James Swift

21 January 2022

Strategist’s Digest: We are becoming less rational and more emotional 

Contagious digests the most interesting and relevant research from the world of advertising and beyond, because there’s just too much to read and too little time

The rise and fall of rationality in language 

By Marten Scheffer, Ingrid van de Leemput, Els Weinans, and Johan Bollen. Published in Proceedings of the National Academy of Sciences of the United States of America.

Give it to me in one sentence.

Over the past 40 years, public interest has shifted from rationality to emotion, and from collective interests to individuality.

Give me a little more detail.

The researchers searched millions of English and Spanish-language books published between 1850 and 2019, measuring the prominence of 5,000 of the most common words.

From 1850 onwards, words associated with reasoning, such as ‘determine’ and ‘conclusion’ rose while those connected to emotion, such as ‘believe’ or ‘feel’, fell.

But from around 1980, that pattern reversed. Emotional words became more prominent as rational words declined. At the same time, singular pronouns began to appear more than collective ones.

In further experiments, the researchers showed this same shift was evident in fiction and non-fiction books, within the New York Times archive of articles, within smaller datasets of other languages beyond English and Spanish, and since 2004, within Google search trends.

Why is this interesting?

Bill Bernbach famously said that while ‘it is fashionable to talk about changing man [...] a communicator must be concerned with unchanging man’. We’re not going to argue the point but it is good to remember that, over the medium and long term, people can change in quite significant ways.

We also thought the study was interesting in light of Orlando Wood’s book, Lemon, which discussed a society-wide shift from right-brain thinking to left-brain thinking, and what this meant for brands.

Any weaknesses?

We don’t know why it is happening. The authors posit that the shift could have something to do with neoliberal policies, which were hard to criticise rationally but left a lot of people feeling hard done by. They also suggest social media has had a hand in things because the shift accelerated from around 2007. But these are just theories.

Also, the findings may not be applicable globally. The bulk of the research was done on English and Spanish books, and a smaller amount was done on a handful of other languages (German, French, Italian and Russian), but that leaves a lot of the world out of the frame.

Where can I find the whole report?

Here, and it’s free at the moment. You can also read a write-up of the report, here.

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