Another area to think about is the "Tantra-yukti" lists that occur in the ArthaÅ›Ästra, CarakasaṃhitÄ and SuÅ›rutasaṃhitÄ. There's a good account of them in Antonella Comba's
La medicina indiana classica and in Dasgupta's
History of Indian Philosophy v.2 ch.13. These are like general paribhÄá¹£Äs that appear to be very old and were applied in several Å›Ästras, including especially nyÄya.