Methods of Persuasion: How to Use Psychology to Influence Human Behavior

by Nick Kolenda

Leon Festinger, a prominent researcher in social psychology, infiltrated the group with his colleagues. They pretended to be followers of the cult so that they could observe their behavior (pretty dedicated researchers, huh?). Upon witnessing cult members develop stronger beliefs about the end of the world after the flood failed to arrive, Festinger developed an important conclusion: people have a powerful psychological need to maintain consistent attitudes and behavior. That conclusion can help explain why body language can trigger congruent attitudes. If we display certain body language (e.g., head nodding), and if that body language is inconsistent with our inner attitude (e.g., we’re in disagreement), we feel a state of discomfort known as cognitive dissonance, and we become motivated to resolve that discomfort.

Gradual Changes. First, it’s very difficult to detect changes that occur in small increments. There’s a concept known as the just noticeable difference (or the difference threshold), which refers to the minimum amount of change that’s needed in a stimulus in order for people to detect that change (Ono, 1967).