The Mind Base is the Concomitant Condition of Consciousness

Concomitant dependence: "Concomitant" means two or more dharmas coexisting together; "concomitant" implies being inherently together from birth, present at the moment of arising. "Dependence" refers to reliance, where the existence of this necessitates the existence of that—this dharma relies on that dharma to arise and exist.

Some claim that the five sense faculties are the concomitant dependence of consciousness, meaning the five sense faculties are the necessary condition for the arising of consciousness: without the five sense faculties, there is no consciousness; the presence of consciousness necessitates the five sense faculties. But is this truly the case? Considering the forms of sentient beings, many beings lack the five sense faculties yet still possess consciousness. For instance, formless realm devas, or bodhisattvas and great arhats manifesting without physical bodies, all possess consciousness yet lack the five sense faculties. The isolated consciousness of all sentient beings does not rely on the five sense faculties to arise or exist. In profound meditative concentration, when consciousness extends beyond the body, it can still perceive sensory objects without requiring the five sense faculties. Therefore, the five sense faculties are not the concomitant dependence of consciousness. The concomitant dependence of consciousness is the eighth consciousness, the mental faculty, and the seeds.

The conditions required for the arising of consciousness are very few, thus it arises easily and ceases easily. The five consciousnesses cease entirely and do not exist in the concentrations above the second dhyāna. Consciousness ceases only in the state of non-perception and the cessation attainment. Therefore, it is said that the concomitant dependence of consciousness is not the five sense faculties nor the five consciousnesses, but the mental faculty. The mental faculty is the root from which consciousness can arise; consciousness relies on the mental faculty to arise and function. Only after the mental faculty performs mental engagement and makes choices can consciousness arise; otherwise, it cannot. Thus, consciousness is always accompanied by the mental faculty, serves the mental faculty, regulates and perfumes the mental faculty. However, the mental faculty does not necessarily accompany consciousness; it does not necessarily coexist with consciousness. There are many instances when the mental faculty exists alone, such as during sleep.