Summa Theologiae 1, qq. 14-26

Question 14:  God's Knowledge
Question 21:  God's Justice and Mercy
Question 15:  God's Ideas
Question 22:  God's Providence
Question 16:  Truth
Question 23:  Predestination
Question 17:  Falsity
Question 24:  The Book of Life
Question 18:  God's Life Question 25:  God's Power
Question 19:  God's Will
Question 26:  God's Happiness
Question 20:  God's Love



Question 14:  God's Knowledge
  • General comments:   This question explores God's act of understanding, its nature and modes, God's knowledge of Himself and things distinct from Himself.  It is extremely important to read the whole question.  This will prevent misunderstandings of the sort people fall into especially about the nature of God's knowledge of the future, but about other aspects of St. Thomas's account of God's knowledge as well.  I will treat the question by grouping articles together under common themes.  (The treatment below presupposes familiarity with St. Thomas's general account of cognition;  see my commentary on question 12.

  • 14,1:  St. Thomas's main argument for the claim that God has knowledge is based on God's immateriality.  For things have cognition to the extent that they are able to have, in addition to their own form or esse, the form of other things as well.  But this ability requires faculties that have at least some distance from pure materiality.  Furthermore, God's knowledge can take on all the names of the best human knowledge, viz., intelligentia (grasp of evident first-principles), scientia (conclusions grasped with evidentness on the basis of evident first principles), sapientia (knowledge of ultimate first causes), and prudentia or consilium (good reasoning and judgment with respect to things to be done).  In each of these cases, however, we must exclude from God modes of signification, associated with these terms, that are in conflict with God's simplicity and perfection.

  • 14, 2-4:  Here St. Thomas explores the core nature of God's knowledge.  God's primary object of knowledge is Himself.  And, to make a long story short, the response to 14,4 concludes as follows:  "From everything that has been said so far, it is clear that in God the following are altogether one and the same thing:  (a) the intellect, (b) that which is understood, (c) the intelligible species, and (d) the very act of understanding.  Hence, it is clear that when God is claimed to be an intelligent being, no multiplicity is being posited within His substance."  14,2 begins with an overview:  A cognitive act is just the actuality of a cognitive species (sensible or intelligible), since the actuality of such a species is just the act of the faculty it informs or configures.  Thus, an act of the intellect is just the intelligible species of a given object insofar as that species is actually informing or configuring the intellect.  Now in our case such an act constitutes a perfection of our intellect, since the species brings the intellect from potentiality to actuality with respect to the cognition of the relevant object.  What's more, the object of cognition and its intelligible species are both distinct from our intellect; for the first objects of our intellection are material substances and their accidents, which obviously cannot exist in our intellect, and even their intelligible likenesses, which can exist in our intellect, are not always informing our intellect and hence are distinct from it.  In God, by contrast, there is (a) no movement from potentiality to actuality, (b) no perfecting of God's intellect by the intelligible species, (c) no distinction between the intellect and the object  understood, since God's primary object of understanding is His own intellective nature, and (d) no distinction between the intellect and the intelligible species, since God is, cognitively speaking, fully present to Himself through Himself insofar as He is actually understanding Himself.  So the act of understanding is not distinct from the object understood.  To grasp this more fully, notice that if there were an angel that existed from eternity, i.e., an angel that were created from eternity, his act of understanding would still be distinct from his substance and would be everlastingly bringing his substance to perfection.  This is not the case with God.  It is not just that God eternally understands Himself; it is that God's act of understanding is not in any way distinct from His substance and does not bring His substance -- even eternally -- to perfection.  Rather, His act of understanding is perfect in itself and has itself eternally present to itself as its intelligible object.  This boggles the imagination, since we naturally think of the intellect and act of understanding as distinct from the intelligible species and the object understood by means of the intelligible species.  In the case of God all these collapse together in a perfect act of understanding which is the divine essence.

    Because of this, God comprehends Himself, i.e., knows Himself as much as He is knowable.  And since He is perfect actuality, He is perfectly knowable to Himself, since both His cognitive power and the object understood by it are infinite or unlimited.  (Notice that in this He surpasses the blessed in heaven -- angels and saints -- who have a created light of glory and hence a finite capacity for knowing God, even though God Himself is likewise their intelligible species.  (Once again, see my commentary on q. 12, 2-11). This is a concrete way in which beatitude really is the sharing in God's own life, since this life is a life of knowing and loving.)

  • 14, 5-6 and 10-12:  In these articles St. Thomas talks about God's knowledge of created things, i.e., things distinct from Himself.  St. Thomas says that God knows these other things "through Himself," since in knowing Himself He knows all the things that He actually causes and is able to cause.  This will include every created substance and accident, since God's power is operative even in the actions of secondary causes.  For all the things He causes have perfections of one sort or another, and these are all traceable to God as their source and paradigm.  So He does not know these things by a sort of quasi-perceptual knowledge; rather, He knows them as an efficient cause.  (This will come out more fully in a. 8)

    To add more detail, God knows created things through a proper specific cognition and not just in general as beings (a. 6).  What's more, He knows each created thing as a singular thing, since His causal activity is responsible not just for general characteristics but for whatever individuates singulars (a. 11).  Hence, again, God does not have some sort of quasi-perceptual knowledge of things; rather, He knows creatures from the inside as the divine craftsman who is a cause -- either by Himself or with secondary causes -- of all being at every moment of time.  (I will return to this in a. 8, and it is an absolutely crucial point for understanding a. 13 on future contingents.)  In other words, He knows things because He knows what He wills to effect both by Himself alone and by Himself in conjunction with secondary causes.  So He knows, for any moment of time t, which causes are operating to effect at t whatever is effected at t.)  Furthermore, He knows evils because He knows the good that created things ought to have (a. 10), and He knows infinitely many singulars, not only by His knowledge of simple understanding, by which He knows metaphysically necessary truths about Himself and other things, including truths about what could exist at any point in time, but even by His knowledge of vision, that is, His knowledge of contingent truths, including truths about what does exist at each point in time (a. 12).

