Bhashya
आत्मा ज्योतिरन्तरं विज्ञानात् ।तदा अनवस्थेति चेत्, न ; ग्राह्यत्वमात्रं हि तद्ग्राहकस्य वस्त्वन्तरत्वे लिङ्गमुक्तं न्यायतः ; न तु एकान्ततो ग्राहकत्वे तद्ग्राहकान्तरास्तित्वे वा कदा- चिदपि लिङ्गं संभवति ; तस्मात् न तदनवस्थाप्रसङ्गः ।विज्ञानस्य व्यतिरिक्तग्राह्यत्वे करणान्तरापेक्षायाम् अनवस्थे- ति चेत्, न, नियमाभावात्— न हि सर्वत्र अयं नियमो भवति; यत्र वस्त्वन्तरेण गृह्यते वस्त्वन्तरम्, तत्र ग्राह्यग्रा- हकव्यतिरिक्तं करणान्तरं स्यादिति नैकान्तेन नियन्तुं शक्यते, वैचित्र्यदर्शनात्; कथम्? घटस्तावत् स्वात्मव्यति- रिक्तेन आत्मना गृह्यते; तत्र प्रदीपादिलोकः ग्राह्यग्राहक- व्यतिरिक्तं करणम्; न हि प्रदीपाद्यालोकः घटांशः चक्षु- रंशो वा ; घटवत् चक्षुर्ग्राह्यत्वेऽपि प्रदीपस्य, चक्षुः प्रदीप- व्यतिरेकेण न बाह्यमालोकस्थानीयं किंचित्करणन्तरमपेक्षते ; तस्मात् नैव नियन्तुं शक्यते— यत्र यत्र व्यतिरिक्तग्राह्यत्वं तत्र तत्र करणान्तरं स्यादेवेति ।तस्मात् विज्ञानस्य व्यति- रिक्तग्राहकग्राह्यत्वे न करणद्वारा अनवस्था, नापि ग्राहकत्व- द्वारा कदाचिदपि उपपादयितुं शक्यते ।तस्मात् सिद्धं वि- ज्ञानव्यतिरिक्तमात्मज्योतिरन्तरमिति ।ननु नास्त्येव बाह्यो- ऽर्थः घटादिः प्रदीपो वा विज्ञानव्यतिरिक्तः ; यद्धि यद्व्य- तिरेकेण नोपलभ्यते, तत् तावन्मात्रं वस्तु दृष्टम्— यथा
In plain words
So this is the answer: the Self is that further light, and it is not the same thing as cognition. But wait — doesn't that set off an infinite chain, one grasper needing another forever? No. Here's why: logic only tells you a grasper must be a separate thing when the object it grasps shows itself as something graspable. But there's no such signal that forces a grasper, just sitting there as a grasper, to always need yet another grasper behind it — that never happens, in any case whatsoever. So the regress you're worried about simply never gets started. But then — what if cognition itself turns out to be something grasped by yet another thing? Doesn't that force us to look for a further tool to do the grasping, and then another, forever? No again, because there's no law saying that has to happen. It isn't true that whenever one thing is grasped by another, a third, separate tool always has to step in. Look at the pot: a cognizer distinct from the pot grasps it, sure, and there a lamp's light really is a separate tool, neither part of the pot nor part of the eye. But now look at the lamp itself: the eye sees the lamp too, just as it sees the pot — yet the eye needs no additional light besides the lamp to do it. So you can't claim, as some fixed law, that being-grasped-by-something-else always drags in one more tool. And that means: even granting that cognition is grasped by something beyond it, no endless chain of tools follows, and no endless chain of graspers follows either. So it's settled — there really is another light, belonging to the Self, distinct from cognition. But now a deeper objection: maybe there's no external world at all, no pot, no lamp, apart from cognition — because, so the argument goes, anything that's never found apart from something else turns out to be nothing more than that other thing. Take, for instance...
Close to the Sanskrit
The Self is another light, distinct from cognition. If it be objected that then an infinite regress follows, the answer is no; for it is stated, according to logical method, that the mere state of being an object of grasping is the mark for its grasper being a distinct entity; but there is never, under any circumstance, a mark by which to establish, as an absolute rule, either that something is merely a grasper, or that a further grasper of that grasper exists; therefore that contingency of infinite regress does not arise. If it be objected that, when cognition is held to be an object graspable by something distinct, there follows a dependence on a further instrument and hence infinite regress, the answer is no, because there is no such rule; for this rule does not hold everywhere. That wherever one thing is grasped by another thing, there a further instrument distinct from the graspable and the grasper must exist — this cannot be laid down as an absolute rule, because a variety of cases is observed. How so? Take the pot: it is grasped, first, by a self distinct from its own being; there, the light of the lamp and the like is the instrument distinct from both the graspable and the grasper. For indeed the light of the lamp is neither a part of the pot nor a part of the eye. Even though the lamp, like the pot, is an object graspable by the eye, the eye, apart from the lamp itself, does not require any further external thing functioning as a light. Therefore it cannot be laid down at all that wherever there is being-graspable-by-something-distinct, there in every case a further instrument must exist. Therefore, in the case of cognition's being an object graspable by a distinct grasper, there is no infinite regress through an instrument, nor can it ever be established through further graspers either. Therefore it is established that there is another light of the Self, distinct from cognition. Objection: But there simply is no external object at all — pot or lamp — distinct from cognition; for whatever is never apprehended apart from something else is observed to be no more than that other thing — for example—