But skepticism as a way of thinking has a long historical tradition that can be traced back at least 2,500 years. The foremost historian of skepticism, Richard Popkin, tells us (1979, p. xiii): “Academic scepticism, so-called because it was formulated in the Platonic Academy in the third century, B.C., developed from the Socratic observation, ‘All I know is that I know nothing.’” Two of the popular received meanings of the word by many people today are that a skeptic believes nothing, or is closed minded to certain beliefs. There is good reason for the perception of the first meaning. The Oxford English Dictionary (OED) gives this common usage for the word skeptic:
One who, like Pyrrho and his followers in Greek antiquity, doubts the possibility of real knowledge of any kind; one who holds that there are no adequate grounds for certainty as to the truth of any proposition whatever (Vol. 2, p. 2663).
Since this position is sterile and unproductive and held by virtually no one (except a few confused solipsists who doubt even their own existence), it is no wonder that so many find skepticism disturbing. A more productive meaning of the word skeptic is the second usage given by the OED:
One who doubts the validity of what claims to be knowledge in some particular department of inquiry; one who maintains a doubting attitude with reference to some particular question or statement.