Methods of Psychology Early 20th century in Germany, Horse (called Clever Hans) trained by his owner Mr. von Osten. Could answer questions correctly Various scholarly disciplines Yes/No questions: movement of head, hoof taps Psychologist Oskar Pfungst discovered that he didn't understand the questions but simply reacted to visual signs by people around who knew the correct answers. After question was asked: People counted the taps Showed upward movement of head/eyebrows when correct number was reached Slight automatic movement of head Clever Hans simply responded to gestures. An Observation is an objective statement that reasonable observers agree is true. (e.g. patterns of behavior) Reaction of horse gave impression as if he was answering correctly A theory is an idea/conceptual model that is designed to explain existing observations. Von Osten thought that horses have human-like intelligence. A hypothesis makes predictions about new observations made from a theory. Clever Hans could learn about scholarly disciplines & answer correctly Circle of Science Observations Hypothesis/research studies Theories Science walks on two legs: theory & observations The Lessons The Value of Skepticism Many people (von Osten & psychologists before Pfungst) want to believe in extraordinary claims. The more extraordinary the claim, the stronger evidence for a new theory is required. Pfungst was skeptical & engaged in critical thinking. Alternative perspectives & tests to prove them Parsimony (Occam's razor) - simplest explanation is usually preferred when there is more than one. The Value of Careful Observations Under Controlled Conditions Pfungst identified conditions under which Hans could answer (in-)correctly. Identified cues Hans's examiners send Experiments in which he produced/withheld such cues & recorded Hans's reactions The Problem of Observer-Expectancy Effects Observers (people who conduct research) may unintentionally communicate to subjects (Hans) Subjects behave as they "should" behave