People who think their view is unpopular go quiet, making it seem even rarer

German political scientist Elisabeth Noelle-Neumann proposed in 1974 that people constantly sense which opinions are gaining or losing ground, and those who feel in the minority speak up less to avoid isolation. Their silence makes the view look less common than it is, so even more people stay quiet. The 'spiral of silence' helps explain why polls and public debate can drift apart.

— Elisabeth Noelle-Neumann, The Spiral of Silence: A Theory of Public Opinion — Journal of Communication, 1974
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