f different classes. Diodorus
refers to the Celtic philosophers and theologians (Druids), diviners,
and bards, as do also Strabo and Timagenes, Strabo giving the Greek form
of the native name for the diviners, [Greek: ouateis], the Celtic form
being probably _vatis_ (Irish, _faith_).[1018] These may have been also
poets, since _vatis_ means both singer and poet; but in all three
writers the bards are a fairly distinct class, who sing the deeds of
famous men (so Timagenes). Druid and diviner were also closely
connected, since the Druids studied nature and moral philosophy, and the
diviners were also students of nature, according to Strabo and
Timagenes. No sacrifice was complete without a Druid, say Diodorus and
Strabo, but both speak of the diviners as concerned with sacrifice.
Druids also prophesied as well as diviners, according to Cicero and
Tacitus.[1019] Finally, Lucan mentions only Druids and bards.[1020]
Diviners were thus probably a Druidic sub-class, standing midway between
the Druids proper and the bards, and partaking of some of the functions
of both. Pliny speaks of "Druids and this race of prophets and
doctors,"[1021] and this suggests that some were priests, some diviners,
while some practised an empiric medical science.

On the whole this agrees with what is met with in Ireland, where the
Druids, though appearing in the texts mainly as magicians, were also
priests and teachers. Side by side with them were the _Filid_, "learned
poets,"[1022] composing according to strict rules of art, and higher
than the third class, the Bards. The _Filid_, who may also have been
known as _Fathi_, "prophets,"[1023] were also diviners according to
strict rules of augury, while some of these auguries implied a
sacrifice. The Druids were also diviners and prophets. When the Druids
were overthrown at the coming of Christianity, the _Filid_ remained as a
learned class, probably because they had abandoned all pagan practices,
while the Bards were reduced to a comparatively low status. M. D'Arbois
supposes that there was rivalry between the Druids and the _Filid_, who
made common cause with the Christian missionaries, but this is not
supported by evidence. The three classes in Gaul--Druids, _Vates_, and
Bards--thus correspond to the three classes in Ireland--Druids, _Fathi_
or _Filid_, and Bards.[1024]

We may thus conclude that the Druids were a purely Celtic priesthood,
belonging both to the Goidelic and Gaulish branches of th