With the Celts, therefore, learning constituted a kind of priesthood.
These were his moral qualifications. His scientific attainments
require a little longer consideration, as they form the chief
object we have in view.

They may at the outset be stated in a few words. The ollamh was
"a man who had arrived at the highest degree of historical
learning, and of general literary attainments. He should be an
adept in royal synchronisms, should know the boundaries of all
the provinces and chieftaincies, and should be able to trace the
genealogies of all the tribes of Erin up to the first man.--(Prof. Curry,
Lecture X.)

Caesar had already told us of the Druids, "Si de hereditate, si de
finibus controversia est iidem decernunt." In this passage he gives
us a glimpse of a system which he had not studied sufficiently to
embrace in its entirety.

The qualifications of an ollamh which we have just enumerated, that
is to say, of the highest doctor in Celtic countries, already prove
how their literature grew out of the clan system.

The clan system, of which we shall subsequently speak more at
length, rested entirely on history, genealogy, and topography. The
authority and rights of the monarch of the whole country, of the
so-called kings of the various provinces, of the other chieftains in
their several degrees, finally, of all the individuals who composed
the nation connected by blood with the chieftains and kings,
depended entirely on their various genealogies, out of which grew