Perceptual Fallacies

Our normal perceptions do not correspond directly to reality. The things that we percieve (see, hear, smell etc.) are not entirely determined by what our senses detect. Our perceptions are also determined by what we expect, what we know, what we believe.

Perceptual Constancies

Our tendency to have perceptual experiences in the absence of stimuli


We perceive what we expect to perceive

Looking for Clarity in Vagueness

When our senses are confronted with a formless stimulus, we often perceive something distinct. We look at clouds, smoke, fuzzy paintings and see shapes that are familiar. This illusion is called pareidolia. Many cases of pareidolia are common:


Our memories are consturctive, not literal

Imagine a scene...How do you look at it? Recall a scene - do you look at it through your own eyes?

Car accident film - hit vs. smash and long term memory - if people watch a car accident on film and are asked a question after viewing the scene, the wording of the question affects how the subject remembers the scene. When asked "How fast were the cars going when they smashed?", subjects reported faster speeds when asked about it again later than subjects who were asked, "How fast were the cars going when they hit?"

Selective memory - Dreams, we have over 250 a night but only remember a few of them.


We can lead ourselves to believe that something is paranormal or supernatural when it actually isn't.

Have you ever had a friend call just when you were thinking about them? It may seem strange or paranormal, but there are many more times when you think about someone or something and nothing related happens.

What are the chances that 2 people out of a party of 23 have the same birthday? 1/2-----1/1000-----1/40----- 1/2020

(the answer, surprisingly, is 1 in 2!)
How many things happen to you in the course of a day? Incredible pairings are more likely than you think.

Science is a systematic attempt to get around these limitations. Science tries to remove personal experience from the scientific process.

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Additional Resources

"Shrine of the Miracle Tortilla"

"Blondlot and N-Rays"