Amphiboly

The police and the drinking

“The police were told to stop drinking on campus after midnight. So they should be much better at responding to emergencies now.”

The instruction almost certainly meant that the police should stop other people drinking on campus. Read that way, it says nothing about how alert the officers are. The conclusion only follows from the other reading, that the officers themselves had been drinking. This is a textbook case, used in the Stanford Encyclopedia of Philosophy’s entry on fallacies: the words are all clear, and the grammar is what leaves “who is drinking?” open.

Who got the job?

Morgan: Sam told Alex that he got the job.

Riley: Alex got the job? That’s great, I’ll send him a note.

“He” could refer to Sam or to Alex. Riley picks one and acts on it. Nothing in the sentence says which, and the other reading (Sam got the job and was telling Alex about it) is just as natural. This is the everyday form: a pronoun with more than one possible antecedent (the noun it refers back to), and a conclusion that quietly depends on choosing one.

The repair clause

A lease says: “The landlord will pay for repairs to appliances and plumbing over $200.” The dishwasher needs a $90 repair. The tenant says: “The lease says the landlord pays for appliance repairs, so this one is on you.” The landlord says: “The $200 limit applies to both, so it’s on you.”

The phrase “over $200” can attach to “plumbing” alone or to “appliances and plumbing” together. Each side quotes the clause as if it plainly supported them, when the grammar supports both readings. That makes this example harder to spot than the others: neither reading is absurd, and the sentence really was written by someone. Hurley and Watson single out contracts and wills as two areas where amphiboly causes serious problems.

Amphibolies come from different grammatical sources:

• Attachment: a modifier that could belong to more than one part of the sentence, as in the repair clause. The Stanford Encyclopedia’s entry on ambiguity gives “superfluous hair remover”: a remover that is superfluous, or a remover of superfluous hair.
• Pronoun reference: “he”, “it” or “they” with more than one candidate, as in the job example.
• Dangling modifier: a phrase with no clear subject. Hurley and Watson’s example has a tour guide say that “standing in Greenwich Village, the Empire State Building could easily be seen”, from which someone concludes that the building is in Greenwich Village.
• Punctuation: a missing or misplaced comma that changes the grouping. Hamblin (1970) recounts the sixteenth-century play Ralph Roister Doister, in which a love letter punctuated differently becomes a stream of insults.
• Scope and grouping: words like “and”, “or”, “all” and “not” that can group in more than one way. The best-known sentence of this kind is the wartime slogan “Save soap and waste paper”, cited by the logician Irving Copi: save (soap and waste paper), or (save soap) and (waste paper).

The name means “double arrangement”. It goes back to Aristotle’s Sophistical Refutations, which lists amphiboly among six ways an argument can mislead through language. His examples depend on Greek word order, such as a phrase translated “I wish that you the enemy may capture”, where it’s unclear who captures whom. Many older examples are ambiguous prophecies, such as the oracle said to have told King Pyrrhus, in a Latin sentence that works either way, that he could defeat the Romans, or that the Romans could defeat him.

Amphiboly vs. equivocation. Both are fallacies of ambiguity, but they differ in two ways that Hurley and Watson identify. In equivocation, one word or phrase shifts meaning (“the end of life is death; happiness is the end of life”, where “end” means first ceasing, then purpose). In amphiboly the words keep their meanings and the grammar is ambiguous. And an equivocation is usually the arguer’s own doing, while an amphiboly usually involves misreading a sentence someone else wrote. When that misreading is then attacked as the other person’s view, it overlaps with a Straw man.

An ambiguous sentence isn’t a fallacy by itself. It becomes one only when a conclusion rests on a reading that the sentence and its context don’t support.

• No inference is drawn. A clumsy headline, a joke that plays on both readings, or a slogan like “Save soap and waste paper” is ambiguous, but it isn’t an argument. Hamblin (1970) makes this point about the textbook examples, and reports that none he found showed anyone actually misled by an ambiguous construction into a conclusion.
• Context settles the reading. Grammatical ambiguity is common in ordinary speech, and people usually resolve it without thinking. Choosing the reading that context makes clear is ordinary understanding, not a fallacy.
• The ambiguity is noticed and argued out. Saying “this can be read two ways, and here’s why it should be read this way” is exactly the right response to an ambiguous sentence.
• Both readings lead to the same conclusion. If the conclusion follows either way, the ambiguity does no work.

The test: does the conclusion still follow on the other reading, and if not, what shows that this reading is the intended one?

Whipped to stiff peaks

A recipe says: “Fold the egg whites into the batter, whipped to stiff peaks.” A cook reasons: “It must mean the egg whites are whipped, since batter doesn’t form stiff peaks. So I’ll whip the whites first, then fold them in.”

The sentence is grammatically ambiguous: “whipped to stiff peaks” could attach to the whites or to the batter. The cook chooses a reading and acts on it, like the job example. The difference is that context settles the reading: only one of them describes something that can happen in a kitchen, and the cook says so.

Arguing over the repair clause

Back to the lease. The tenant writes: “The clause could be read either way, so I looked at the listing, which said ‘all appliance repairs covered by landlord’, and at your email from March, where you paid for a $120 washer repair without mentioning a limit. Both suggest the $200 threshold was only meant for plumbing.”

The tenant reaches the same conclusion as before, but no longer treats the clause as if it said so plainly. They notice the ambiguity and argue for one reading with evidence of what was meant. The argument may or may not win, but it doesn’t trade on the ambiguity; it addresses it.

Readers often resolve grammatical ambiguity quickly, without noticing that there was a choice. The first reading that comes to mind simply is what the sentence means, as far as the reader can tell, so it doesn’t occur to them to check the other one. That’s why an amphiboly can be committed in good faith.

When something is at stake, the reading that comes to mind first can also be the one that suits the reader, which makes the other reading even easier to miss. Ruiz (2018) notes that the ambiguities usually arise from mistakes in grammar, and that not all amphibolies are trivial: carelessly drafted contracts and wills have produced real and painful disputes.

• Say both readings out loud. Stating the other reading is often enough to show the conclusion depended on the choice.
• Ask whether the conclusion survives on the other reading. If it does, the ambiguity doesn’t matter.
• Look to context or ask the author. What else did they say, and what would make sense for them to have meant?
• When you’re writing, reword so that only one reading is possible: repeat the noun instead of using “he”, move modifiers next to what they modify, and add the comma.