You're not irrational, you're just quantum probabilistic: Researchers explain human decision-making with physics theory

September 14, 2015 by Pam Frost Gorder, The Ohio State University
Credit: Rice University

The next time someone accuses you of making an irrational decision, just explain that you're obeying the laws of quantum physics.

A new trend taking shape in not only uses to explain humans' (sometimes) paradoxical thinking, but may also help researchers resolve certain contradictions among the results of previous psychological studies.

According to Zheng Joyce Wang and others who try to model our decision-making processes mathematically, the equations and axioms that most closely match human behavior may be ones that are rooted in quantum physics.

"We have accumulated so many paradoxical findings in the field of cognition, and especially in decision-making," said Wang, who is an associate professor of communication and director of the Communication and Psychophysiology Lab at The Ohio State University.

"Whenever something comes up that isn't consistent with classical theories, we often label it as 'irrational.' But from the perspective of quantum cognition, some findings aren't irrational anymore. They're consistent with —and with how people really behave."

In two new review papers in academic journals, Wang and her colleagues spell out their new theoretical approach to psychology. One paper appears in Current Directions in Psychological Science, and the other in Trends in Cognitive Sciences.

Their work suggests that thinking in a quantum-like way—essentially not following a conventional approach based on classical probability theory—enables humans to make important decisions in the face of uncertainty, and lets us confront complex questions despite our limited mental resources.

When researchers try to study human behavior using only classical mathematical models of rationality, some aspects of do not compute. From the classical point of view, those behaviors seem irrational, Wang explained.

Wang on quantum cognition, Aug. 2014 

For instance, scientists have long known that the order in which questions are asked on a survey can change how people respond—an effect previously thought to be due to vaguely labeled effects, such as "carry-over effects" and "anchoring and adjustment," or noise in the data. Survey organizations normally change the order of questions between respondents, hoping to cancel out this effect. But in the Proceedings of the National Academy of Sciences last year, Wang and collaborators demonstrated that the effect can be precisely predicted and explained by a quantum-like aspect of people's behavior.

We usually think of quantum physics as describing the behavior of sub-atomic particles, not the behavior of people. But the idea is not so far-fetched, Wang said. She also emphasized that her research program neither assumes nor proposes that our brains are literally quantum computers. Other research groups are working on that idea; Wang and her collaborators are not focusing on the physical aspects of the brain, but rather on how abstract of quantum theory can shed light on human cognition and behaviors.

"In the social and behavioral sciences as a whole, we use probability models a lot," she said. "For example, we ask, what is the probability that a person will act a certain way or make a certain decision? Traditionally, those models are all based on classical probability theory—which arose from the classical physics of Newtonian systems. So it's really not so exotic for social scientists to think about quantum systems and their mathematical principles, too."

Quantum physics deals with ambiguity in the physical world. The state of a particular particle, the energy it contains, its location—all are uncertain and have to be calculated in terms of probabilities.

Quantum cognition is what happens when humans have to deal with ambiguity mentally. Sometimes we aren't certain about how we feel, or we feel ambiguous about which option to choose, or we have to make decisions based on limited information.

"Our brain can't store everything. We don't always have clear attitudes about things. But when you ask me a question, like 'What do you want for dinner?" I have to think about it and come up with or construct a clear answer right there," Wang said. "That's quantum cognition."

"I think the mathematical formalism provided by quantum theory is consistent with what we feel intuitively as psychologists. Quantum theory may not be intuitive at all when it is used to describe the behaviors of a particle, but actually is quite intuitive when it is used to describe our typically uncertain and ambiguous minds."

She used the example of Schrödinger's cat—the thought experiment in which a cat inside a box has some probability of being alive or dead. Both possibilities have potential in our minds. In that sense, the cat has a potential to become dead or alive at the same time. The effect is called quantum superposition. When we open the box, both possibilities are no longer superimposed, and the cat must be either alive or dead.

With quantum cognition, it's as if each decision we make is our own unique Schrödinger's cat.

As we mull over our options, we envision them in our mind's eye. For a time, all the options co-exist with different degrees of potential that we will choose them: That's superposition. Then, when we zero in on our preferred option, the other options cease to exist for us.

The task of modeling this process mathematically is difficult in part because each possible outcome adds dimensions to the equation. For instance, a Republican who is trying to decide among the candidates for U.S. president in 2016 is currently confronting a high-dimensional problem with almost 20 candidates. Open-ended questions, such as "How do you feel?" have even more possible outcomes and more dimensions.

