Sat-darshana Bhashya (translation)

Verse 28.

भावेऽहमः सर्वमिदं विभाति
लयेऽहमो नैव विभाति किञ्चित् ।
तस्मादहरूपमिदं समस्तं
तन्मार्गणं सर्वजयाय मार्गः॥

With the ego-self rising, all appear. On its setting, they disappear. Hence is all this but the ego’s form. The quest for it is the way to conquest.

So much has been said of the ego, its character and origin, its pose and play that we are now in a position to appreciate the truth of the statement "The ego rising, all rises.’ But it should not be misunderstood that the world, whatever its real character, depends for its existence upon my ego or any other ego. It only means that the world as it presents itself to my ego-sense, that is, as a separate independent existence manifest in qualities and quantities, ceases to do so in the absence of a consciousness formed as the ego which uses the world of appearance as a suggestion from which it draws out its forms in qualities and quantities, in which it revels. If this ego is merged or outlived, the world of forms as we have it vanishes and in its place the world of Reality (vide verse 20) presents itself to the surviving persisting, supreme consciousness of the Self which is not the ego. Hence to search for the ego and conquer it (by abandoning it) is the indispensable condition for the conquest, and possession of the All-and this involves a control over the appearances that screen the Truth, the Real Self from the external and surface being, (cf. verses 5 and 6.)

Nishtha the supreme poise of the Self results from the merging of the ego implemented by an earnest quest.