  • 14, 7 and 14:  These articles have to do with the mode of God's knowledge.  In art. 7 we learn, unsuprisingly, that God's knowledge is not discursive.  That is, God does not have to reason to conclusions in order to know truths about creatures; nor does he have to deliberate and make judgments about how to act.  Both of these features of our cognitive life are signs of finitude.  So God has scientia without having reasoned His way to it.

  • 14, 8-9 and 16:  

  • 14, 13 and 15:


Question 15:  God's Ideas
  • General comments



Question 16:  Truth
  • General Comments:  The first point to see here is that in the proper sense 'truth' attaches to the content of propositions.  (God does not compose and divide, but He does know the content of any possible proposition we might form.)  Hence, a proposition is true iff the world is as the proposition says it is.

    Notice that in God's case, all contingent truth is true because He wills it to be true.  (Issues surrounding created freedom need to be dealt with separately.)  So whereas there are certain truths, viz., the metaphysically necessary ones about His own essence and the possible entities He might create, that God sees with His knowledge of simple understanding (scientia simplicis intelligentiae), all the contingent truths that He knows by His knowledge of vision (scientiae visionis) are such that He knows them because He wills them to be true.  Once again, His knowledge of these truths is not akin to perceptual truth, at least as regards the connotation that perceptual knowledge has among its causes the things themselves.  God's knowledge is not caused in this way by the things themselves.  He knows the truth about things by virtue of His having willed a meticulous providential plan for the created world.

    The second point is that things themselves are true or false to the extent that they conform to the practical idea according to which they were made.  Hence, a created thing is true insofar as it conforms to the idea according to which God creates it.


Question 17:  Falsity

Question 18:  God's Life

Question 19:  God's Will

Question 20:  God's Love

Question 21:  God's Justice and Mercy

Question 22:  God's Providence
  • 1:  Providence (or disposition) is nothing other than the plan God has adopted for the created world.  (St. Thomas distinguishes between the plan itself (providence) and the execution of the plan (governance).)  Just as God's love, justice, and mercy are analogous to our virtues of the will, so providence is analogous to prudence, the virtue of the practical reason or intellect -- at least insofar as one can have prudence with respect to those persons things that fall under one's care.  So prudence is the plan by which God (a) orders all things toward their end and (b) orders the parts in the whole universe to one another.

  • 2:  The objections single out five classes of things that one might have reason to think do not fall under God's providence, viz., (a) that which happens randomly or fortuitously or by chance, (b) defects and evils; (c) that which happens by a necessity of nature; (d) the free actions of rational creatures; and (e) the acts of non-rational creatures.  

    The body of the question begins by citing those who believe that there is no providence and thus that everything that happens is in the end incidental or by chance. (Democritus and Empedocles are cited, but this is a very contemporary view as well, associated with the likes of Richard Dawkins.)  Next St. Thomas cites those who believe that corruptible things are subject to providence only in general ("according to their species") and not as individuals.  (Here he names Rabbi Moses.)  In contrast, St. Thomas asserts that God's causality is universal and thus extends to everything.  Now let's see how St. Thomas replies to the objections:

    (a)  In the realm of human affairs it is a common enough phenomenon that, say, someone arranges for two people to meet who might not otherwise have met.  The first agent in such cases might hope or expect that a certain result will follow.  (On the dark side, this is also the stuff of manipulation.)  In such cases, the result falls outside the intention of the two "particular" agents, but not outside the intention of the first "universal" agent.  So, too, St. Thomas contends, God as a first and universal agent adopts a plan for the world in which nothing happens by chance from His perspective.  It's all part of the plan, even if it falls outside the intentions or tendencies of particular agents.  This is a very powerful claim.  It allows for the possibility that even when certain particular effects occur randomly or by chance vis-a-vis their particular causes, they still do not fall outside of God's providence.  This would include effects whose immediate causes are indeterministic, as well as the effects of causes that just happen to intersect (as seems to be the case in the case of biological evolution).  So St. Thomas holds that chance or randomness is a relative notion, and that what is a chance effect with respect to one order of causes might not be a chance effect with respect to some other order.  More specifically, nothing is a chance effect with respect to the order of divine governance.  Every created effect is included in God's eternal plan for the world.

    (b) While particular agents strive for effects that are free of defects, a universal agent might well allow certain defects or evils to occur in order to promote the good of the whole.  For instance, sometimes parents will overlook a given small misstep on the part of their child if they judge that bringing this small transgression to the child's attention would, say, lead to results that damage the common good of the family.  (This happens a lot with teenagers.)  In the world of nature, many things that are bad for particular things are good for other particular things.  So such goods would be absent if no defects or evils were permitted.  The same holds for the moral sphere.



Question 23:  Predestination


Question 24:  The Book of Life
  • General Comments


Question 25:  God's Power

  • General comments

Question 26:  God's Happiness