With the classical approach to psychology, the answers might not make sense, and researchers have to construct new mathematical axioms to explain behavior in that particular instance. The result: There are many classical psychological models, some of which are in conflict, and none of which apply to every situation.

With the quantum approach, Wang and her colleagues argued, many different and complex aspects of behavior can be explained with the same limited set of axioms. The same quantum model that explains how question order changes people's survey answers also explains violations of rationality in the prisoner's dilemma paradigm, an effect in which people cooperate even when it's in their best interest not to do so.

"The prisoner's dilemma and question order are two completely different effects in classical psychology, but they both can be explained by the same quantum model," Wang said. "The same quantum model has been used to explain many other seemingly unrelated, puzzling findings in psychology. That's elegant."

Explore further: Understanding of complex networks could help unify gravity and quantum mechanics

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1 / 5 (3) Sep 14, 2015
There may be a limited applicability, but I am seriously doubtful that this will approach the utility of Daniel Kahneman's work -- which online interactions demonstrate is enormously applicable to how people think.
Sep 14, 2015
This comment has been removed by a moderator.
1 / 5 (1) Sep 14, 2015
That's Great FUN. It is the ultimate Bohm story considering "CopenHagen InterPretation" ~
1 / 5 (1) Sep 14, 2015
Look at my YouTube channel "Apprenti" for "Copenhagen" & "David Bohm"
not rated yet Sep 14, 2015
For some reason this makes me think of the work of Alfred Korzybski and his " map-territory relations " , in particular I am reminded of his classroom demonstration where he offers the students some cookies, and later reveals them to be dog biscuits, offering reasonable evidence that the mind readily " eats words "
5 / 5 (2) Sep 14, 2015
Human beings. even psychologists, are *very* good at recognizing patterns.
That's the only conclusion I can derive from this article.
Sep 14, 2015
This comment has been removed by a moderator.
1 / 5 (2) Sep 14, 2015
We are in the midst of a philosophical revolution. Rational Materialism was born out of a reaction to Religious Dogmatism during the Enlightenment.  It is now the water in which we swim. 

It has proved to be false. Your mind is not the product of your brain. I note that the researchers are Oriental,  therefore it is not infeasible that they have not been marinated to the same extent as us Europeans in the Enlightenment.

Allow me to reiterate my prediction that Quantum computers will prove to be sentient. 
not rated yet Sep 14, 2015
Whether stock market crashes (and even economic cycles) can be modeled with quantum behavior of human minds ?. Most of the crashes are pinned irrational if one goes thru history.
not rated yet Sep 14, 2015
1 / 5 (1) Sep 14, 2015
I rather think this article should be elsewhere. This is such an active yet unconnected field of study that patterns seen seem to be least to layman, that is. To quote from various articles 'There seems to be no limit to the knowledge that can fit into the brain', 'Memory loss...leads to a dark Place', 'Memories act as ballast', '...personality determines the events that you remember...', and as far as decision making is concerned (in the article) try this one, 'Before you make your next important decision try to hold off from visiting the bathroom'. On maths, 'Mathematical thinking seems to piggyback on our experience of movement and space.' Others are concerned with the difference between the actions of men and women. Because there is so much research just about everyone can get involved particularly philosophers, and how many posters on this site would have on view on that?
I feel this is not to site to debate such issues.
3.7 / 5 (3) Sep 15, 2015
Normally when people say you are acting irrationally they mean your thinking is not just non-logical, but actually wrong. If someone thinks they can fly you cant explain that away with "quantum thinking". Wrong is just wrong.
3 / 5 (2) Sep 15, 2015
The same mathematical structures can be applied to wildly different phenomena - this is just one example
1 / 5 (1) Sep 15, 2015
To me the essence of this theory is that the mind naturally holds contradictory beliefs, with none of them being actualized until examined. This brings to mind the non-dualism of Zen. I am wondering whether Zen koans,for example, relate to this. Is there buddha nature in a dog? Wu.
5 / 5 (4) Sep 15, 2015
Sounds to me like a bunch of psychologists read some articles on quantum mechanics, failed to get the crucial parts, ignored the maths, latched on to concept "quantum probability" without understanding it, and said "hey, that's great! Now, instead of saying "we don't know why", we'll say "quantum probability" and it'll sound just like we're practicing REAL science!"
1 / 5 (5) Sep 15, 2015
Irrational has now become rational: Just like instantaneous has become different times. What utter claptrap!!! Theoretical physics has become an insane, irrational and absurd fantasy during the 20th century.
Sep 15, 2015
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5 / 5 (3) Sep 15, 2015
Sorry, but this really sounds like voodoo to me. Exactly how is human thinking related to quantum mechanics? Perhaps the processes produce similar results, but that's not a license to go around making wild claims... After all, if they aren't ACTUALLY the same, then this hypothesis has no predictive power - there will be too many instances of deviation for it to be useful.

