Yogācārabhūmi-śāstra (Volume XI)

The encounter of different conditions refers to: when conditioned by contact with pleasant feeling, one encounters contact with painful feeling while experiencing pleasant feeling; when conditioned by contact with painful feeling, one encounters contact with pleasant feeling while experiencing painful feeling; when conditioned by contact with neutral feeling, one encounters contact with either pleasant or painful feeling while experiencing neutral feeling. Furthermore, a person with greed encounters conditions for hatred; when the afflictive bonds of greed cease, the afflictive bonds of hatred arise. Similarly, a person with hatred and delusion encounters conditions for the arising of afflictions belonging to different categories. Likewise, when eye-consciousness is presently manifesting, it encounters objects such as sound, smell, taste, and tangible contact. These are called the eight kinds of causes and conditions for change. All changes in material and immaterial phenomena arise solely from these eight kinds of causes and conditions. Beyond these, there are neither any that exceed them nor any that are additional.

Explanation: The meaning of "encounter of different conditions" is: conditioned by contact with pleasant feeling, one should experience pleasant feeling, but instead encounters contact with painful feeling; conditioned by contact with painful feeling, one should experience painful feeling, but instead encounters contact with pleasant feeling; conditioned by contact with neutral feeling, one should experience neutral feeling, but instead encounters contact with pleasant feeling or painful feeling. Additionally, a greedy person encounters conditions for hatred; here the afflictive bonds of greed cease, but there the afflictive bonds of hatred arise. Similarly, a person with hatred and delusion encounters conditions for the arising of afflictions not belonging to hatred or delusion, and it is likewise. Similarly, when eye-consciousness is presently manifesting, it encounters objects such as sound, smell, taste, and tangible contact. These are called the eight kinds of causes and conditions for change. All changes in material phenomena and immaterial phenomena arise entirely from these eight kinds of causes and conditions. Beyond these, there are no other causes or conditions.

Here, "different" means change. When the encountered conditions change, and the cause changes, the effect accordingly changes. Changes in causes and conditions are broadly categorized into these eight kinds; finer distinctions may be numerous. Because conditions can change, they are impermanent. Because effects can change, they are also impermanent. Through changes in causes and conditions, impermanence is fully and completely revealed.