Extract - Wikipedia

Psychologists will make theories to try to explain a behavior or pattern they see. Based on their theory they will make some predictions. They may then carry out an experiment or collect other types of information that will tell them whether their predictions were right or wrong.
Some types of experiments cannot be done on people because the process would be too lengthy, expensive, dangerous, unfair, or otherwise unethical. There are also other ways psychologists study the mind and behavior scientifically, and test their theories. Psychologists might wait for some events to happen on their own; they might look at patterns among existing groups of people in natural environments; or they might do experiments on animals (which can be simpler and more ethical to study).
Psychology shares other things with natural sciences, as well. For example, a good psychological theory may be possible to prove wrong. Just like in any natural science, a group of psychologists can never be completely sure that their theory is the right one; but if a theory can be proven wrong, and yet other psychologists do not successfully prove it wrong, then it is more likely that the theory is accurate. This is called falsifiability.
Scientific psychologists use a lot of different tools as part of their daily work and to carry out their studies. Psychologists use surveys to ask people how they feel and what they think. They may use special devices to look at the brain and to see what it's doing. Psychologists also often use computers so that they can carefully measure when and how people behave, usually in response to pictures, words, symbols, or other stimuli. Psychologists use statistics, too, to help them analyze the data that they get from their experiments.

[change] Symbolic and subjective approaches

Not all psychology is scientific psychology. Psychodynamic psychology and depth psychology do things like interpreting people's dreams to understand the unconscious mind, as in older approaches to psychology begun by Sigmund Freud or Carl Jung.
Humanistic psychology and existential psychology also believe that it is more important to understand personal meaning than to find causes and effects of mental processes and behaviors.