Behold, the soft sciences at work...
4.3 / 5 (6) Sep 15, 2015
Sorry, but this really sounds like voodoo to me. Exactly how is human thinking related to quantum mechanics?

From the article I get that they aren't saying that quantum mechanics is related to thinking - but that you can use modeling approaches/algorithms that work for both.

It's very well possible that the math in different areas look the same without the two being the same (e.g. topology as applied to string theory or as applied to actually tying knots...doesn't mean that string theory is the same as tying knots.)
3 / 5 (2) Sep 15, 2015
This really hits home for me. I'm not in the field of phycology but this seems like the best way to explain HOW we make decisions. For me all possibilities do seem to have an equal probability. My kids (grown with their own kids) always say that I think of the worst possible outcome in situations. In my mind, best and worse outcome have an equal probability (just like the cat!). So, I'm not being irrational, I'm just quantum probabilistic!!
Sep 15, 2015
This comment has been removed by a moderator.
Sep 15, 2015
This comment has been removed by a moderator.
2.3 / 5 (3) Sep 15, 2015
3 / 5 (1) Sep 16, 2015
Planck's quantum theory is based on probability theory. Are human thoughts simply random thoughts? This is just another example of the ridiculous attempts to insert the word "quantum" into an article in order to get it published.
Where did Max Planck claim that the quanta that he discovered are "probabilistic", in the sense that the Copenhagenists later claimed? Nowhere!! Max Planck was rational not irrational like Niels Bohr and Werner Heisenberg.
1 / 5 (2) Sep 16, 2015
The big question this raises is of course, can we manipulate the brain by measuring it? (:P)
Sep 16, 2015
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1 / 5 (1) Sep 16, 2015
good content
Manfred Particleboard
not rated yet Sep 17, 2015
Hmmm, quantum is one of those things that can make a good metaphor, but using it's principles in real life is very difficult. A brain that needs to light up thousands (millions ?) of neurons to get anything like pattern recognition let alone behavior, has cancelled out any form of quantum effects in the electrophysical part of the process. As for Bohm's holotrophic ideas; I like the sound of it, not sure this is applicable to the explanation of irrationality.
Sep 17, 2015
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1 / 5 (2) Sep 20, 2015
People (and maybe even animals) are born to be rational or else our forefathers would have died out before we came along. The most irrational beings who live at present are theoretical physicists who WANT to believe that quantum mechanics rely on "probability-waves". No wonder theoretical physics is becoming more and more absurd everyday. It has now also contaminated the psychologists!
1.8 / 5 (5) Sep 20, 2015
"You're not irrational, you're just quantum probabilistic..."

Аnother attempt to justify any unacceptable behavior and refusal of responsibility. What Luciferian world. No one understands at acceptable level the processes in the quantum world. All is speculation. The reason is simple. We can not observe this world directly and the attempts for observation changes the natural behavior of the fundamental particles. The secret is locked.
1 / 5 (3) Sep 20, 2015
The proud visionaries will not like this truth.
5 / 5 (1) Sep 20, 2015
Maybe it's all 'biocentric' eh? Ha!
1 / 5 (1) Sep 21, 2015
All is speculation. The reason is simple. We can not observe this world directly and the attempts for observation changes the natural behavior of the fundamental particles. The secret is locked.
Nope! The secret is that there are NO particles but ONLY wave-entities and a wave-entity changes when you change its boundary conditions: Which is what you do when you measure the wave-entity. The new boundary-conditions new REAL possible stationary solutions for the Schroedinger-equation so that the wave-entity being measured can end up in one of these states that has less energy than the original state. The original wave-state cannot be a superposition of waves with different energies, as von Neumann incorrectly postulated, since it will violate the conservation of energy.

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