Your browser doesn’t support HTML5 audio
Want to learn more?
A theory not only explains known facts; it also allows scientists to make predictions of what they should observe if a theory is true. Scientific theories are testable. New evidence should be compatible with a theory. If it isn’t, the theory is refined or rejected. The longer the central elements of a theory hold–the more observations it predicts, the more tests it passes, the more facts it explains–the stronger the theory.
But for scientists, a theory has nearly the opposite meaning. A theory is a well-substantiated explanation of an aspect of the natural world that can incorporate laws, hypotheses and facts. The theory of gravitation, for instance, explains why apples fall from trees and astronauts float in space. Similarly, the theory of evolution explains why so many plants and animals–some very similar and some very different–exist on Earth now and in the past, as revealed by the fossil record.
There are several theories and models that support the practice of health promotion and disease prevention. Theories and models are used in program planning to understand and explain health behavior and to guide the identification, development, and implementation of interventions.
When identifying a theory or model to guide health promotion or disease prevention programs, it is important to consider a range of factors, such as the specific health problem being addressed, the population(s) being served, and the contexts within which the program is being implemented. Health promotion and disease prevention programs typically draw from one or more theories or models.
“I think that was carrying your theory a little too far,” said the professor dubiously.
He keeps playing with action as an artist plays with a theory.