Presentation on theme: "From social psychology to sociology - a physicist’s point of view Katarzyna Sznajd-Weron Institute of Theoretical Physics Wrocław University Praha, November."— Presentation transcript:
From social psychology to sociology - a physicist’s point of view Katarzyna Sznajd-Weron Institute of Theoretical Physics Wrocław University Praha, November 6, 2003
Plan Can we explain global changes by microscopic models? Can we treat people like particles? Examples of social experiments. Social psychology and sociology. A simple model.
Almost a century ago physicists asked the question: Can phase transitions be explained by microscopic theory? T M T* ferromagnetparamagnet
Back to 1920... Wilhelm Lenz proposed a very simple microscopic model of interacting spins.
Was it only hope? Spontaneous magnetization cannot be explained using this model in its 1D version.
After two decades hope became reality Onsager showed that the 2D version of the model can explain the critical phase transition. Very simple local interactions can lead to qualitative changes on the macroscopic scale. T M T*
The hope outside Physics Rapid changes on macroscopic scale appear in various systems. Mostly these changes are unexpected. Usually there is no obvious reason for them. Can we explain them in terms of microscopic interactions like we did for physical systems?
People sometimes behave like particles Conformity The Millgram experiment: Obedience to Authority The Asch experiment: peer pressure Social validation
Stanley Millgram: Obedience to Authority (Yale, 1961-62)
Stanley Milgram (1973) Journal of Abnormal and Social Psychology voltslearnerexperimenter 90Ou!Please continue 105Ou! (lauder)It is essential that we continue.... 120Ou! It hurts!Continue, it’s necessary 135Ou! It is really painfulThe experiment requires that you go on until he has learned all the word pairs correctly 150Let me leave! My heart... You have no other choice
What will happen? – ask psychiatrists and psychologists Predicted: most subjects would not go beyond 150 volts, when the victim makes his first explicit demand to be freed. Only 4% would reach 300 volts. Only a pathological fringe of about 0.1% would use the highest shock on the board.
Solomon E. Asch - a pioneer of social psychology Solomon E. Asch, born in Warsaw in 1907, he came to the United States in 1920 and received a Ph.D. from Columbia University in 1932. Experiment of conformity (without Authority), 1956
Asch(1951-1955) – the experiment on visual perception? The experimenter asks to choose which of the three lines on the left matches the length of the one on the right.
Results of the Asch experiment: social pressure 76% conformed to the majority at least once. Conformity became more frequent as group size increased. “The tendency to conformity in our society is so strong that reasonably intelligent (...) people are willing to call white black” /Asch/
There are some limits... 12345678910 0% 10% 20% 30% 40% Number of people against Mistakes
The power of social validation Milgram, Bickman & Berkowitz, 1969 Results of experiments: 1 4%, 5 80% Robert B. Cialdini: Social Validation – the fundamental way of decision making