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brain-in-a-vat

/ˌbreɪn ɪn ə ˈvæt/
IELTSAcademic
noun

A philosophical idea that a brain could be kept alive in a container and fooled into having normal experiences. It is used to ask whether we can really know what is real.

  • The professor used the brain-in-a-vat idea in class.
  • Brain-in-a-vat arguments question reality itself.

Adinary Nuance

A brain-in-a-vat is not a real object you normally see in science or medicine. It is a thought experiment, so it is different from words like illusion, dream, or simulation, which describe experiences or systems more directly. Writers use it when they want to question whether our senses can be trusted. It sounds technical and academic, not everyday.

In other languages

Vietnamese
não trong bình
Spanish
cerebro en una cubeta
Chinese
缸中之脑
Japanese
水槽の中の脳
Korean
통 속의 뇌

Etymology

This phrase comes from modern philosophy and science fiction. It became well known in the late 20th century through debates about knowledge and reality.

Common phrases

brain-in-a-vat argumentbrain-in-a-vat scenariothe brain-in-a-vat problem

Synonyms

Related words

Frequently asked questions

Is brain-in-a-vat a common word in everyday English?
No. It is mostly used in philosophy, academic writing, and discussions about reality.
What is the difference between brain-in-a-vat and simulation?
A simulation is a made system or experience. A brain-in-a-vat is a philosophical thought experiment about being deceived.
Can I use brain-in-a-vat in business writing?
Usually no. It sounds academic and philosophical, not businesslike.
How do I use brain-in-a-vat in a sentence?
Use it when discussing knowledge, reality, or philosophy, not literal medicine.