ज्योतिषामपि तज्ज्योतिस्तमसः परमुच्यते।ज्ञानं ज्ञेयं ज्ञानगम्यं हृदि सर्वस्य विष्ठितम्॥
jyotiṣām api taj jyotis tamasaḥ param ucyatejñānaṃ jñeyaṃ jñāna-gamyaṃ hṛdi sarvasya viṣṭhitam
Word by word
The verse says
It is the light of lights, said to be beyond darkness. It is knowledge, and what is to be known, and what knowledge arrives at. It sits in the heart of everyone.
In plain words
Three roles, one subject: the knowing, the thing known, and the arriving.
Which leaves nothing outside — no separate knower who gets there.
And then the last clause, which brings the whole technical chapter home: hṛdi sarvasya viṣṭhitam — seated in the heart of all.
Where you've felt this · in study
A child asks what electricity is and you realise you can describe what it does, measure it, and bill for it, and you cannot say what it is. The lights still work. The not-saying has never once interfered with the using.
Going deeper
Being the knowledge, the known and the reaching all at once removes the last place a seeker could stand.
Every search assumes three things: somebody looking, something looked for, and the distance between. This verse claims all three. There is no arrangement left in which you find it, because finding requires a gap and the gap has been named as the same thing.
That should be frustrating and the last clause is what rescues it.
Seated in the heart of everyone. After eighteen verses of analysis — elements, senses, categories, paradoxes — the chapter puts the whole thing in the one place nobody has to travel to. The technical half of this chapter has been describing something that was never further away than the reader, which is also why none of the technical half was ever going to be enough on its own.