Science is inductive, not deductive; as such, it is not in the business of manufacturing absolute truths or deductive proofs.
As already stated here, a Fact in science is a synonym for an observation. The goal is to obtain objective and unbiased information about the world; an observation represents such information.
Oservations can occur either directly(sight, sound, touch, smell) or indirectly(analog or digital measuring device.) The goal is to receive information from the external world that confirms what is thought to be true or what one expects to be true. Based on the information received, one can formulate a relationship among independants. When such information repeats itself and/or follows a general pattern of appearance, one can draw conclusions or create a theory to explain the patterns of such information.
In order to be considered a 'Fact' in science, one observation alone will not do. It is not sufficient for only one observer to receive the information; rather, the information needs to be available to more than one observer on more than one occasion - it needs to be repeatable.
Thus, to be established, Scientific 'Facts' require not only an observation, but also verification.
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I would like to add the following:
Given this definition, The Theory of Evolution in it's current form would not be considered a Scientific 'Fact', nor would any theory that models a phenomenon that cannot be observed directly.
Obviously, due to the nature of the mechanisms involved, such models are not repeatable or observable in a lifetime. Certainly, the theory of mutation and selection makes predictions that can be verified on the micro level; however, such observations are not adequate to establish a macro scale change as fact. That can come only through observational verification.
Scientific Theories such as Evolution are formally considered Inferential rather than Factual. Do not confuse this with the implication that such a theory is by definition false; there is no current observation which falsifies the theory, nor is there information which indicates inconsistency with established facts.
Edited by Grizz, : addition
Edited by Grizz, : No reason given.
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