We know little of their teaching, which was entirely oral, though it covered so much ground that, according to Cæsar, not less than thirty years of study were needed to become a druid. The Roman conquest dispersed them by degrees; then it was that their disciples, the bards, committed to writing more or less imperfect and mutilated fragments of the teachings of their masters. Their "triads"[123] are undoubtedly akin to Hindu teachings; Evolution results from the manifestation of the Absolute, it culminates in man, who possesses a maximum of individualisation, and terminates in the personal, conscious union of the beings thus created with the ineffable All.
The Absolute is "Ceugant"; manifestation, or the Universe, is "Abred"; the divine state of freed souls is in "Gwynvyd"; these are in the three circles.[124]
In "Ceugant" there is only the Unknowable, the rootless Root. Souls are born and develop in "Abred," passing into the different kingdoms; "Amwn" is the state through which beings pass only once, which means that the "I," when once gained, continues for ever. "Gwynvyd" is the world of perfect and liberated souls, eternal Heaven, great Nirvâna.
During this long pilgrimage, the Monad—the divine fragment in a state of incarnation—undergoes an endless number of rebirths, in myriads of bodies.
"I have been a viper in the lake," said Taliesin, the bard[125]; "a spotted adder on the mountain, a star, a priest. This was long, long ago; since then, I have slept in a hundred worlds, revolved in a hundred circles."
It was their faith in rebirth that gave the Gauls their indomitable courage and extraordinary contempt of death:
"One of their principal teachings," said Cæsar,[126] "is that the soul does not die, but passes at death into another body—and this they regard as very favourable for the encouragement of valour and for inculcating scorn of death."
Up to a few years ago, belief in the return of the soul to earth was still prevalent in those parts of Brittany in which civilisation had not yet exercised its sceptical, materialising influence; there even existed druids—probably degenerate ones—in Great Britain and France; in the Saône-et-Loire district, they seem to have been called the "Adepts of the White Religion"[127]; both in them and in their ancestors, belief in rebirth remained unshakable.