How to Use the Knowing Nature of the Conscious Mind to Investigate

Some people say that the knowing of the seventh consciousness (manas) is the Buddha-nature. This view fails to distinguish the true from the false 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-and-awareness nature of the Buddha-nature are two different functions and are not the same thing. Although the Buddha-nature does not exist apart from the seventh consciousness and does not manifest apart from it, the content of the seventh consciousness's knowing differs vastly from the Buddha-nature. The seventh consciousness is the function arising from the element of consciousness within the eighth consciousness (Ālayavijñāna), while the Buddha-nature is the function arising from the element of seeing within the eighth consciousness. The element of seeing discussed in the Śūraṅgama Sūtra is precisely the Buddha-nature. The Buddha-nature does not need to be contemplated too clearly, nor does it need to be investigated too deeply; when it is too clear, if merit and meditative concentration are not yet sufficient, seeing the Buddha-nature becomes very difficult.

After seeing the mind, cultivate meditative concentration and merit well; when both are sufficient, 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 investigate the content of the Buddha-nature; instead, one should cultivate more merit and more meditative concentration. When the preparatory concentration (anāgamya-samādhi) is very deep, then carefully and subtly investigate the Buddha-nature; at that time there will be an opportunity to see the nature.

What dharmas does the seventh consciousness know? Because the seventh consciousness has a weak discriminating wisdom, the seventh consciousness knows the dharma-realm of the six sense objects, knowing all the dharma-object marks manifested by the eighth consciousness, but it only knows them in a rough outline, not 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 dharma-objects are; it can only know a general outline.

The knowing we use in investigating Chan is, on the surface and in the early stages, still primarily the knowing of the mind consciousness (the sixth consciousness); but in the later stages and deeper levels of investigating Chan, it is primarily the manas, the seventh consciousness, with the sixth consciousness cooperating with the seventh consciousness, providing relevant and necessary theoretical bases, so that the seventh consciousness can deliberate (manasikāra) 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 been operating deeply and subtly all along, and only then can the sixth consciousness 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, moment by moment carrying the thought of this knowing, suspending it in the mind of the manas, and then converting this thought into a huatou (critical phrase)—then one can investigate Chan, and very quickly. Once the knowing-thought is converted, it becomes the thought of investigating Chan. Take the thought that constantly knows all dharmas and replace it with a huatou, replace it with a gong'an (public case), replace it with the content of a certain dharma—then one can investigate, and one day one will be able to attain realization and enlightenment.