Synthesizes a number of observations
Heuristic; that is, it generates new research
Must generate hypotheses that can be empirically verified
Is a tool and as such cannot be right or wrong; it is either useful or it is not useful
Chosen in accordance with the law of parsimony: Of two equally effective theories, the simpler of the two must be chosen
Contain abstraction, such as numbers or words, which constitute the formal aspect of a theory
The formal aspect of a theory must be correlated with observable events, which constitute the empirical aspect of a theory
All theories are attempts to explain empirical events, and they must, therefore, start and end with empirical observations