FallaciesPresumption
False Dilemma
Also called False dichotomy · Either/or fallacy · Black-and-white thinking
Presenting two options as the only possibilities when there are more.
Definition
A false dilemma forces a choice between two options by hiding the others.
Usually one option is made to look terrible, so the listener feels pushed into the other. The argument can be valid on paper: if it really is A or B, and A is bad, then B. The problem is the first premise, which assumes there are only two choices.
Form
- Either A or B.
- Not A.
- Therefore B.
This shape is valid. The fallacy is in premise 1, when C, D, or “some of both” were possible all along.
How to spot it
“You’re either with us or against us.”
“If we don’t do X, then Y” with no account of the other ways to prevent Y.
One option is described as a disaster and the other as the only alternative.
Middle positions, mixed approaches, or “neither” are never mentioned.
The choice comes with time pressure: “We have to decide now.”
Examples
01“Either we cut the school arts budget or we raise property taxes”
A school board frames its budget gap this way.
What went wrong
Other options are left off the list: trimming administrative costs, delaying a capital project, seeking a state grant, or combining smaller changes. Each may or may not work, but shrinking the menu to two decides the outcome before the debate starts.
02“If you don’t support this bill, you don’t care about safety”
A supporter frames opposition to one specific bill as opposition to safety itself.
What went wrong
Someone can care a great deal about safety and still think this bill is badly designed, or prefer a different one. The framing turns a question about policy design into a question about loyalty.
03“Trust the science or you’re a denier”
Someone asking a specific question about how a study was designed gets sorted into one of two camps.
What went wrong
You can accept a scientific consensus and still question a particular paper. Science depends on exactly that kind of questioning. Collapsing every question into “believer or denier” discourages the scrutiny that makes the consensus trustworthy.
Why it persuades
Two options are easy to think about, and five are tiring. A binary choice also makes the speaker sound decisive and anyone who hesitates sound weak. When one option is vivid and frightening, people stop looking for a third.
How to counter it
1Name the missing options
Don’t pick either side. Name one or two alternatives that weren’t on the list.
Are those really the only two choices? What about [option C], or some combination?
2Ask what rules out the middle
Make the speaker defend the claim that there are only two options. Sometimes they can, and that’s useful to know too.
What makes you think there’s nothing in between? What rules out a mix of both?
3Pull apart identity from the position
When the dilemma is about loyalty (“with us or against us”), separate the value from the specific proposal.
I share the goal. I’m questioning whether this particular plan is the best way to reach it.
When it's not a fallacy
Some choices really are binary. A switch is on or off, a defendant is convicted or acquitted, and a ballot measure passes or fails. A decision can also have only two realistic options once you account for time, money, or law. In those cases, saying “it’s A or B” is accurate.
The fallacy is in claiming there are only two options without showing why. If the speaker can explain what rules out the alternatives, it’s a real dilemma.
Sources & further reading
- Christopher Tindale, Fallacies and Argument Appraisal (Cambridge University Press, 2007).
- Bradley Dowden, “Fallacies”, Internet Encyclopedia of Philosophy.
- Hans Hansen, “Fallacies”, Stanford Encyclopedia of Philosophy.
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