own nature, as was shown above (Question 3, Article 3). Therefore, in the very same way God is God, and He is this God. Impossible is it therefore that many Gods should exist.
To say that God does not exist is to say that the “being who is its own act of existence” does not exist. But, if such a being were to exist, necessarily it would exist, since there would be no potential in its essence for its non-existence. By contraposition, God’s non-existence entails God’s impossibility—there would be neither the potential nor the actuality of anything being its own act of existence. So, if God does not exist, it is not possible that there is a being who is its own act of existence. And if it is not possible that there is a being who is not its own act of existence, then all beings that do exist would fall under one category of being or another. Thus, if every being falls under one category (highest genus) or another, no being is essentially unique. For, every being would the same at least with respect to other members that fall under the same category, e.g. one quantity would not be uniquely a quantity, since another quantity exists.
Put simply, if God does not exist, everything that exists would be the same as something else at least with respect to the highest genera. Thus, God’s non-existence entails the impossibility of essential uniqueness.
My defense of (2) will be much more brief. There is nothing within the concept of essential uniqueness that implies a contradiction. Therefore, it is not impossible that essential uniqueness is exemplified. In fact, our discussion of the first premise provided a coherent account of how essential uniqueness could be exemplified, namely if a being that is its own act of existence were to obtain. Nothing in that discussion seemed inconsistent, so there is, at the very least, prima facie plausibility that the second premise is true.
From these two premises, the conclusion necessarily follows that God exists. The deduction is as follows:
θx – x is a Thomistically defined divine being
U – Uniqueness
Π – Essential Property
1. ~(∃x)θx → □~(∀x)(∃Π)[Πx & (Π = U) (premise)
2. ◊(∀x)(∃Π)[Πx & (Π = U)] (premise)
3. ~~◊(∀x)(∃Π)[Πx & (Π = U)] (2 DN)
4. ~□~(∀x)(∃Π)[Πx & (Π = U)] (3 MN)
5. ~~(∃x)θx (1,4 MT)
6. (∃x)θx (5 DN)