"Although since Christian times Druids have been identified as wizards and soothsayers, in pre-Christian Celtic society they formed an intellectual class comprising philosophers, judges, educators, historians, doctors, seers, astronomers, and astrologers. The earliest surviving Classical references to Druids date to the 2nd century B.C.

"The word "Druidae" is of Celtic origin. The Roman writer Pliny the Elder (Gaius Plinius Secundus, 23/24-79 A.D.) believed it to be a cognate with the Greek work "drus," meaning "an oak." "Dru-wid" combines the word roots "oak" and "knowledge" ("wid" means "to know" or "to see" - as in the Sanskrit "vid"). The oak (together with the rowan and hazel) was an important sacred tree to the Druids. In the Celtic social system, Druid was a title given to learned men and women possessing "oak knowledge" (or "oak wisdom").
- Chris Witcombe