Identifying an Argument

An argument asserts its premises and asserts its conclusion. A conditional asserts neither. That is the whole distinction, and it can be tested in one move: ask whether the speaker has committed themselves to anything being true. In a conditional they have not.

A conditional can of course be a part of an argument, and usually is. "If the notice was not served, the suit is premature. The notice was not served. Therefore the suit is premature." That is an argument with three statements, of which the first is a conditional serving as a premise.

The explanation trap

Compare two sentences, both containing "because".

A. "The suit was dismissed because it was filed after the period of limitation had expired."

B. "The suit must have been dismissed, because no execution proceedings were ever taken out."

They look identical in structure and they are doing completely different work. In A, everybody already accepts that the suit was dismissed; the sentence tells you why it happened. In B, nobody yet knows whether the suit was dismissed; the sentence gives a reason for believing that it was.

A is an explanation. B is an argument. The test is the one implicit in that comparison, and it is the standard test:

Is the statement in question already accepted as a fact? If it is, the passage is telling you the cause of it, and is an explanation. If it is in doubt, and the other statement is offered to remove the doubt, the passage is an argument.

The two are worth separating carefully, because law is full of both. A judgment that says "the accused was acquitted because the sole witness turned hostile" is explaining. A judgment that says "the witness must have been won over, because his statement in court contradicts his statement to the police in every material particular" is arguing.

Enthymemes: the argument with a piece missing

Real arguments almost never state everything. An enthymeme is an argument in which a premise, or occasionally the conclusion, is left unstated because it is thought too obvious to be worth saying.

"He is a partner in the firm, so he is liable for its debts."

The stated premise is that he is a partner. The stated conclusion is that he is liable. The unstated premise is the whole of the law being relied on: that every partner is liable for the debts of the firm. Supplying it is called completing the enthymeme, and it is the single most useful thing a law student can learn to do, for two reasons.

First, the suppressed premise is usually where the argument is weakest, precisely because nobody said it out loud. Second, in legal argument the suppressed premise is usually the proposition of law, and identifying it is identifying what the case is actually about.

There is a rule for supplying it. Supply the weakest premise that makes the argument work. If the missing premise can be stated modestly or sweepingly, choose the modest form, because attributing a sweeping claim to someone who did not make it is a way of losing an argument you should have won.

A worked example

Read this passage and decide what it is.

"The plaintiff has produced no receipt. In a suit for recovery of money lent, the burden of proving the loan lies on the plaintiff. Where a person who could easily produce the best evidence of a transaction does not produce it, a court may presume that it would not have helped him. The claim therefore deserves to be dismissed."

Is anything offered in support of anything? Yes, plainly. The last sentence carries the indicator "therefore".

Is it an explanation? No. It is not telling us why the claim was dismissed, as a known past event. It is urging that it ought to be dismissed, which is in doubt.

Are there any conditionals? The third sentence has the shape of one but is in fact a general rule, asserted. It is a premise.

Any enthymeme? Yes, and finding it is the point of the exercise. The argument moves from "no receipt was produced" to "the claim deserves to be dismissed", and the step is missing that a receipt is the best evidence of a money loan and could easily have been produced. Without that step the third premise does not connect to the first at all. Once supplied, the weakness is visible: whether a receipt could easily have been produced is a question of fact that this passage never establishes.

That is what identification is for. The passage looked like four confident sentences. Setting it out showed that it stands on an assumption nobody stated.

Distinctions that carry marks

What this does not mean

"Because" does not mark an argument. It marks a reason, and reasons come in two kinds: reasons why something happened and reasons for believing something is so. Only the second makes an argument.

A passage without indicator words may still be an argument. Legal writing frequently omits them entirely and relies on the reader to see the structure.

An enthymeme is not a defective argument. It is the ordinary form of argument in speech and in writing. Only the completed version can be assessed, which is why completing it is a step and not a criticism.

Quick revision

The test: is any statement offered as evidence or reason for accepting another? If not, no argument.

Not arguments: reports, descriptions, illustrations, statements of opinion standing alone, loosely associated statements, warnings, advice, conditionals, explanations.

Conditional: asserts neither its antecedent nor its consequent, so it cannot be an argument by itself, though it can be a premise.

Explanation against argument: is the statement already accepted, or in doubt? Accepted means explanation.

Enthymeme: an argument with a premise or conclusion left unstated. Complete it before assessing it, and supply the weakest premise that makes it work.

Test yourself

1. State the test for whether a passage contains an argument.

Ask whether any statement in the passage is being offered as evidence or as a reason for accepting another statement, that is, whether there is an inferential claim. If there is, the passage is an argument, however badly expressed. If nothing supports anything, the passage is not an argument, however long, learned or persuasive it may be.

2. Distinguish an argument from an explanation and give one example of each.

In an argument the statement in question is in doubt and the other statements are offered as grounds for believing it. In an explanation the statement is already accepted and the other statements give its cause. "The decree must be a nullity, since the court had no pecuniary jurisdiction" is an argument. "The decree was set aside because the court had no pecuniary jurisdiction" is an explanation of something already known to have happened.

3. Why is a conditional statement not an argument?

Because it asserts neither of its two component statements. An argument puts its premises forward as true and claims its conclusion is true; a conditional claims only that the one would follow from the other, and commits the speaker to nothing about whether either is actually so. It can, however, serve as a premise in an argument, and in legal reasoning it usually does.

4. Complete this enthymeme and identify the suppressed premise: "The agreement was made with a minor, so it is void."

1. An agreement with a person who is not competent to contract is void.

2. A minor is not competent to contract.

3. The agreement was made with a minor.

Therefore the agreement is void.

The suppressed material is the whole of the law relied on, statements 1 and 2, which is the usual position: what is left unsaid in a legal enthymeme is the legal proposition, and that is exactly what the case turns on.

5. Is the following an argument? "Trespass to land is actionable without proof of damage. So is libel. So is assault."

No. It is an illustration. The three sentences do not support one another; the second and third are further examples of the same kind of tort, offered to make the class clear rather than to establish that any of them is actionable without damage. Nothing is in doubt and nothing is being proved.

6. What rule governs the supplying of a missing premise?

Supply the weakest premise that makes the argument work. A missing premise can usually be stated either modestly or sweepingly, and only the modest version is a fair reconstruction of what the speaker meant. Attributing an extravagant claim to an opponent in order to refute it easily is itself a fault of reasoning, and one that a court will notice.