ist em ology , ▁Pr aman as ), ▁value ▁system ▁( axi ology ) ▁and ▁other ▁topics . ▁Indian ▁philosophy ▁also ▁covered ▁topics ▁such ▁as ▁political ▁philosophy ▁as ▁seen ▁in ▁the ▁Ar th ash ast ra ▁c . ▁ 4 th ▁century ▁B CE ▁and ▁the ▁philosophy ▁of ▁love ▁as ▁seen ▁in ▁the ▁K ama ▁S ut ra . ▁The ▁K ural ▁literature ▁of ▁c . ▁ 1 st ▁century ▁B CE , ▁written ▁by ▁the ▁T amil ▁poet - ph il os opher ▁Vall u var , ▁is ▁believed ▁by ▁many ▁sch ol ars ▁to ▁be ▁based ▁on ▁J ain ▁philosoph ies . ▁ ▁Later ▁develop ments ▁include ▁the ▁development ▁of ▁T ant ra ▁and ▁Iran ian - I sl am ic ▁influ ences . ▁Buddh ism ▁mostly ▁disappeared ▁from ▁India ▁after ▁the ▁Muslim ▁con quest ▁in ▁the ▁Indian ▁sub cont inent , ▁surv iving ▁in ▁the ▁H imal ay an ▁regions ▁and ▁south ▁India . ▁The ▁early ▁modern ▁period ▁saw ▁the ▁fl our ishing ▁of ▁Nav ya - N y ā ya ▁( the ▁' new ▁reason ') ▁under ▁philosoph ers ▁such ▁as ▁R agh un ath a ▁Sir oman i ▁( c . ▁ 1 4 6 0 – 1 5 4 0 ) ▁who ▁founded ▁the ▁tradition , ▁Jay ar ama ▁Pan can ana , ▁Mah ade va ▁P un at am ak ara ▁and ▁Y ash ov ij aya ▁( who ▁form ulated ▁a ▁J ain ▁response ). ▁ ▁Orth odox ▁schools ▁The ▁principal ▁Indian ▁philosoph ical ▁schools