Zen is Buddhism.
Zen views itself as the inheritor of the "true dharma eye," the awakened consciousness of the original Buddha.
Zen believes in the Four Noble Truths
Zen holds to the belief that it is an efficacious method to release the self from the suffering that is caused by desire.
Zen adheres to the Eight Fold Path:
That there is a right view of the world, that right resolve is the way to approach it, that right speech is the way to speak of it, that right conduct leads us through it, that right livelihood sustains us, that right effort produces right results, that right mindfulness guide us, and that the path itself is held together by right "samadhi," meditation on the unity of all things.
Zen contends that its method is useful in the deliverance of people from the vicissitudes of life, and translating the individual to Nirvana.
Zen believes that the Buddha mind can be attained by an individual while within this life, and refers to this state of mind as satori.
Satori is the Zen counterpart of the mystical experience which, wherever it appears, in Zen or any other religion, brings joy, a feeling of oneness with all things and a heightened sense of reality which cannot be adequetly translated into the language of the everyday world. But whereas most religions regard such experiences as the acme of at least the earthly phase of man's religious quest, for Zen it is only the point of departure. In a very real sense, Zen training begins in earnest after the satori has been achieved. For one thing there must be further satoris as the trainee learns to move with greater range and freedom within this noumenal realm. But the important point is that Zen, drawing half its inspiration from the practical, common sense, this-worldly orientation of the Far East to balance the mystical other-worldly half it derived from India, refuses to let man's spirit withdraw-shall we say retreat?-into the mystical state completely. Once we achieve satori, we must get out of the sticky morass in which we have been floundering and return to the unfettered freedom of the open fields.[i]
This is to say that a Zen master would have nothing to do, sitting alone on a mountain top with the experience of the ineffable. In order to give meaning to that experience it is necessary for the enlightened mind to share in the fruits of its discovery.
According to Zen these fruits are peace, and a release from suffering, not just for the individual practicing Zen, but potentially, and ultimately, for everybody.
The Zen "awakening" is not supposed to bring withdrawal from the world. It should rather, Zen claims, encourage participation, though never involvement in the egocentric variety that tends to produce the conflicts and breakdowns so common in modern life.[ii]
The goal of Zen is to produce a sense of peace and oneness, not only for its active practitioners but for the rest of humanity, and indeed the entire living-breathing planet we live on.
Whether Zen is being practiced in a monastery, on a mountain top, or in the everyday life of everyday people, Zen affords those who engage its discipline, freedom from the confusion of paradox, the pain of conflicting desires, and the disorientation of feeling isolated and alone in a seemingly disparate, disconnected and circumscribed universe.
Zen sees all things as a unity in which any thing may manifest the reality of the whole, it views the whole as not being greater than the sum of its parts, indeed it views the whole as not even being greater than even its most minuscule part. Zen sees the perfect image of the whole contained within the part.
There is wisdom in Zen.
When its contemplative methods are dissociated from the particular institution of Buddhism the application is universal in scope, and reveals the essence of the “true dharma eye” that the original Buddha possessed.
All religions can benefit from the wisdom of Zen, to free them from the conflict that arise out of cultic ritual, and doctrinal investments, from particularism, tribalism, and wrenching demands of dogma.
The Perfect Way knows no difficulties
Except that it refuses to make preference
Only when freed from hate and love
It reveals itself fully and without disguise
A tenth of an inch's difference
And heaven and earth are set apart
If you want to see it manifest
Take no thoughts either for or against it
To set up what you like against what you dislike
That is the disease of the mind
When the deep meaning [of the way] is not understood
Peace of mind is disturbed and nothing is gained
[The Way] is perfect like unto vast space
With nothing wanting, nothing superfluous
It is indeed, do to making choices
That its suchness is lost sight of
When the mind rests supreme in the oneness of things
Dualism vanishes by itself
-beginning of the Hsin-hsin-ming by Seng-ts'an
as translated by D. T. Suzuki, Essays in Zen Buddhism, First Series
On Zen Buddhism