Festinger & Carlsmith (1959)

Small rewards for engaging in counter-attitudinal change > large rewards for engaging in the same

flowchart LR
a(Strong Reasons for engaging in </br> attitude-discrepant behaviour)-->b(dissonance is weak)
b-->c(attitude change is small)
d(Weak reasons for engaging in attitude </br> discrepant behaviour)-->e(Dissonance is strong)
e-->f(attitude change is large)

notes: but why? what’s the inner, underlying mechanism? was the experiment replicated?

see also: Cognitive Dissonance