To do this, psychologists look for patterns that will help them understand and predict behavior using scientific methods and principles to test their ideas.
David Myers provides an example of how one might conduct a study on the causes of human happiness. First, he explains, we would formulate a theory and create a hypothesis. In this case, we may theorize that human connection is an important factor in happiness, so we may predict that married couples are happier than never-married people. We would then observe behavior either in the lab or real life and record, analyze, and report the findings. Although scientists look for validity and reliability in their findings, sometimes neither is present.
In order to test a hypothesis, researchers use various methods, including surveys, naturalistic observation, and case studies. Robert Epstein explains that while observation tends to be the simplest method, it can be somewhat limited in terms of how much we can actually understand about human nature. The experimenter has no control over the composition of control groups, as in case studies, and therefore cannot randomize subjects.
The next scene provides an example of an experiment in which researchers are testing the effects of gingko biloba on memory. Daniel Gilbert points out the importance of designing experiments that take ethical guidelines into consideration. A well-designed experiment will also take into account the confounding variables and tease them out. Experiments that get results can be replicated, and when the results are consistent through continual replication, people begin to accept the theory.