The Mandukya Upanishad
With an Advaita Commentary from our Understanding
61. As in dream, the mind through Maya moves, having or, presenting the appearance of the dual (grahya and grahaka), so in the waking state, the mind through Maya moves, having or, presenting the appearance of the dual.
Again the dream state is our useful object of reference. Here the mind gives the impression of movement and duality of things.
This illusion or play or Maya is just as functional and gives just as much reality in the waking state as in the dream state is the statement here.