Article 2 — Whether God’s essence or substance is the same as his existence

The second point of inquiry is whether God’s essence or substance is the same as his existence. (Parallel texts: ST I.3.4; SCG I.22, 52; In I Sent. 8.4.1; 8.4.2; 8.5.2; 34.1.1; In II Sent. 1.1.1; On Spiritual Creatures, a. 1; Compendium theologiae, ch. 11; On Being and Essence, ch. 5.)

Obj. 1: And it seems that it is not. For Damascene says, in On the Orthodox Faith 1: that God is, is evident to us; but what he is in substance and nature is utterly incomprehensible and unknown. (John Damascene, On the Orthodox Faith 1.1, 1.3 (PG 94:789–98).) Now, the same thing cannot be both known and unknown. Therefore, God’s existence is not the same as his substance or essence.

Obj. 2: But it will be replied that God’s very existence is unknown to us even as his substance is, as regards what it is.

On the contrary, these two questions are different, “Is he?” and “What is he?” And we know the answer to the former but not the answer to the latter, as evinced from the authority quoted. Therefore, that which in God corresponds to the question, “Is he?” is not the same as that which corresponds to the question, “What is he?” And existence corresponds to the former question and substance or nature corresponds to the latter.

Obj. 3: Again, it will be replied that God’s existence is known not through its very self, but through its likeness in the created.

On the contrary, in the created thing there is existence and substance or nature, and since it has both from God, it is like God in both respects because an agent produces its like. If, then, God’s existence is known through the likeness of created existence, it follows that his substance is known through the likeness of created substance; and thus, we would know not only that God is but also what he is.

Obj. 4: A thing is said to differ from another by reason of its substance, nor can one thing differ from another by reason of that which is common to all things; this is also why the Philosopher says that being should not be placed in a definition, since it would not differentiate the thing defined from anything else. (Aristotle, Metaphysics 3.3, 998b4–999a16.) Consequently, the substance of a thing that is distinct from other things cannot be its being, since being is common to all things. Now, God is something distinct from all other things. Therefore, his being is not his substance.

Obj. 5: Things are not distinct if they have not a distinct being. Now, the being of A is not distinct from B’s being, considered as being, but considered as in this or that nature. Hence, a being that is in a nature that is not distinct from its very being will not be distinct from any other being; and thus, it will follow, if God’s substance is his being, that he is the common being of all things.

Obj. 6: A being to which no addition can be made is the being common to all things. Now, if God is his own being, no additions can be made to his being, and then his being will be common to all. Consequently, he will be predicated of each thing and will enter into the composition of all things, which is heretical and contrary to the statement of the Philosopher, who says that the first cause rules all things without being mingled with them. (The Book of Causes, Proposition 20.)

Obj. 7: Nothing that implies concretion should be said of a thing that is utterly simple. Now, such is existence, for it would seem that existence is to essence as whiteness is to the white thing. Therefore, we should not say that God’s substance is his existence.

Obj. 8: Boethius says: whatsoever has being participates in that which is being so that it might exist, and it participates in something else so that it might be a certain thing. (Boethius, Hebdomads 6, ln. 41 (PL 64:1311).) Now, God exists. Therefore, besides his own being there is in him something else whereby he is something.

Obj. 9: That which is most imperfect should not be ascribed to God, who is most perfect. Now, existence is most imperfect, like prime matter, for just as prime matter may be determined by any form, so being, inasmuch as it is most imperfect, may be determined by all the proper categories. Therefore, as prime matter is not in God, so neither should existence be an attribute of the divine substance.

Obj. 10: That which is signified as an effect should not be ascribed to the first substance, which has no beginning. Now, such is existence, for every being has its existence through its essential principles. Therefore, it is unfitting to say that God’s substance is its own existence.

Obj. 11: A proposition wherein a thing is predicated of itself is known through itself. But if God’s substance is its own existence, the subject and predicate will be identical in the proposition “God exists.” Therefore, it will be a proposition that is known through itself; yet this seems to be false, since it can be demonstrated. Therefore, God’s existence is not his substance.

