Cause and Effect
Cause and effect is the panacea for researchers. It is a term you've likely heard many times already, or will hear many times as you study psychology. Psychologists look to identify the "effect" one variable has on other variables...does one variable "cause" other variables to change. Establishing cause and effect is not easy and requires researchers to conduct studies that not only follow the scientific method, but also classify as "true experiments" (studies that include random assignment of participants to groups and manipulation of an independent variable). For example, can a psychologist truly say that smoking causes cancer? Can we conduct a true experiment on the effects of smoking...can you randomly assign participants to smoking and non-smoking groups, have them smoke or not smoke for a period of time and then measure the growth of cancer? You could, but not ethically. As a result, you can't establish a cause and effect relationship...you can establish that one variable (smoking) influences the other (cancer) using a correlational approach, but you really can't establish cause and effect.