Great Apes Know When You’re Wrong

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Written By Animalcognition

Humankind’s closest relatives are proving that not only can they recognize when a human believes something that’s false, but that they will often help correct that false belief.

A recent study1 done by researchers from the Max Planck Institute for Evolutionary Anthropology in Germany tested for this advanced level of theory of mind in great apes (Orangutans, gorillas, chimpanzees, and bonobos). Theory of mind is the ability to understand what others may be thinking and feeling, and consequently, the ability to predict which actions they will take as a result of their state of mind.

Previous research suggested that great apes do indeed have theory of mind.2 They can follow the gazes of fellow apes, and even interpret human facial expressions. As recently as October 2016, great apes also showed promising signs that they understand the concept of false beliefs.3 An experiment had apes observe a human enter an area, see an object in one location, then leave the area. While the human was gone, the apes continued to observe as the object was moved to another location.

When the human returned, the apes seemed to anticipate that the human would look for the object in the location the human had last seen it. This was judged by tracking where the apes looked as they observed the returning human. Thanks to their theory of mind, the apes seemed to have understood that the returning human was likely unaware that the object had been moved.

The scientists at the Max Planck Institute wanted to go further in their study, by testing whether the apes would take action when they saw a human acting on a false belief.

Great apes understand false beliefs


The MPI experiment had a similar setup, with apes observing while a human put an object in one locked box, then left the room. While they were gone, the object was moved to another locked box. When the human returned, they predictably tried to unlock the box that they had originally put the object in.

This time, however, the apes could participate. All of the apes were taught how to unlock the boxes, so they could step in and open one themselves if they wanted to.

Much like human babies do in the same type of test, the helpful apes tended to step in and assist when they saw that the human was trying to unlock the wrong box. They were less likely to do this in alternate scenarios where the human would open the correct box. By helping out, the apes demonstrated “pro-social” behavior, geared toward cooperation. Their understanding of false beliefs in others is a sign of advanced social cognition.

“Social cognition is the sum of cognitive abilities necessary to survive in a social world,” said the study’s lead scientist, David Buttelmann. “Whenever individuals interact, they need to understand the gestures, motivations, feelings, intentions, and beliefs of their partners.”

“I would love to develop interactive false-belief tests for other species. This way we will be able to track the development of our own mind and understand, at some point, what made us uniquely human.”


This article was written by Amanda Pachniewska, founder and editor of


1 – David Buttelmann , Frances Buttelmann, Malinda Carpenter, Josep Call, Michael Tomasello
Great apes distinguish true from false beliefs in an interactive helping task

2 – Michael Tomasello, Josep Call, Brian Hare
Chimpanzees understand psychological states – the question is which ones and to what extent
Trends in Cognitive Sciences

3 – Christopher Krupenye, Fumihiro Kano, Satoshi Hirata, Josep Call, Michael Tomasello
Great apes anticipate that other individuals will act according to false beliefs