The precise wording is crucial here. It is "the self" - the notion of persistent, continuous "I am" is this "grand illusion". Some ancient Indian and later Tibe

The precise wording is crucial here. It is "the self" - the notion of persistent, continuous "I am" is this "grand illusion". Some ancient Indian and later Tibetan scholars have written about it since 7th century's "doctrine boom" and following "age of the great translation" (of Indian texts into Tibetan language), which resulted in all that plurality of Tibetan sects, while "the realization" of the illusory nature of what we call "I" goes back to the times of Upanishads, long before the Buddha himself. In modern words, what we call "consciousness" is mere a set of processes, which could be switched on and off.)