Commentaria in Primam Partem Summae Theologiae

In the title, it must be noted what is meant by the name of speculative and practical science. Speculative science is called that whose proper end is nothing other than to know; practical science, however, is that whose proper end is to act, whether by the appetite of operation or by the executive power, Aristotle saying in Book II Ethic.¹: we undertake discourse of this kind not in order that we may know, but in order that we may act, etc.

II. In the body, two conclusions². The first is: Theology is neither purely practical nor purely speculative; but higher, comprehending in itself in a more eminent way both the character of the practical and of the speculative.

III. Before the conclusion is proved, so that the meaning of the conclusion may be evident, know that the practical and the speculative are neither essential differences, nor quasi-passions consequent upon essential differences, first dividing science in general: just as neither sight nor hearing are differences first dividing sense in general. But as sense is first divided into common and proper sense, and then proper sense is divided into sight, hearing, etc.; so science is first divided into infinite and finite science, and then finite science is divided into speculative and practical. And the reason for this is that one finite formal ratio of an object cannot have both conditions—that it be that from which a rule of operating is taken, and that it be in itself knowable—even if no rule of action could be taken from it: but these two conditions must be founded upon two finite formal rationes, as appears inductively. But if the formal ratio of some knowable object is infinite, it already comprehends both conditions in itself by its infinity, in a higher manner than they exist in finite things: because what is dispersed among lower things is anticipated unitedly in the higher. And therefore, as beyond the proper senses there is given a sense of a higher order, which is neither sight nor hearing, etc.; so beyond the speculative and practical sciences there is given a science of a higher order, neither speculative nor practical, but eminently containing both. And according to this sense the conclusion is understood. Hence in the text it is said that, although in the physical sciences one thing is speculative and another practical (that is, the practical and the speculative make otherness, which is a substantial difference); sacred doctrine nevertheless, being one, comprehends both, as being a science of a higher order.

IV. The conclusion is therefore proved in the text as follows. Sacred doctrine, being one, extends itself to those things that pertain to the speculative and the practical sciences: therefore it is itself higher, comprehending both under itself. – The antecedent is proved from the preceding article. Sacred doctrine attends to one common reason³ of things speculable and operable, namely insofar as they are divinely revelable: therefore. – The consequence is proved: because this science is like the science of God, who by one and the same science knows himself and his works: therefore.

V. Note here, for the clarity of the text, three things. First, concerning the proof of the consequence from the antecedent already proved: that this proof is excellent, and a priori, and not by way of an argument from analogy. For since our theology is nothing other than the impression and proper seal of the divine science (because both are about God insofar as God: and this one is derived from that one under its own, though small, participation of its light), it follows that the unity of the former entails the unity of the latter, and the height of the former, whereby it extends to both genera, entails the height of the latter. And therefore the as placed in the text for the proof does not signify pure likeness; but rather the assimilation of the proper exemplatum to its proper exemplar, etc.

Second, that the things placed in the middle of the text are so disposed that this doctrine comprehends under itself both, namely the speculative and the practical, because being one it extends itself to all. And this because it considers all things under one formal ratio. And this because it is a proper imitation of the science by which God knows Himself and other things, etc.

The third is concerning the phrase Whence, although in the sciences. For another argument can be drawn to prove the same consequence. For he intends that, because if affirmation is the cause of affirmation, negation will be the cause of negation, and conversely, as is said in I Poster.⁴; since from the antecedent there is had the unity of formal being (ens) in theology, with a diversity of physical formal beings of the sciences; and it is established that the diversity of formal beings diversifies the physical sciences into speculative and practical: it follows that from the non-diversity, or unity, of the formal being of theology, it itself will be one, at once containing the speculative and the practical.

VI. The second conclusion is⁵: Theology is more speculative than practical. – It is proved in two ways. First, it deals more principally with divine things than with human acts: therefore it is more speculative. – Second, thus: It deals with human acts on account of the contemplation of God: therefore it is more speculative. The antecedent is proved: because eternal beatitude consists in contemplation.

