आत्मनः सच्चिदंशश्च बुद्धेर्वृत्तिरिति द्वयम् ।संयोज्य चाविवेकेन जानामीति प्रवर्तते ॥ २५ ॥
In plain words
There are two things here: the being-and-awareness that belongs to the Self, and a passing ripple in the intellect. Non-discrimination splices the two into one — and off goes the thought, "I know."
Close to the Sanskrit
Of the Self, the being-consciousness portion, and of the intellect, the modification — thus the two; and having joined the pair together through non-discrimination, 'I know' comes into operation.