坐禪三昧經 2.23

2.23

當知心受苦樂、受不苦不樂。云何心？是心無常，從因緣生故。生滅不住，相似生故，但顛倒故，謂是為一。本無今有，已有還無，是故無常。觀知心空。云何為空？從因緣生，有眼有色，可見憶念，欲見如是等，和合眼識生。如日愛珠，有日有珠，有乾草牛屎，眾緣和合，於是火生。一一推求，火不可得，緣合有火。眼識亦爾，不住眼中，亦非色中住，不兩中間住，無有住處，亦復不無。是故佛言：「如幻如化」。現在心觀過去心，或苦、或樂、或不苦不樂，心各各異各各滅，有欲心、無欲心亦如是，各各異各各滅，觀內心、觀外心、觀內外心亦如是。是名心念止。

One should know that the mind experiences suffering and pleasure, and experiences neither suffering nor pleasure. What is the mind? This mind is anitya, because it is born of causes and conditions. Arising and perishing without remaining, arising in similarity, only because of viparyāsa does one regard it as single. Originally non-existent and now existing, having existed and returning to non-existence, it is therefore anitya. One contemplates and knows the mind is empty. How is it empty? Born of causes and conditions: there is the eye and there is form, what can be seen and mindfulness, the desire to see, and so forth—in harmony, eye-consciousness arises. Just as with a sunstone, where there is the sun, the stone, dry grass, and cow dung, and when these many conditions come together, fire is produced from them. Searching each one individually, fire cannot be found; only when conditions combine is there fire. Eye-consciousness is also like this: it does not abide in the eye, nor does it abide in form, nor does it abide between the two; it has no place of abiding, yet it is also not non-existent. For this reason the Buddha said: 'Like an illusion, like a phantom.' The present mind contemplates the past mind as either suffering, or pleasure, or neither suffering nor pleasure; the minds are each distinct and each perishes. A mind with desire and a mind without desire are also like this: each distinct and each perishes. Contemplating the internal mind, contemplating the external mind, and contemplating the internal and external mind are also like this. This is called mindfulness of the mind.