What Is… the Illusion of Causality

Illusions of causality -example of a contingency table with null contingency

In this series, I dig a little deeper into the meaning of psychology-related terms. This week’s term is the illusion of causality.

The illusion of causality is a cognitive bias that makes us see causal relationships between things that aren’t actually related. This often comes into play in superstitions and pseudoscience. We naturally look for causal connections in the world around us, but our intuitive assessment of such connections isn’t always reliable. Our tendency to find these connections is so strong that we’re likely to see them even when it’s logically clear that there is no mechanism that a cause and effect relationship could be based on.

The illusion of causality isn’t dependent on intelligence or personality; it’s a natural consequence of how our brains work. A more extreme version of this may play a role in psychosis, which often involves abnormal perceptions of cause and effect relationships.

The scientific method is an approach that helps to compensate for the illusion of causality and other cognitive biases. Even most research methods can’t establish cause-and-effect relationships. They may establish correlations, but correlation alone does not imply causation.


When we estimate causality, we evaluate several things:

  • The priority principle: Does the potential cause precede the outcome?
  • The contiguity principle: Do the potential cause and outcome occur close to each other in time and space?
  • The contingency principle: Does the rate at which the outcome is present vary depending on whether the potential cause is present or absent?

A contingency table, shown below, represents how potential cause A and outcome B may relate to one another.

Outcome B presentOutcome B absent
Potential cause A present80%20%
Potential cause A absent80%20%

In the contingency table above, outcome B is not contingent on potential cause A, because the presence or absence of A makes no difference in whether outcome B is present. Outcome B is present 80% of the time, and potential cause A does sweet fuck-all to change that. This is known as a null contingency (although I kind of like sweet fuck-all contingency).

The illusion of causality happens when it looks to us like outcome B is contingent on the presence of potential cause A, when in fact it’s not.

The illusion of causality is stronger the more commonly the potential cause is present. It’s also stronger the more commonly the outcome occurs. So, in the example above where outcome B is present 80% of the time, our brains are more likely to do a cause-and-effect happy dance.

Jumping to conclusions

Research published in the journal Nature showed a link between illusions of causality and the tendency to jump to conclusions.

Previous research has shown that people who tend to have paranormal beliefs or superstitions are more vulnerable to causal illusions, and they also have a tendency to jump to conclusions.

Alternative health approaches

The popularity of alternative health approaches is often supported by illusions of causality. Homeopathy, for example, isn’t supported by scientific evidence plus it’s all kinds of out there when you explore how proponents of this pseudoscience say it works. However, if someone takes a homeopathic remedy and later starts to feel better, that can look as if it’s a cause-and-effect relationship even when it’s not.

In a paper in the journal Psychology & Health, Macfarlane and colleagues used the term “irrational health behaviours” to describe the use of alternative health remedies that fly in the face of what science shows about the remedies being either unhelpful or actually harmful. They pointed out that there can be high costs in terms of both money spent on the alternative treatments themselves and costs resulting from delays in getting evidence-based treatment. In the study they conducted, they found that presenting people with full contingency table information (in a simple form) decreased their willingness to pay for multivitamin supplements.

More pseudoscience

The illusion of causality also comes into play with other kinds of pseudoscience, like astrology. Let’s take the idea that Mercury in retrograde (an optical illusion) disturbs communication on earth (the Roman Mercury was based on the Greek god Hermes, who served as a messenger for other gods).

Things go wrong in terms of communication all the time, meaning the identified outcome is frequently present. The optical illusion of Mercury in retrograde is also pretty frequently present, happening for about 3 weeks, 3-4 times per year. Even with null contingency between the two, the frequent occurrence of both the identified potential cause and the outcome both promote the illusion of causality.

The effect of thinking in a foreign language

The language in which information is presented can affect a number of cognitive biases; this has been termed the foreign language effect. When people are performing tasks in a language other than their native language, they’re actually less prone to illusions of causality. This may relate to greater psychological or emotional distance from the problem, and greater abstraction or decreased emotional resonance may make it easier to evaluate contingencies.

Another possibility is that having information presented in a foreign language decreases processing fluency, which may lead to a more deliberate and analytical manner of processing of information rather than an intuitive manner.

Managing illusions of causality

Humans are prone to the illusion of causality; it’s just the way our brains work. Avoiding it isn’t possible, but it can be useful to recognize that it does exist and that science offers ways to gather data to counter those illusions. I think one of the downsides of the anti-science bias that seems to be fairly common these days is that it’s likely to strengthen people’s beliefs in causal illusions. Having a scientific background doesn’t stop the illusion of causality, but it can serve as a reminder to look for more objective information.

Do causal illusions sound like something that you may be seeing when you interpret the world around you?


