Basics of Scholastic Disputation

Note: This is an ongoing project as I gather more resources on this topic, in this, I have synthesized four: Notes on Epistemology by Fr. John J. Toohey, S.J.; Tractus de Signis by John of St. Thomas; God and Reason by William Joseph Brosnan; and, Barbara Celarent by Thomas Gilby

To learn logic, check out my course of logic that provides a catechism on logic, video lessons, and a reading plan of Fr. Coppen's "Brief Text-Book on Logic."

Also, see the two videos I recorded explaining this article, Video 1, Video 2.

When engaging in proving a thesis, objections to that thesis ought to be answered. For ease of answering, one ought to put the objection in the form of a syllogism. A syllogism has four parts, a major premise, a minor premise, a consequence, and a consequent. The major, minor, and consequent are labeled “propositions,” and the consequence a “illation.”

Propositions are said to have three parts, the major term, middle term, and minor term. The major term is the predicate of the consequent (in our example below, mortal). The middle term is the term shared by the major and minor premise (in our example below, man/men). The minor term is the subject of the consequent (in our example below, Socrates).

An example follows:

Major Premise: All men are mortal.

Minor Premise: Socrates is a man

Consequence: THEREFORE,

Consequent: Socrates is mortal.

Further, these objections can take a second form, that of an “enthymeme.” This only has three parts, the antecedent, consequent, and consequence. The antecedent takes the place of the Major/Minor above, and one of them is said to be “hidden” or “assumed” (in our example below, the idea that “all men are mortal” is assumed). As above, the antecedent and consequent are labeled “propositions,” and the consequent an “illation.”

An example follows:

Antecedent: Socrates is a man

Consequence: THEREFORE,

Consequent: Socrates is mortal.

Now that one has formed the objection in the form of a syllogism or enthymeme, there must be two considerations. One may either treat the propositions, or the illation. Regarding the propositions, the response may be of three kinds.

First, the premise can be granted (i.e., affirmed to be true).

E.g., I am arguing that Socrates is not mortal. The argument is given: Socrates is a man, therefore, Socrates is mortal. I would respond “I concede the antecedent” and go on my way, having lost the argument.

Second, the premise can be denied (i.e., affirmed to be false).

Furthering the above example, let’s say the syllogistic form of this argument is given: All men are mortal, Socrates is a man, therefore, Socrates is mortal. If I want to continue the argument, I could say, “I deny the Major Premise,” and “I concede the minor premise” thus continuing the argument. From here, the argument would shift to the debate over whether all men are mortal, but there is something clearer I can do, i.e., I can distinguish.

Third, the premise can be distinguished (i.e., affirmed to be doubtful or equivocal, and can be taken in more than one sense), denying it in one sense, and affirming it in another sense.

Furthering the above example, a better way of continuing the argument in an orderly manner would be to employ a distinction. I could say “I distinguish the Major Premise, the body, I concede, the soul, I deny.” The advantage from here is that, at this point, the two may come to an agreement (both may agree that Socrates is mortal according to the body, and not mortal according to the soul), or a further objection can be given that is more restricted in its application (i.e., objecting to the thesis that Socrates is mortal merely according to the body)

A premise can be distinguished in four ways. First, when the middle term may be taken in two senses. In this case, both the major and the minor premise need to be distinguished.

For this example, we may take the argument against Sacred Scripture: “Adam was told that he would surely die on that day, Adam did not die on that day, therefore, a contradiction occurs.” Here, there is an equivocation which occurs with the term “die,” therefore I may respond, “I distinguish the major, spiritually die, I concede, physically die, I deny.” Further, “I contradistinguish the minor premise, physically die, I concede, spiritually die, I deny.”

More properly speaking, when there is an equivocation in the middle term of the minor premise we are said to contradistinguish the minor premise, affirmed when combined with the major premise in one sense, yet denied when combined with the major premise in another sense.

Shifting to another argument, let’s consider an argument against the freedom of the will: Predetermined acts are not free, Human acts are predetermined, therefore, Human acts are not free. Here, the issue is found with the term “predetermined” in that it is equivocated in the two uses. To the major I would respond, “I distinguish the major premise, predetermined by the secondary cause, I concede, by the first cause, I deny.” To the minor premise I would respond, “I contradistinguish the minor premise, predetermined by the first cause, I grant, by the second cause, I deny.” In this, the objector has made a fatal flaw, in the major premise, the predetermination is by the first cause (God), whereas in the minor premise, he argues that the predetermination is by the second cause, which is denied. Thus, equivocation occurs.

Second, when the major term can be taken in two senses, the major premise and conclusion are distinguished.

For this one, let’s think of an argument given by Muslim and Jewish philosophers (and Nestorious) against the incarnation: God cannot die, Jesus died, therefore, Jesus is not God. The issue here is with the term “God.” To respond, I could say, “I distinguish the major premise, according to nature, I concede, according to hypostasis, I deny.” Further, to explain the conclusion, I would say, “To the conclusion, I distinguish, Jesus is not God in any sense, I deny, Jesus is not merely God, I subdistinguish, naturally (qua natura), I concede, hypostatically, I deny.”

Third, when the minor term is taken in two senses, the minor premise and the conclusion are distinguished.

Fourth, when distinguishing the major/minor premise, it is sometimes necessary to make another distinction of the same premise, and in this we subdistinguish.

Going back to our objection against the Divinity of Our Lord, the response to the major premise is left wanting. For, we have distinguished between “nature” and “hypostasis,” but, here, we are left open to attack, for, are the hypostases of the Father and Spirit said to die? No. Therefore, we can expand the respond thus: “I distinguish the major premise, die according to nature, I concede, according to hypostasis, I subdistinguish, the hypostasis of the Son, I affirm, the hypostasis of the Father and Spirit, I subdistinguish, the ability to die if incarnate, I affirm, the actuality of hypothetical, I deny.” As you see, subdistinctions can be on multiple levels, clarifying the thesis.

Another move that can be done is that, if the premise doesn’t matter for the conclusion, he can “let it pass” (transmit).

For example, most meme arguments can be treated in this way, such as: People believe in the Flying Spaghetti Monster, therefore, God does not exist. To this I would respond, “I transmit the antecedent.”

Further, in an enthymeme, there is always something assumed by the proposition, which can be denied.

If someone wanted to seriously deal with the objection above, one could deny what is assumed in the antecedent, i.e., that the assertion of other “gods” does not disprove the existence of God.

Regarding the illation (consequence), it can be either valid or invalid, depending on whether a logical fallacy has occurred or not.

An example of this would be the syllogism: blue is a color, Socrates is a man, therefore, Protestantism is wrong. While the major, minor, and consequent are to be conceded, the consequence is invalid and therefore one would respond that “I deny the consequence.”

One must NEVER distinguish the consequence, one can only distinguish the consequent. The consequent is denied explicitly only when the previous premises are distinguished, for, when one or both of the previous premises are denied, then implicitly, the conclusion is denied.

Applying these categories, one ought to proceed in order, treating each one of the premises and stating their truth, falsity, or equivocation.