Overview
Scientific skeptics believe that empirical investigation of reality leads to the truth, and that the scientific method is best suited to this purpose. Considering the rigor of the scientific method, science itself may simply be thought of as an organized form of skepticism. This does not mean that the scientific skeptic is necessarily a scientist who conducts live experiments (though this may be the case), but that the skeptic generally accepts claims that are in his/her view likely to be true based on testable hypotheses and critical thinking.
Scientific skeptics attempt to evaluate claims based on verifiability and falsifiability and discourage accepting claims on faith or anecdotal evidence. Skeptics often focus their criticism on claims they consider to be implausible, dubious or clearly contradictory to generally accepted science. Scientific skeptics do not assert that unusual claims should be automatically rejected out of hand on a priori grounds - rather they argue that claims of paranormal or anomalous phenomena should be critically examined and that extraordinary claims would require extraordinary evidence in their favor before they could be accepted as having validity.
From a scientific point of view, theories are judged on many criteria, such as falsifiability, Occam's Razor, and explanatory power, as well as the degree to which their predictions match experimental results. Skepticism is part of the scientific method; for instance an experimental result is not regarded as established until it can be shown to be repeatable independently.
By the principles of skepticism, the ideal case is that every individual could make his own mind up on the basis of the evidence rather than appealing to some authority, skeptical or otherwise. In practice this becomes difficult because of the amount of knowledge now possessed by science, and so an ability to balance critical thinking with an appreciation for consensus amongst the most relevant scientists becomes vital.
Not all fringe science is pseudoscience. For instance, some proponents of repressed memories apply the scientific method carefully, and have even found some empirical support for their validity, though the theories have not received complete scientific consensus.
Empirical or scientific skeptics do not profess philosophical skepticism. Whereas a philosophical skeptic may deny the very existence of knowledge, an empirical skeptic merely seeks likely proof before accepting that knowledge.
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