excluded middle

noun

1. logic the principle that every proposition is either true or false, so that there is no third truth-value and no statements lack truth-value

Example Sentences

But there’s a disgraceful cynicism working in this “fallacy of the excluded middle.”

From Salon

In the face of such uncertainty, Dr. Schwitzgebel has advocated for what he calls “the design policy of the excluded middle.”

From New York Times

Once more I find myself stuck in the excluded middle and this time I'm thinking about Brouwer's Theorem.

From Salon

The law of the excluded middle is a technique of logical argumentation that most famously rears its head in "proofs by contradiction", wherein you show a statement is true by assuming otherwise and use this contrary assumption as a starting point of an argument that leads to a known mathematical falsehood, like 0=1.

From Salon

Among other things Brouwer was known for founding the intuitionist school of mathematics, a movement that declared that the only true mathematics was mathematics that was careful with its infinities and didn't prove theorems through the use of the law of the excluded middle.

From Salon