因明入正理論疏 3.82

3.82

所依不成者，且約依宗，為喻所依。如數論師對佛法者立眼等根為神我受用，同喻如色等。此即能別不極成故，喻無所立，亦無所依。由無所依，喻上所立亦不得成。有云：既有能立，故無第四，若二立無，豈無此過？

As for unestablished substratum (āśrayāsiddha): provisionally in terms of relying on the thesis as the substratum of the example: for instance, a Sāṃkhya master establishes against a Buddhist that the eye and other sense faculties are experienced by the spiritual self (puruṣa), with the similar example being like form and the like. This is because the qualificand is not mutually established, so the example lacks the probandum and also lacks a substratum. Due to lacking a substratum, the probandum on the example also cannot be established. Some say: 'Since there is a means of proof, there is no fourth fallacy; but if both probandum and means of proof are absent, how could there not be this fallacy?'