In 1868, Darwin set out to quantify human emotion in a series of novel experiments. He took advantage of a new technology, photography, to capture people whose faces were artificially contracted by harmless electrical probes into expressions resembling those of emotions running from deep sadness to elation. Then, he showed those photos to viewers who interpreted the emotions so Darwin could assess their universality. The Scientist quotes Darwin’s conclusion, published in The Expression of the Emotions in Man and Animals: “The young and the old of widely different races, both with man and animals, express the same state of mind by the same movements.”
Is this true, however? Darwin’s experiment only included 20 participants, mostly his friends and family, and he threw out some of the data. Moreover, do we still interpret emotions the same way as we did nearly 150 years ago?
To find out, researchers from the University of Cambridge are recreating Darwin’s experiments. This time, the experimenters called upon more than 18,000 anonymous Internet participants to view the same 11 photographs Darwin used in his own tests.
Unfortunately, the results are still out for analysis, but the researchers did draw a few initial conclusions. Basic emotions such as terror and surprise tend to elicit consensus, for example, but those meant to portray more complex feelings—deep grief, for example—received a mixed bag of responses. Boredom, perhaps, is the most varied of the photographs. Boredom as an emotion, it seems, simply did not exist back in Darwin’s days. What modern participants view as bored, Darwin and his contemporaries labeled “hardness.”
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