10/07/2025
For a person who does not believe facts, several terms may apply, depending on the reason for their disbelief. The most appropriate word can range from psychological diagnoses like delusional to more general descriptors like "denialist" or "conspiracy theorist".
Common terms
Denialist: A person who rejects basic facts or reality, especially in favor of an alternate and more comfortable "truth". This can include rejecting well-established scientific or historical consensus, such as climate change or the Holocaust.
Delusional: A psychological term for someone who has a fixed, false belief that is resistant to change, even when presented with evidence to the contrary. In a clinical context, this is a symptom of a mental health condition. Colloquially, it can describe someone who holds unrealistic or irrational beliefs.
Conspiracy theorist: A person who believes that a harmful or tragic event was not the result of the accepted explanation, but was instead orchestrated by a secret, powerful group. This often involves rejecting facts in favor of a different, more complex narrative.
Ignorant: While not a psychological term, it describes someone who lacks knowledge or information. An ignorant person might not believe facts simply because they are unaware of them, not because they are willfully rejecting them.
Close-minded or Stubborn: These are more general, informal descriptions for someone who refuses to consider new information or perspectives that challenge their pre-existing beliefs.
Incredulous: Describes a person who is unwilling or unable to believe something. Unlike a skeptic, an incredulous person is so doubtful that they refuse to accept something at all.
A note on "skeptic"
While often associated with disbelief, a skeptic is technically a person who questions the validity or authenticity of something purporting to be factual until they see strong evidence. A skeptic's doubt is based on a thoughtful, evidence-based approach, while the other terms describe a person who continues to disbelieve even when presented with solid evidence.