The New International Encyclopædia/Freethinker
FREETHINKER. One who forms his theological or religious beliefs by the exercise of his own reason, instead of accepting them on authority. The term came into common use early in the eighteenth century, after the publication of Anthony Collins's Discourse of Freethinking, occasioned by the Rise and Growth of a Sect called Freethinkers (London, 1713), and was applied particularly to the English Deists. (See Deism.) It has been used to designate rationalists, infidels, or skeptics.