The FIRSTS: Theory of Mind in non-humans (1978)

Although any farmer or pet owner throughout the ages would probably agree that animals can understand the intentions of their owners, not until 1978 has this knowledge been scientifically proven.

Premack & Woodruff (1978) performed a very simple experiment in which they showed videos to a female adult chimpanzee named Sarah involving humans facing various problems, from simple (can’t reach a banana) to complex (can’t get out of the cage). Then, the chimps were shown pictures of the human with the tool that solved the problem (a stick to reach the banana, a key for the cage) along with pictures where the human was performing actions that were not conducive to solving his predicament. The experimenter left the room while the chimp made her choice. When she did, she rang a bell to summon the experimenter back in the room, who then examined the chimp’s choice and told the chimp whether her choice was right or wrong. Regardless of the choice, the chimp was awarded her favorite food. The chimp’s choices were almost always correct when the actor was its favourite trainer, but not so much when the actor was a person she disliked.

Because “no single experiment can be all things to all objections, but the proper combination of results from [more] experiments could decide the issue nicely” (p. 518), the researchers did some more experiments which were variations of the first one designed to figure out what the chimp was thinking. The authors go on next to discuss their findings at length in the light of two dominant theories of the time, mentalism and behaviorism, ruling in favor of the former.

Of course, the paper has some methodological flaws that would not pass the rigors of today’s reviewers. That’s why it has been replicated multiple times in more refined ways. Nor is the distinction between behaviorism and cognitivism a valid one anymore, things being found out to be, as usual, more complex and intertwined than that. Thirty years later, the consensus was that chimps do indeed have a theory of mind in that they understand intentions of others, but they lack understanding of false beliefs (Call & Tomasello, 2008).

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1. Premack D & Woodruff G (Dec. 1978). Does the chimpanzee have a theory of mind? The Behavioral and Brain Sciences, 1 (4): 515-526. DOI: 10.1017/S0140525X00076512. ARTICLE

2. Call J & Tomasello M (May 2008). Does the chimpanzee have a theory of mind? 30 years later. Trends in Cognitive Sciences, 12(5): 187-192. PMID: 18424224 DOI: 10.1016/j.tics.2008.02.010. ARTICLE  | FULLTEXT PDF

By Neuronicus, 20 August 2016

Really? That’s your argument?!

Photo by Collection. Released under FSP Standard License License
Photo by Collection. Released under FSP Standard License

I don’t believe there is a single human being that during an argument has not thought or exclaimed “Really? That’s your argument?” or something along those lines. The saying/attitude is meant to convey the emotional response (often contemptuous) to the identification of the opponent’s argument as weak and unworthy of debate. We seem to be very critical about other people’s reasoning when it does not match our own. On the other hand, we also seem to be a little more indulgent with the strength of our own arguments. This phenomenon has been dubbed “selective laziness”, as one is not so diligent in applying the stringent rules of rational thinking to his/her own line of argumentation.

But what happens when the argument that one so easily dismisses as invalid is one’s own? Trouche et al. (2015) managed to fool 47% (115 individuals) into believing that the arguments for a reasoning choice were their own, when, in point of fact, they were not (see Fig. 1). When asked to evaluate the “other” argument (which was their own), 56% (65 people, 27% of the whole sample) “rejected their own argument, choosing instead to stick to the answer that had been attributed to them. Moreover, these participants (Non-Detectors) were more likely to accept their own argument for the valid than for an invalid answer. These results shows that people are more critical of their own arguments when they think they are someone else’s, since they rejected over half of their own arguments when they thought that they were someone else’s”. (p. 8). I had to do this math on a PostIt, as authors were a little bit… lazy in reporting anything but percentages and no graphs.

Fig. 1 from Trouche et al. (2015). © 2015 Cognitive Science Society, Inc.
Fig. 1 from Trouche et al. (2015). © 2015 Cognitive Science Society, Inc.

The authors replicated their findings to address some limitations of the previous experiment, with similar results. And they provide some speculation about the adaptability of ‘selective laziness’, which, frankly, I think is baloney. Nevertheless, the paper quantifies and provides a way to study this reasoning bias we are all familiar with.

Reference: Trouche E, Johansson P, Hall L, & Mercier H. (9 October 2015). The Selective Laziness of Reasoning. Cognitive Science, 1-15. doi: 10.1111/cogs.12303. [Epub ahead of print]. Article | PDF

By Neuronicus, 15 October 2015