Inference by Added Determinants

Three: the determinant changes the reference. "Alleged", "former", "counterfeit", "putative" do not narrow a class; they take you outside it.

"A note is money" does not give "a counterfeit note is counterfeit money", and more importantly it does not give that a counterfeit note is money at all. "A director is an officer of the company" does not give "a de facto director is a de facto officer" without a great deal more argument, and "a will is a testamentary instrument" does not give "an alleged will is an alleged testamentary instrument" in any useful sense, since an alleged will may be no will at all.

Determinants of this kind are sometimes called alienans determinants, because they alienate the term from its class rather than qualifying it.

Why the failures happen

Because the inference assumes something it never states: that the determinant is doing the same work in both places.

Stated fully, the argument is an enthymeme. "A horse is an animal; 'white' means the same applied to a horse and to an animal; therefore a white horse is a white animal." The middle premise is what makes it work and it is exactly what is missing when the inference fails.

So added determinants is a valid immediate inference only for a restricted class of determinants, and the restriction is a matter of the words used, which makes it, like material obversion, only partly formal. That is a fair thing to say in an answer and it distinguishes a good one.

Where a lawyer meets it

In statutory construction, whenever a section qualifies a defined term. An Act defines "workman" and then, in a later section, speaks of a "casual workman" or a "contract workman". Does the qualified expression still fall within the definition? Sometimes it does and sometimes the qualification takes it outside, and the question is exactly the one this chapter is about.

In pleading a qualified allegation. "The defendant is a partner" and "the defendant is a dormant partner" are different allegations with different consequences, and the second does not follow from the first with the determinant carried across.

In the standard of care. "A doctor is a professional" does not yield "an inexperienced doctor is an inexperienced professional" with any useful content, and the law's answer is that the standard is the same however inexperienced the doctor is. That answer is a legal rule, and it exists precisely because the inference by added determinants would otherwise be tempting.

A worked example

A section provides: "Every director is liable to account for secret profits."

Add a determinant. Suppose it is argued: "every director is liable to account for secret profits; therefore every nominee director is liable to account for nominee secret profits."

Test it. "Nominee" applied to a director means a director appointed to represent another's interest. Applied to a profit it means nothing at all: profits are not nominees. The determinant is not univocal across the two terms, and the conclusion is not merely false but meaningless.

Now a determinant that does work. "Every director is liable to account for secret profits; therefore every former director is liable to account for former secret profits." Here "former" applies intelligibly to both, and the conclusion is still wrong, because "former secret profits" is not a class the section speaks about: profits made in the past do not stop being profits, so the determinant has changed the reference of the predicate while merely narrowing the subject. This is failure three.

What the section actually yields. By the ordinary rules, an A proposition about directors and liability. Whether it reaches a former director is a question of construction, to be answered by asking whether the liability attaches at the time of the profit or at the time of the claim. No inference by added determinants answers it, and the value of the topic is that it shows why: the qualification has to be argued about, not carried across.

Distinctions that carry marks

What this does not mean

The inference is not always invalid. With an absolute, univocal determinant it is perfectly sound, and it is used constantly without anybody noticing.

"Small" is not a vague word here, it is a relative one. The objection is not that its boundary is fuzzy but that its standard is drawn from the class it qualifies, so it means two different things in the two places.

An alienans determinant is not a narrow qualification. It does not pick out a part of the class; it takes the term outside the class altogether, which is why a counterfeit note is not a kind of money.

Quick revision

Form: add the same determinant to subject and predicate, leaving quality and quantity alone.

Valid when the determinant is absolute and univocal, meaning the same applied to both terms.

Three failures: relative determinants, whose standard shifts with the class; evaluative determinants, whose standard comes from a purpose; and alienans determinants, which take the term outside its class.

Classical example of failure: an elephant is an animal, but a small elephant is not a small animal.

Legal example of failure: a surgeon is a man, but a good surgeon is not thereby a good man.

It is an enthymeme: the suppressed premise is that the determinant does the same work in both places.

Test yourself

1. Define inference by added determinants and give a valid example.

It is the immediate inference in which the same qualifying term is attached to both the subject and the predicate of a proposition, the quantity and quality being unchanged. A valid example is "a judge is a public servant, therefore a retired judge is a retired public servant", where "retired" means the same withdrawal from office whether applied to a judge or to a public servant.

2. State the condition on which the inference depends.

That the determinant is absolute and univocal, meaning that it has a fixed sense which does not change according to the class it qualifies. Where the determinant means one thing applied to the subject and another applied to the predicate, the inference fails, because the two terms in the conclusion are not qualified in the same way and the conclusion is therefore not what the premise supports.

3. Give the classical failure and explain it.

"An elephant is an animal, therefore a small elephant is a small animal" is false, since a small elephant is a very large animal. "Small" is a relative term: it means small for an elephant when applied to an elephant and small for an animal when applied to an animal, and those are entirely different standards. Every comparative word behaves in the same way.

4. Why do evaluative determinants fail, and give a legal example.

Because an evaluative word takes its standard from a purpose, and the purpose changes with the class. "A surgeon is a man, therefore a good surgeon is a good man" fails because being good as a surgeon is skill in surgery while being good as a man is something else. In law, "an advocate is an agent" does not yield "a diligent advocate is a diligent agent", since diligence in an advocate is measured against professional standards and in an agent against the ordinary duty of an agent.

5. What is an alienans determinant?

One that does not narrow a class but takes the term outside it. "Counterfeit", "alleged", "former" and "putative" are of this kind: a counterfeit note is not a kind of note in the sense that matters, and an alleged will may be no will at all. Attaching such a determinant to both terms produces a conclusion about something that is not a member of either original class.

6. Why is this inference described as an enthymeme?

Because it rests on a premise it never states: that the determinant does the same work when attached to the subject as when attached to the predicate. Where that premise is true the inference is sound; where it is false the inference fails. Since the truth of the premise is a matter of what the words mean rather than of the form of the proposition, the inference is only partly formal, as material obversion also is.