  • Díaz-Lago, M., & Matute, H. (2019). Thinking in a Foreign language reduces the causality bias. Quarterly Journal of Experimental Psychology72(1), 41-51.
  • MacFarlane, D., Hurlstone, M. J., & Ecker, U. K. (2018). Reducing demand for ineffective health remedies: Overcoming the illusion of causality. Psychology & Health33(12), 1472-1489.
  • Matute, H., Blanco, F., Yarritu, I., Díaz-Lago, M., Vadillo, M. A., & Barberia, I. (2015). Illusions of causality: how they bias our everyday thinking and how they could be reduced. Frontiers in Psychology6, 888.
  • Moreno-Fernández, M. M., Blanco, F., & Matute, H. (2021). The tendency to stop collecting information is linked to illusions of causality. Scientific Reports11(1), 1-15.
The Psychology Corner: Insights into psychology and psychological tests

The Psychology Corner has an overview of terms covered in the What Is… series, along with a collection of scientifically validated psychological tests.

Ashley L. Peterson headshot

Ashley L. Peterson


Ashley is a former mental health nurse and pharmacist and the author of four books.

22 thoughts on “What Is… the Illusion of Causality”

  1. Well written, Ashley. This is how conspiracy theories gain traction…implying causation with insufficient evidence.
    I saw a funny image the other day depicting this very idea. It was a seagull sitting on a long metal railing. The part of the railing that it rested on was severely bent downward. A simple and perfect image to illustrate correlation is not causation.

  2. Actually, the last post was on the relationship between red hair color and pain tolerance. There’s a gene mutation that causes both. The fact that red-haired people tend to be more tolerant of pain is true, but hair color is a result, not a cause.

  3. We got sick ostensibly from something we ate and our digestion was fucked up for more than a month. We tried elimination of foods to pinpoint a source. We thought we found one and our tummy slowly got better.

    Then it went berserk again. We had eaten the offending food class but we eat enough different kinds of foods that the illusion of causality is likely in play.

    Stress is as likely a cause as a kind of food—but they’re all present 😡 each day.

    So it’s hard to find our true causation without a really rigorous approach and possibly medical help.

    We aren’t usually looking for causation in life unless it’s major quality of life issues. Like, we don’t care who left the milk out all night; the milk is spoiled and we can send an fyi to our family to try to remember to put the milk away. Everyone makes mistakes and we aren’t benefiting from blaming or even holding someone accountable for a minor mistake. Not worth the energy for us. We’re not mad

    But figuring out how to not sit on the toilet an extra 5 times per day shitting our guts out seems worth finding causation lol

  4. Do causal illusions sound like something that you may be seeing when you interpret the world around you?
    Only in the case of my BPD. From what I’ve read about BPD, causal illusions are part of the disorder. I am very aware that I have ‘mistaken thinking’ sometimes, and I’ve worked hard to stop jumping to conclusions about things. I used to be very prone to it.

    This is one big reason I dislike socializing very much. I’m aware (which might be a causal illusion actually) but I’m aware that how I see the world and situations isn’t necessarily the same way the majority of others will see the world or situations.

    It’s made me a little paranoid actually. I have never bought into blatant illusions though, I’m skeptical of most things and have learned to research and back up with reliable source facts if I’m spouting off about something that is questionable.

    Like the whole Covid vaccines cause mutations in humans b.s. I state facts about what I know about the vaccines or Covid in general. And yet, there are still those who dismiss my point of view, even though it’s backed up with information from the CDC or reliable medical/scientific journal information.

  5. I’ve been trying to make a comment here for several days, and I keep failing to word it coherently. So here goes (just be forewarned).

    I think I actually do this a lot, and I suspect most people do it a lot as well. I think that when we begin to correlate two events taking place within a single temporal framework, it is natural to think that one of them is the cause of the other. If it even slightly precedes the other event, we tend to jump to the conclusion that it was the “cause.”

    I also think that when we think one event is the cause of another, it is sometimes the case that the two events may be completely unrelated. and their temporal coinciding with each other is totally random. At other times, especially when I see the connection frequently, I think that there may be a cause concealed deeper down the chain of events somewhere, something that “caused” both events to take place. But even in this case, neither event is the cause of the other.

    On a related note, people have a way of saying that two events are “synchonicitous” implying that there is some connection without either being the cause of the other. I don’t use that language too much, but maybe you have some insights on that. Okay, hope this made sense.

    1. I agree, this probably happens a lot for most people.

      I’ve never been entirely sure what synchronicity referred to beyond meaningful coincidences. It was something Carl Jung came up, and it sounds like he thought it was the universe giving people a sign by connecting their thoughts with what’s happening in the outside world.

      1. I had been thinking maybe “synchronicity” described what I was trying to describe in the previous (third) paragraph. The situation where something unseen is causing each of two events to occur simultaneously, but neither is the cause of the other. Apparently, Jung was not on that wavelength.

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