he tried to show that the concomitance is not between those cases which possess the li@nga or reason with the cases which possess the sâdhya (probandum) but between that which has the characteristics of the li@nga with that which has the characteristics of the sâdhya (probandum); or in other words the concomitance is not between the places containing the smoke such as kitchen, etc., and the places containing fire but between that which has the characteristic of the li@nga, viz. the smoke, and that which has the characteristic of the sâdhya, viz. the fire. This view of the nature of concomitance is known as inner concomitance (_antarvyâpti_), whereas the former, viz. the concomitance between the thing possessing li@nga and that possessing sâdhya, is known as outer concomitance (_bahirvyâpti_) and generally accepted by the Nyâya school of thought. This antarvyâpti doctrine of concomitance is indeed a later Buddhist doctrine. It may not be out of place here to remark that evidences of some form of Buddhist logic probably go back at least as early as the _Kathâvatthu_ (200 B.C.). Thus Aung on the evidence of the _Yamaka_ points out that Buddhist logic at the time of As'oka "was conversant with the distribution of terms" and the process of conversion. He further points out that the logical premisses such as the udâhara@na (_Yo yo aggimâ so so dhûmavâ_--whatever is fiery is smoky), the upanayana (_ayam pabbato dhûmavâ_--this hill is smoky) and the niggama (_tasmâdayam aggimâ_--therefore that is fiery) were also known. (Aung further sums up the method of the arguments which are found in the _Kathâvatthu_ as follows: "Adherent. Is _A B_? (_@thâpanâ_). Opponent. Yes. Adherent. Is _C D_? (_pâpanâ_). Opponent. No. Adherent. But if _A_ be _B_ then (you should have said) _C_ is _D_. That _B_ can be affirmed of _A_ but _D_ of _C_ is false. Hence your first answer is refuted.") The antecedent of the hypothetical major premiss is termed @thâpanâ, because the opponent's position, _A_ is _B_, is conditionally established for the purpose of refutation. The consequent of the hypothetical major premiss is termed pâpanâ because it is got from the antecedent. And the conclusion 158 is termed ropa@na because the regulation is placed on the opponent. Next: "If _D_ be derived of _C_. Then _B_ should have been derived of _A_. But you affirmed _B_ of _A_. (therefore) That _B_ can be affirmed of _A_ but not of _D_ or _C_ is wrong." This is the pa@tiloma, inverse or indirect method, as contrasted with the former or direct method, anuloma. In both methods the consequent is derived. But if we reverse the hypothetical major in the latter method we get "If _A_ is _B_ _C_ is _D_. But _A_ is _B_. Therefore _C_ is _D_. By this indirect method the opponent's second answer is reestablished [Footnote ref 1]." The Doctrine of Momentariness.