In Hinduism, Adhyasa is imposition of one cognition on the other. It also means false attribution. Adhyaropa is another noun meaning the same – the act of attributing falsely or through mistake. It indicates attributing, through ignorance or through mistake, propertiesof one thing to another: for example, mistaking a rope for a serpent in the dark.
The two words, adhyasa and adhyaropa, are used in Advaita Vedanta to explain the existence of the sole reality of Brahman without any multiplicity or plurality of objects of experience. In reality, the objects have no tangible existence, according to the Vedanta view. They are only appearances, super-imposed on the basic reality of Brahman, due to the veil of maya (ignorance).
Vivarta is another word used to explain the apparent (and not real) nature of objects of experience. Vivarta means an illusory form, an unreal appearance caused by lack of proper comprehension by which the real existent is not comprehended, but in its place, an unreal, imaginary, illusory object is shown by our senses to exist. Thus, the snake is a vivarta of the rope. Similarly, the world of objects of experience is a vivarta of Brahman, which is the reality underlying the variety of objects of experience. This doctrine, namely that only Brahman is real, all else being illusory, is called adhyasavada or adhyaropavada or vivartavada. It is one of the most fundamental doctrines of the Advaita Vedanta school. This extremely idealistic position of the Vedantins regarding the nature of basic reality is opposed by other schools of Hindu philosophy.
Adi Shankaracharya, in his commentary on Upanishads and Brahma Sutras, argues that the dream-objects must be supposed to have some kind of existence while the dream state continues. It is pratibhasika satta. Similarly, the world of daily life also has a kind of existence called vyavaharika satta. When that comes to an end through atmajnana (knowledge of the self), there comes into being paramarthika satta (the transcendental existence) in which the sole reality of Brahman is comprehended. That state is never cancelled by any other state. In that state there is complete negation of adhyasa, adhyaropa or vivarta.