false assumption

Meanings

1. 1phrasecountable

   A belief that you accept as true without checking, but which is actually wrong.

   Grammar: Countable: you can say 'a false assumption' or 'false assumptions'; it often follows verbs like make, base something on, or challenge.

   Patterns

   • make a false assumption
   • base something on a false assumption
   • a false assumption about something
   • challenge a false assumption

   The whole plan failed because it was built on a false assumption about how much time we had.

   She made a false assumption that everyone in the room spoke English.

   Before you argue, check whether you are working from a false assumption.

2. 2phrasecountabletechnical

   In logic and statistics, a starting belief used in an argument or test that is later shown to be untrue.

   Grammar: Used as a countable noun in technical contexts; often appears after 'under' or 'based on'.

   Patterns

   • under a false assumption
   • test a false assumption
   • a false assumption in the model

   The study's results are unreliable because it began with a false assumption about the data.

   In logic, a false assumption can make a valid argument reach a wrong conclusion.

Word forms

Common combinations

make a false assumption

Try not to make a false assumption before you have all the facts.

base something on a false assumption

Their decision was based on a false assumption about the cost.

a false assumption about

He had a false assumption about what the job involved.

challenge a false assumption

Good teachers challenge false assumptions in the classroom.

work from a false assumption

If you work from a false assumption, your answer will be wrong.

Synonyms and how they differ

misconception

A misconception is a wrong idea that many people hold; a false assumption is often a personal belief used as a starting point in reasoning.

fallacy

A fallacy is a false belief or a flawed argument, often in formal logic; a false assumption is simply the untrue starting point.

misbelief

Misbelief is a less common word for a wrong belief; it does not emphasize the idea of taking something for granted.

Opposites

Word family

assume verb

To accept that something is true without proof.

assumption noun

A belief that you accept as true without checking.

assumed adjective

Accepted as true without proof.

Commonly confused: false assumption or false premise?

Practice

Make it your own

Write a sentence using “false assumption”, then check it and compare it with the examples above.

Explore more words