The psychological tricks needed to sell the first lightbulb | Nudge Newsletter


The Mere Exposure Effect

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Loyal fans of Nudge will have heard me talk about the mere exposure effect.

In 1969, psychologist Robert Zajonc¹ found that students rated unfamiliar Turkish words more favourably when they had seen them more often.

It's not a revolutionary finding. We prefer things we're familiar with.

And many great inventors knew this instinctively.

Thomas Edison understood that while the lightbulb was revolutionary, new inventions could frighten people.

To ease this fear, he embraced mere exposure and made the bulb more familiar.

Specifically, he mimicked gaslighting in several ways:

  • Similar brightness to gas lamps
  • Added light shades (used on gas to stop flickering in a draft—but unnecessary for electric bulbs).
  • Ran electric cables underground just like gas pipes.

Edison wrote his goal was to “imitate all done by gas” so the transition felt natural rather than disruptive.

Innovations spread faster when they blend the new with the familiar. — Phill

P.S. This wonderful insight is taken from Richard Shotton's great book Hacking The Human Mind. I interviewed him last week, and his episode will be out soon.

¹Zajonc, R. B., & Rajecki, D. W. (1969). Exposure and affect: A field experiment. Psychonomic Science, 17, 216–217.

As a behavioural science practitioner, I believe in the peak-end rule.

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