Mandukya Karika, verse 2.4

Text

अन्तःस्थानात्तु भेदानां तस्माज्जागरिते स्मृतम् ।
यथा तत्र तथा स्वप्ने संवृतत्वेन भिद्यते ॥ ४ ॥

antaḥsthānāttu bhedānāṃ tasmājjāgarite smṛtam |
yathā tatra tathā svapne saṃvṛtatvena bhidyate || 4 ||

4. Different objects cognized in dream (are illusory) on account of their being perceived to exist. For the same reason, the objects seen in the waking state are illusory. The nature of objects is the same in the waking state and dream. The only difference is the limitation of space (associated with dream objects).

Shankara Bhashya (commentary)

The proposition to be established (Pratijñā) is the illusoriness of objects that are perceived in the waking state. “Being perceived” is the “ground” (hetu) for the inference. They are like the objects that are perceived in dream, is the illustration (dṛṣṭāntaḥ). As the objects perceived to exist in dream are illusory so also are the objects perceived in the waking state. The common feature of “being perceived” is the relation (Upanaya) between the illustration given and the proposition taken for consideration. Therefore the illusoriness is admitted of objects that are perceived to exist in the waking state. This is what is known as the reiteration (Nigamanam) of the proposition or the conclusion. The objects perceived to exist in the dream are different1 from those perceived in the waking state in respect of their being perceived in a limited space within the body. The fact of being seen and the (consequent) illusoriness are common to both.