Surveys on the Existence of Extraterrestrial Intelligent Life and Effects of Revealing Expert Consensus

Abstract: Vickers et al. (2025) established that 58.20% of astrobiology experts believe intelligent extraterrestrial life likely exists, providing the first empirical baseline for public comparison. We surveyed 6,114 highly educated and scientifically engaged individuals (77.60% bachelor's degree+; 67.99% high-to-very-high scientific engagement) to assess their beliefs about extraterrestrial intelligent life existence: (1) personal beliefs, (2) perceived social circle beliefs, (3) perceived expert beliefs, and (4) responses to expert consensus revelation. Results showed 95.01% believed extraterrestrial intelligent life exists, with 62.59% holding definitive rather than probable convictions. Participants exhibited massive pluralistic ignorance, a 'cosmic closet', underestimating social circle beliefs by 46.07 percentage points despite near-universal personal conviction. Participants also exhibited a novel 'conviction intensity gap': while overestimating expert belief prevalence (67.63% vs. 58.20% actual), they underestimated expert conviction strength, perceiving only 21.10% as holding definitive beliefs. Experimental revelation of actual consensus (N = 5,106; 83.51% passed manipulation check) produced negligible personal belief change (d = -0.11) and small social belief change (d = 0.14). These findings demonstrate that consensus misperception operates along two dimensions, prevalence and intensity, and that even scientifically engaged audiences resist belief revision via expert consensus information.