By taking the linguistic evidence too literally one could conclude that the original Indo-European speakers knew butter, but not milk; snow and feet … - A. Berriedale Keith

We learn from the Vedic Index: "In some passages the Panis definitely appear as mythological figures , demons who withhold the cows or waters of heaven ... It is difficult to be certain who a Pani was. It is, however, hardly necessary to do more than regard the Panis generally as non-worshippers of the gods favoured by the singers; the term is wide enough to cover either the aborigines or hostile Aryan tribes as well as demons. "

The same terms are applied indifferently to the human enemies of the Aryans and to the fiends, and no criterion exists by which references to real foes can be distinguished in every case from allusions to demoniacal powers." "Individual Dasas" whom Keith picks out as human examples "are Ilibica, Dhuni and Chumuri, Pipru, Varchin , and Cambara, though the last at least has been transformed by the imagination of the singers into demoniac proportions".

Dasyu, a word of some- what doubtful origin, is in many passages of the Rigveda clearly applied to superhuman enemies... Dasa, like Dasyu, sometimes denotes enemies of a demoniac character in the Rigveda.