The Principle of How Eye Consciousness and Mental Consciousness Discriminate Visible Objects

When the physical eye organ comes into contact with external form objects, it is not the eye faculty itself that actually apprehends the particles of the four great elements from the form objects, but the Tathagatagarbha. The eye faculty is merely like a camera, serving only as a tool or instrument. Utilizing the eye faculty as an instrument, the Tathagatagarbha apprehends the particles of the four great elements from the external form objects. After the Tathagatagarbha apprehends these particles, they pass through the eye faculty, eyeball, vitreous body, and optic nerves to reach the subtle eye faculty (indriya-prasāda) located at the back of the brain. It is directly there that the image of the external form object is formed. Among these, the colors belong to the manifest aspect of form (varna-rūpa), while the mental objects (dharmas) refer to forms included in the realm of dharmas (dharmāyatana-paryāpanna-rūpa). This encompasses shape/form (samsthāna), expressive form (vijñapti-rūpa), and non-expressive form (avijñapti-rūpa). Together, these three constitute the mental object (dharma).

Because color is relatively simple and uncomplicated, the eye consciousness can discriminate it comparatively quickly. In contrast, mental objects are more complex, making them difficult to perceive and clearly identify; therefore, the time required for discrimination is relatively longer. In the first moment (ksana), after the manifest color contacts the eye faculty, the Tathagatagarbha generates the eye consciousness. In the subsequent moment, after the mental faculty (manas) contacts the mental object (dharma), the Tathagatagarbha then generates the mind consciousness (mano-vijñāna). This sequence precisely corresponds to the relationship where the eye consciousness discriminates in the first moment, followed by the mind consciousness discriminating in the second moment. Then, the eye consciousness and mind consciousness jointly discriminate the form object. What is discriminated at this stage is the complete form object (this occurs after the third moment).

Why must the eye consciousness necessarily be generated first in the first moment to discriminate the manifest color, before the mind consciousness can subsequently discriminate the shape/form, expressive form, and non-expressive form? This is because the manifest color must be formed and exist first; only then can it reveal the shape/form, expressive form, and non-expressive form. These three types of form are based on the manifest color. For instance, the size, squareness, roundness, length, and so on within shape/form cannot be represented without the background of the manifest color's hues. Expressive form is manifested based on the manifest color and shape/form, relying on them as its foundation. Non-expressive form is manifested based on the manifest color, shape/form, and expressive form, relying on them as its foundation. Therefore, since the manifest color comes first, the eye consciousness must be generated first to discriminate the manifest color, and the mind consciousness is generated later to discriminate the mental objects.