On the contrary (1), Hilary says in On the Trinity: in God, existence is not an accident but the subsisting truth. (Hilary of Poitiers, On the Trinity 7.11 (PL 10:208).) Now, that which is subsisting is the substance of a thing. Therefore, God’s existence is his substance.

Furthermore (2), Rabbi Moses says that God is a being but not in an essence, is living but not with life, is powerful but not with power, wise, but not with wisdom. (Moses Maimonides, The Guide for the Perplexed 1.53.) Therefore, in God, essence is not distinct from existence.

Furthermore (3), a thing is properly denominated from what it is, since the name of a thing denotes its essence and “whatness,” as is held in Metaphysics 4. (Aristotle, Metaphysics 4.4, 1006a26–1007b18.) Now, of all God’s names, He who is is the most appropriate to him (Exod 3:14). Hence, as this name is given to him in respect of his existence, it would seem that God’s very existence is his essence.

I answer that in God there is no distinction between existence and his substance. In order to make this clear, we must observe that when several causes producing various effects produce one effect in common, aside from their various effects, they must produce this common effect by the power of some higher cause to which this effect properly belongs. The reason for this is that, since a proper effect is produced by a particular cause in respect of its proper nature or form, different causes having different natures and forms must have their different proper effects.

Whence, if they have one effect in common, this is not the proper effect of any one of them but of some higher cause by whose power they act; for example, it is clear that pepper, ginger, and the like, which differ in their constitutions, have the common effect of producing heat, even though each has its peculiar effect differing from the effects of the others. Hence, we must trace their common effect to a prior cause to which that effect properly belongs, like fire. Likewise, in the heavenly movements, the sphere of each planet has its peculiar movement, and besides this they have all a common movement that must be the proper movement of some higher sphere that causes them all to revolve with the daily movement.

Now, all created causes have one common effect, which is being, although each one has its peculiar effect whereby they are differentiated; for heat makes a thing to be hot, and a builder gives being to a house. Accordingly, they have in common the fact that they cause being, but they differ in that fire causes fire and a builder causes a house. There must, therefore, be some cause higher than all others by the power of which they all cause being and whose proper cause is being. And this cause is God.

Now, the proper effect of any cause whatsoever proceeds from the latter according to a likeness of its nature. Therefore, being must be the substance or nature of God. For this reason, it is stated in The Book of Causes that none but a divine intelligence gives being, and that being is the first of all effects, and that nothing was created before it. (The Book of Causes, Proposition 9.)

Reply Obj. 1: “Being” and “to exist” may be taken in two ways, as is clear in Metaphysics 5. (Aristotle, Metaphysics 5.7, 1017a7–35.) Sometimes they signify the essence of a thing, that is, the act of existing; and sometimes they denote the truth of a proposition, even in things that have no existence; for example, we say that “blindness exists” because it is true that a man is blind. Accordingly, when Damascene says that God’s existence is evident to us, the existence of God is taken in the second sense and not the first. For in the first sense, God’s existence is the same as his essence, and as his essence is unknown, so also is his existence. In the second sense, we know that God is because we conceive this proposition in our mind from his effects.

Reply Obj. 2–3: This suffices for the replies to the second and third objections.

Reply Obj. 4: God’s being, which is his essence, is not universal being; rather, it is a being distinct from every other being whatsoever. Whence by his very being God is distinct from every other being.

Reply Obj. 5: As stated in The Book of Causes, God’s being is individualized and distinct from every other being by the very fact that it is self-subsistent being and is not something additional to a nature that is distinct from its very being. (The Book of Causes, Proposition 4.) Now, every other being that is not subsistent must be individualized by the nature and essence that subsists in that being. And of such beings it is true that the being of A is distinct from the being of B by the fact that it is the being of another nature; for example, if there were one heat existing of itself without matter or subject, by that very fact it would be distinct from every other heat, just as heat that exists in a subject is not differentiated otherwise than by its subjects.

