Theoretical Knowledge and Views, Intellectual Realization, and Experiential Realization Are Three Levels.

Merely knowing that the five-aggregate body is generated by the eighth consciousness is basic Mahāyāna theoretical knowledge and view; one has only just taken the first steps on the Mahāyāna path, and there is still a distance from direct realization. As for how great that distance is, it varies from person to person. At the time of direct realization, one must be able to observe specifically where the eighth consciousness is functioning and what function it performs. If it is merely theoretical knowledge and view, then it has nothing whatsoever to do with resolving the problem of birth and death. Some people consider this to be understanding through intellect, but in fact it does not even amount to that. Knowing that all dharmas are the function of the eighth consciousness—this knowledge and view is still rather shallow; saying it day after day is merely "Chan of the mouth," and it may not be of much use for actual realization. But this is the foundation of learning Buddhism; from this knowledge and view, one will gradually merge into the eighth consciousness.