Does anyone know St Thomas Aquinas' definition of science?



In our RCIA program we were taught that there are two orders of knowledge - the supernatural and the natural.

Since God is author of both, “correct” knowledge in both orders must always be in harmony…isn’t this true?

Further, we were taught that any organized body of knowledge with first principles can legitimately be called a science. Hence, theology is also a science is it not?

Does anyone know St Thomas Aquinas’ definition of science?

Cheers and God bless,
Alpine Meadow


Aquinas defined science as "the knowledge of things from their causes", and yes, he considered theology a science. He also posited that "no demonstrated truth (science) was opposed to revealed truth (faith)."


Science and the Church

The words "science" and "Church" are here understood in the following sense: Science is not taken in the restricted meaning of natural sciences, but in the general one given to the word by Aristotle and St. Thomas Aquinas. Aristotle defines science as a sure and evident knowledge obtained from demonstrations. This is identical with St. Thomas's definition of science as the knowledge of things from their causes. In this sense science comprises the entire curriculum of university studies. Church, in connexion with science, theoretically means any Church that claims authority in matters of doctrine and teaching; practically, however, only the Catholic Church is in question, on account of her universality and her claim of power to exercise this authority. The relation between the two is here treated under the two heads SCIENCE and CHURCH.

Summa contra Gentiles Book 1, 94

[3] Again, if science is the knowledge of a thing through its cause, and if God knows the order of all causes and effects, and thereby knows the proper causes of singulars, as was shown above, it is manifest that in a proper sense there is science in Him. Nevertheless, this is not the science caused by ratiocination, as our science is caused by demonstration. Hence 1 Samuel (2:3): “For the Lord is the God of all knowledge.”

ScG B 1, 92

[3] Again, a habit is an imperfect act, as being intermediate between potency and act; hence, those possessing a habit are compared to those who are asleep. But in God there is most perfect act. Act, therefore, is not in Him as a habit, for example, science, but as the act of considering, which is an ultimate and perfect act.

[12] Likewise, “a habit is that by which one acts when he wills.” Therefore, a habit and the operation in keeping with it must exist in the same subject. Intellectual consideration, which is the act of the habit of science, cannot, however, be the function of the passive intellect, but belongs to the possible intellect itself; for a power must not be the act of a body if it is to be capable of understanding. Thus, the habit of science is not in the passive but in the possible intellect. Now, science is in us, and it is in accordance with this science that we are said to know scientifically. Therefore, the possible intellect also is in us, and has no being apart from us.

ScG B 2, 60[13] Scientific knowledge, moreover, consists in the assimilation of the knower to the thing known. Now, the knower is assimilated to the thing known, as such, only with respect to universal species; for such are the objects of science. Now, universal species cannot be in the passive intellect, since it is a power using an organ, but only in the possible intellect. Therefore, scientific knowledge cannot reside in the passive intellect, but only in the possible intellect.


Thank you for the informative posts!

Cheers and God bless,


[quote="Alpine_Meadow, post:4, topic:253389"]
Thank you for the informative posts!

Cheers and God bless,


Goood post!


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