Reply Obj. 6: The being to which no addition is made is common being, though the possibility of addition thereto is not incompatible with its account; rather, the divine being is a being to which no addition can be made, and this enters into the very account of the divine being; therefore, the divine being is not common being. For example, even to animal in common there arises no addition, in its own account, of the difference rational; yet it also does not belong to its account that no addition can be made to it; for this latter enters into the account of irrational animal, which is a species of animal.

Reply Obj. 7: The mode of signification of the names we give things is consequent upon our mode of understanding, for names signify the concepts of our intellect, as is said at the beginning of On Interpretation. (Aristotle, On Interpretation 1.2, 16a19–b5.) Now, our intellect understands being according to the mode in which it finds it in things here below, from which it gathers its knowledge, and wherein being is not subsistent but inherent. Now, reason tells us that there is a self-subsistent being; therefore, although the term “being” has a signification by way of concretion, yet our intellect in ascribing being to God soars above the mode of its signification and ascribes to God the thing signified, but it does not ascribe the mode of signification.

Reply Obj. 8: The saying of Boethius refers to things that have being by participation and not by their essence; for that which has being through its own essence, if we stress the force of the terms, should be described as being itself rather than as that which has being. (Boethius, Hebdomads 6, ln. 41 (PL 64:1311).)

Reply Obj. 9: Being, as we understand it here, signifies the highest perfection of all, and the proof is that act is always more perfect than potency. Now, no signified form is understood to be in act unless it be supposed to have being. Thus, we may take human nature or fiery nature as existing potentially in matter, or as existing in the power of an agent, or even as in the intellect, but when it has being it becomes actually existent. Therefore, it is clear that being as we understand it here is the actuality of all acts, and therefore, the perfection of all perfections. Nor may we think that being, in this sense, can have anything added to it that is more formal and determines it as act determines potency, because being in this latter sense is essentially distinct from that to which it is added and by which it is determined. But nothing that is external to being can be added to being, for nothing is external to it except non-being, which can be neither form nor matter. Therefore, being is not determined by something else as potency by act but rather as act by potency, since in defining a form we include its proper matter in the place of its difference; thus, we define a soul as the act of an organic physical body. Accordingly, this being is distinct from that being inasmuch as it is the being of this or that nature. For this reason, Dionysius says that, though things having life are nobler than those that merely have being, yet to exist is nobler than to live; for living things have not only life but along with their life they have being as well. (Pseudo-Dionysius, The Divine Names 5.1 (PG 3:815–16).)

Reply Obj. 10: According to the order of agents there is an order of ends, such that the last end corresponds to the first agent and, in due proportion, other ends to other agents in their order. Take, for example, the ruler of a state, the commander of the army, and a single soldier: the ruler is clearly the first in the order of agents, at whose orders the commander goes forth to the war, and under him is the soldier, who engages in hand-to-hand combat at the orders of his commander. Now, the end of the soldier is to overcome his opponent, and this is directed yet further to the victory of the army, which is the end of the commander, and this again is directed to the welfare of the state or kingdom, which is the end of the ruler or king. Accordingly, being, which is the proper effect and end of the activity of the first agent, must occupy the position of last end. Now, although the end is first in the intention, it is last in execution; and it is the effect of other causes. Therefore, created being, which is the proper effect corresponding to the first agent, is caused by other principles, even though the first cause of being is the first principle of all.

Reply Obj. 11: A proposition may be known through itself of itself and yet not known through itself to this or that individual, namely, when the predicate belongs to the account of the subject, which account is unknown to him; for example, if someone did not know what a whole is, he would not know this proposition through itself, “A whole is greater than its part.” For such propositions become known when their terms are known, as is said in Posterior Analytics 1. (Posterior Analytics 1.1, 71a11–23, 71a34–b5; 1.6, 75a24–37.) Now, this proposition, “God is,” is of itself known through itself, since the same thing is in both subject and predicate, but with regard to us, it is not known through itself, because we do not know what God is; whence, for us, there needs to be a demonstration, though not for those who see God’s essence.