Modern science is source and repository of man’s objective knowledge. Scientific knowledge is siloed in models.  A model maps a fact to a future unrealized fact as a prediction. A fact is a measurement.  A measurement is an observation tied to a scale with an expressed error. An observation is a registration of the real world on our senses or sensing equipment.

A model’s validation derives entirely from its predictive power.  There are four grades of model ranked by predictive strength and they are conjecture, hypothesis, theory, and law. 

Predictive power is evidence of and reason for sciences’ objectivity, the sole source of science’s reliability and the demarcation between science and pseudoscience. Predictive power as determinant of a scientific model’s validity provides the basis for any rational trust of science.

Models are predictions mapping a fact to an unrealized fact where the current fact constitute the premises and the unrealized fact the conclusion of an inductive argument.  Induction derives conclusions from premises with probability and not certainty. All scientific knowledge is therefore the fruit of induction validated by predictive power which is a measure of probability. 

– Greg Glassman