VII. Concerning the foregoing, two things must be noted⁶. The first is that this interpretation⁷ of the first conclusion is not fabricated or novel, but intimated in the body of the article; as is clear to one who diligently weighs what it means to say that a single existing being extends itself etc., and who considers that it speaks of specific unity, which it is established constitutes being one in itself. For by this it manifestly excludes the crude interpretation of those who understand theology to comprise within itself the practical and the speculative by way of aggregation. For then it would not be one except by aggregation: and not under one formal ratio, but under two: and properly speaking it would not comprehend both under itself, as the text says, but would be composed out of both. And to what purpose would the argument from the identity of God's knowledge, adduced in the text, have been brought forward?

And so that every such fantasy may be refuted, let them look at St. Thomas, IIa IIae, q. 45, art. 3, ad 1, where he expressly places infused wisdom in a higher order than the speculative and the practical, for the same reason he assumes here: namely, that the higher a reason is, the more things it extends to while remaining one. And another reason is adduced: namely, that this pertains to dignity. Since, therefore, this science is most worthy of dignity, as will be shown⁸; and has one common reason embracing all the practical and speculative sciences; and is of divine order: it is necessary that whoever interprets it otherwise than as a science of a higher order be wrapped in darkness as to both. – The same is also evident from the end of the preceding article: where it is expressly said that this doctrine has a proportion to the other sciences as the common sense has to the proper senses; and therefore it is not diversified by the differences of their objects, being of a higher order. And both reasons assigned here are touched upon: on the side of its higher formal reason, and on the side of its imitation of the divine science: since it is the proper impression and sealing of that science which is one and simple, not by aggregation, of all things.

VIII. Nor does the comparison adduced in the second conclusion stand in the way⁹. For together with being eminently both, it can be that something is formally both: just as the sun is eminently heating and drying, and yet also formally so; and God is eminently understanding, willing, and executing, and yet also formally so. Nor does that comparison intend anything else than that speculative science approaches more closely to the nature of theology than practical science does: just as if we were to say that common sense has more of the nature of sight than of hearing, the sense would be that the conditions of sight and of common sense agree more than do the conditions of hearing and of common sense. Nor is it otherwise in the matter at hand. – Nor, moreover, is it an obstacle that somewhere¹⁰ St. Thomas says that it is simply speculative, and practical in a certain respect. For the reason for what he says is this: because "speculative" signifies a more perfect difference of science, while "practical" signifies a less perfect one; and the conditions of the speculative suit so excellent a science more than do the conditions of the practical. It is therefore called speculative simply, that is, without any addition, because it is formally speculative, though eminently so. But it is called practical in a certain respect, and not absolutely, lest it be understood that it is an imperfect science, such as those are which are called practical absolutely.

Nor does it matter for our purpose whether the habit of theology, and universally of science, is held to be one on account of the simplicity of the quality, or one on account of the unity of the order of intelligible species. For in either way it must be that the order or quality of a higher grade than the order or quality constituting speculative science as distinct from practical science, and conversely.

IX. From¹¹ this position it is clearly evident that neither from the fact that the conditions of speculative science, nor from the fact that the conditions of practical science, belong to this science can it be inferred, therefore theology is speculative, or, therefore it is practical, as one is distinguished against the other; but rather, therefore it is speculative, or eminently contains the character of the speculative; and likewise, therefore it is practical, or eminently contains the character of the practical; and likewise, therefore it is affective, or eminently contains the character of the affective. Hence Scotus's arguments in the Prologue, question IV, from the definition of practical science and from the object of this science (namely, because from it are taken the principles that regulate practice, and the like), do not conclude that it is practical; but if they have any force, they conclude, as has been said, that it is practical, or that it eminently contains the character of the practical. – And therefore, you who devote yourselves to disputation, make use both of this reply and of that distinction concerning precisely and not precisely such, for example, the rule of the work or of contemplation, etc. For what is precisely such is either practical or speculative; but what is such, yet not precisely, is something higher, as is clear from what has been said.

Following this, there remains the special question concerning practice and the practical, which is to be treated separately.