Renfrew's Celtic Scenario

[petegray]

>Greek and Sanskrit share many retained PIE features
> -- the present, aorist and perfect, for instance.

This is a chicken and egg situation.   The present, aorist and perfect *as
tenses* are read back into PIE from Greek and I-I alone.   We cannot
therefore say whether they are "retained archiasms" or "shared innovations".

The various formations - s suffix, reduplication, secondary endings etc etc
are scattered all over PIE, but those tenses as part of a tense system are
only in those two language groups.

Peter