Abstract

PAUL THAGARD’S DEMARCATION CRITERIA S u m m a r y In Paul Thagard’s article “Why Astrology Is a Pseudoscience”, we might find some demarcation criteria which are best used in determining whether certain fields with a lot of practitioners can be claimed to be pseudoscientific. Theory T for the pseudoscience club is if T has long been less progressive than its competitors and faces many more unsolved problems; and, adherents to T do not try to develop the theory to solve puzzles, do not attempt to evaluate T with respect to its alternatives, and are highly reserved and selective in seeking confirmation and falsification. Ten years later Thagard gave us new proposals. If T is a pseudoscience, then it is usually the case that (1) T is neither simple nor unified; the explanations, resources, (2) and predictions of T tend to be ad hoc, spurious, or ill-fitted to the rest of T; or, (3) adherents to T do not try to develop the theory to solve puzzles, do not attempt to evaluate T with respect to competitors, and (4) are highly reserved and selective in seeking confirmation and falsification. In this article, Paul Thagard’s criteria of demarcation are examined and evaluated from the point of view of the history of astrology.