How to Use the Cognitive Nature of the Conscious Mind to Undertake Chan Investigation

Some people say that the knowing of the seventh consciousness is the Buddha-nature. Such a view fails to distinguish the true from the deluded, and fundamentally does not understand the wondrous function of the Buddha-nature. Although the seventh consciousness also has knowing, the knowing of the seventh consciousness and the seeing-nature of the Buddha-nature are two different functions; they are not the same thing. Although the Buddha-nature does not exist or manifest apart from the seventh consciousness, the knowing of the seventh consciousness differs vastly in its content from the Buddha-nature. The seventh consciousness is the function arising from the element of consciousness within the eighth consciousness, while the Buddha-nature is the function arising from the element of seeing within the eighth consciousness. The element of seeing spoken of in the Śūraṅgama Sūtra is precisely the Buddha-nature. The Buddha-nature does not require one to contemplate it too clearly, nor does it require deep investigation; when it is too clear, yet merit and meditative concentration are insufficient, seeing the Buddha-nature becomes very difficult.

After seeing one's true mind, cultivate dhyāna and merit well; when both are complete, then investigate the Buddha-nature, and there will be an opportunity to see the Buddha-nature. If even one condition is lacking, there is no hope of seeing the nature. Therefore, when the conditions are not ripe, do not deeply probe the content of the Buddha-nature; instead, cultivate more merit and more meditative concentration. When preparatory concentration (anāgamya-samādhi) is very deep, then carefully and subtly investigate the Buddha-nature; at that time there will be the opportunity to see the nature.

What dharmas does the seventh consciousness know? Because the seventh consciousness has a faint discerning wisdom, the seventh consciousness knows the mental-object realms of the six sense objects, and knows all the mental-object appearances manifested by the eighth consciousness, but it only knows them in a coarse way, without knowing the details and specific contents. Whatever the eighth consciousness manifests, the seventh consciousness takes as its object; whatever it takes as its object, it knows. But that knowing cannot know what the specific mental objects are; it can only know a rough outline.

The knowing we use in investigating Chan is, on the surface and in the early stage, still dominated by the knowing of the sixth consciousness; but in the later stage and at deeper levels of investigating Chan, the manas—the seventh consciousness—takes the lead, with the sixth consciousness assisting the seventh consciousness by providing relevant and necessary theoretical bases, so that the seventh consciousness can deliberate (manana) and make decisions in a deep and subtle way. However, the knowing nature of the sixth consciousness has never departed from the knowing of the seventh consciousness; the seventh consciousness has always been operating deeply and subtly, which is what enables the sixth consciousness to have its nature of discrimination and discernment. Investigating Chan mainly uses the mind consciousness to investigate. Using this knowing nature of the mind consciousness, cultivate this knowing well, and at every moment carry the thought of this knowing, suspending it in the mind of the manas; then transform this thought into a huatou, and one can investigate Chan—very quickly. Once the knowing thought is transformed, it becomes the thought of investigating Chan. Take the thought that constantly knows all dharmas, exchange it for a huatou, exchange it for a gong'an, exchange it for the content of a certain dharma, and one can investigate; one day one will be able to attain realization and enlightenment.