Extrasensory perception, or ESP, is the claimed ability to acquire information without using the known sensory channels. The category usually includes telepathy (mind-to-mind communication), clairvoyance (perception of distant or hidden objects), and precognition (knowledge of future events).

Laboratory tests of ESP have a long and controversial history. Early card-guessing experiments produced occasional positive results that later proved difficult to replicate under tighter controls. Meta-analyses of the best-controlled studies have yielded small effects that critics attribute to residual methodological flaws, selective reporting, or chance. No mechanism consistent with established physics has been demonstrated, and the effect sizes, when claimed, remain tiny.

Belief in ESP remains widespread in the general public. Anecdotes of seemingly inexplicable knowledge are common, yet they are also readily explained by coincidence, subtle sensory cues, memory biases, and the human tendency to find patterns. Scientific consensus holds that the evidence does not support the existence of extrasensory perception.

Extraordinary claims require extraordinary evidence. For ESP, that evidence has not yet met the standard.