Case File · Est. 2026 Evidence Over Outrage
Standing Reference · Social Psychology

What it takes to move a room

Two confederates, thirty-six slides, and a finding that a room doesn't need a majority to bend — it needs consistency.

Moscovici, S., Lage, E. & Naffrechoux, M. (1969). "Influence of a consistent minority on the responses of a majority in a color perception task." Sociometry, 32(4), 365–380.

What they did

172 female participants, in groups of six, were told they were taking part in a color-perception task and shown 36 slides — all of them clearly shades of blue, with brightness varied slightly. Two of the six people in each group were confederates working with the researchers. Everyone stated the color of each slide out loud.

  • Consistent condition: the two confederates called every one of the 36 slides "green."
  • Inconsistent condition: the confederates called 24 slides "green" and 12 "blue."

What they found

  • In the consistent condition, real participants agreed with the "green" answer on about 8.4% of trials — far above a control group with no confederates, which came in near 0%.
  • 32% of participants in the consistent condition gave the wrong ("green") answer at least once.
  • In the inconsistent condition, agreement dropped to about 1.25% — barely above the control group. Consistency, not confidence or numbers, was what produced the effect.
  • In a follow-up individual task, participants who had been in the consistent-minority group judged ambiguous blue-green discs as more green than participants who hadn't — even alone, with no confederates present. Their private perceptual threshold had shifted, not just their public answer.
"Consistency gives the impression that the minority is convinced it is right and committed to its viewpoint." — commonly cited interpretation of Moscovici's consistency findings

Worth knowing before citing this one

Scale the claim to the actual numbers

This finding gets summarized, understandably, as "two people can shift a room's answers" — which is true, but the size of the shift was modest: agreement on 8% of individual trials, not a majority conversion. The more striking and better-supported part of the finding is the private, individual shift documented afterward, when no confederates were even present. Lead with that if you're citing it, rather than implying the room "turned green."

The sample was also 172 American women specifically — later replications have found the general consistency effect holds across other populations, but the original study itself doesn't establish that on its own.