The master is unable to express in words what the student wants to hear because the student needs to experience it for himself, and not be told directly how to gain it. .
The concept of "emptiness" is a perfect reason why Chan Buddhism is unable to be said or written in words. Emptiness is the belief that everything in nature is empty inside, and therefore, has no identity. Whenever one gives a name to something, he is giving that object an identity, but according to the emptiness of objects, it should not have an identity. The use of language is a dualistic thought, contradicting the non-dualistic ideals of Chan Buddhism. When Shih-t'ou proclaims, "do away with your throat and lips," (Foster, 40) he means that Ta-tien should not try to give objects an identity by using language because language is an obstacle to reaching nirvana. When Ta-tien has nothing left to say he "may enter the gate" (Foster, 40) to reach enlightenment; he has accepted the "experience beyond words." When there is no longer the need to use words to give identities to objects in the world, then the act of meditation can then be perfected. Everything has a complement and/or contradiction in which both of those entities exist. Things always exist relative to other things. To perceive emptiness, one must be aware of how the mind "constructs" attachments and fears. We "construct" and categorize our attachments and fears by using language, when in fact we should not because things are neither substantially existent nor absolutely non-existent, so we cannot give them an identity. .
The mind-only aspect of early Buddhism is perhaps the most related to the practice of an unexplainable, and indescribable experience. The mind divides things into object versus subject, self versus other, etc. Zen is influenced by mind-only, as it is the driving force to meditation. Meditation is the search for the inner-peace in one's mind, while at the same time trying to obtain that sudden enlightenment all Buddhists strive for.