Epistemic vigilance
Communication is a powerful but a dangerous tool. While it allows humans to acquire an unprecedented amount of information, it can also lead to lies, manipulation and deceit. In order for communication to remain evolutionarily stable, individuals have to ensure that most of the communicated information they acquire is true or beneficial. In humans, the solution adopted is to filter incoming communicated information: we calibrate our trust, evaluate arguments, gauge the plausibility of claims, etc. Dan Sperber has dubbed the term epistemic vigilance to refer to this suite of mechanisms.
    It is often thought that the best way to influence people is to stop them from thinking. One of the counterintuitive conclusions that can be derived within this framework is that, on the contrary, the best way to influence people is to tap into recent mechanisms of epistemic vigilance, such as complex trust calibration and reasoning (see here for an explanation of why reasoning can be considered a mechanism of epistemic vigilance). Evidence supporting this claim can be found in this paper, which uses three examples to make its point:

- Subliminal influence, which deprives us of nearly every mean to evaluate communicated information, is tremendously inefficient (50 years of research on subliminal influence have given us the power to get thirsty people to drink a little more water; in the meantime, using good old influence, Stanley Milgram had participants risk shocking other participants to death).

- Non-ostensive communication, such as facial signals of emotions, are typically much less powerful than ostensive communication which allows us much more leeway in the evaluation of information. Moreover, even non-ostensive communication is far from being automatic. For instance, emotional contagion is heavily modulated by the source.

- Reasoning allows people to accept more weird beliefs, including some very counterintuitive ones and, yes, quite a few wrong ones as well.

The Incredulity of
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Sperber, D., Clément, F., Heintz, C., Mascaro, O., Mercier, H., Origgi, G. & Wilson, D. (2010) “Epistemic vigilance”.

Mercier, H. (2013) “Our pigheaded core: How we became smarter to be influenced by other people”. In Calcott, B., Joyce, R. & Sterelny, K. (Eds.) Evolution, Cooperation, and Complexity. MIT Press.

Dezecache, G., Mercier, H. & Scott-Phillips, T. (2013) "An evolutionary approach on emotional communication." Journal of Pragmatics.

Strickland, B. & Mercier, H. (2013) "Bias neglect: A blind spot in the evaluation of scientific results." QJEP
Hugo Mercier,
May 6, 2010, 5:07 PM
Hugo Mercier,
Aug 6, 2010, 1:27 PM