The emptiness section of the Three Principal Aspects of the Path takes us through a series of five meditations we can do with respect to any phenomena. To illustrate, I will use the self-generation of ourself as the deity:
1. Meditate on non-dual appearance and emptiness. We can do this by meditating on the four profundities. To meditate on the first two profundities, we think the self-generation we normally see does not, but the self-generation does appear, exist and function. To meditate on the second the second two profundities, we specifically meditate on non-dual appearance and emptiness. The self-generation is not other than emptiness, emptiness appears as the self-generation.
2. Meditate on dependent relationship. This has four levels: the self-generation arises in dependence upon causes and conditions, such as having received an empowerment; listened to, contemplated, and meditated upon correct instructions; and engaged in the mental actions of generating the mandala. It exists in dependence upon its parts, such as the charnel grounds, Mount Meru, the Celestial Mansion, the five wheels of deities, etc. The parts can also be divided into what appears – the mandala, what is understood – its emptiness, what is experienced – great bliss, what it is held by – our mind; and what is known – ourself as the deity. It also exists in dependence upon its basis of imputation, namely the collection of the parts, but the phenomena itself is not its basis of imputation. We make a distinction between the basis of imputation and the imputation and the imputation itself. It finally exists in dependence upon its mere name – Heruka is what we call ourself generated as the deity. At a more profound level the Dharmakaya in the aspect of the basis of imputation makes the expressive sound Heruka. It is the Dharmakaya speaking that is the mere name. The sign we have done this correctly is our self-grasping reduces or ceases, but our divine pride increases.
3. Meditate on negating the two extremes in a special way. We negate the extreme of existence by realizing it exists as a subtle dependent relationship, a mere name. The extreme of existence says if things exist, they must exist inherently. By seeing how something can exist as mere name/appearance, we realize how it doesn’t have to exist inherently to exist. We negate the extreme of non-existence by realizing when we see the self-generation we normally see does not exist, we are not left with nothing, we are left with a non-dual appearance of the self-generation and its emptiness. The extreme of non-existence says if things do not exist inherently, they do not exist at all. No, we can strip away the mistaken appearance and conception of inherent existence and something remains, namely the non-dual appearance and emptiness of the supported and supporting mandala.
4. Meditate on non-dual karma and emptiness. The self-generation arises from karma but there is no karma other than emptiness. The laws of karma describe how the emptiness of our person shape-shifts from a samsaric being into the self-generation (changing the basis of imputation of our I). The laws of karma are like the laws of fluid dynamics that explain how emptiness shape-shifts appearance. In economics, we make a distinction between static and dynamic analysis. Static analysis is how things appear in a snapshot of time, dynamic analysis explains how things change over time. Non-dual appearance and emptiness is static analysis, non-dual karma and emptiness is dynamic analysis. Each of the four main aspects of karma (ripened effect, environmental effect, tendency similar to the cause, and effect similar to the cause) are the laws governing this motion of the ocean of non-dual appearance and emptiness. Interestingly, when you look at the actual laws of fluid dynamics, you see these four effects.
5. Meditate on the non-dual bliss and emptiness (Tantra Prasangika view). This is not explicitly mentioned in the Three Principal Aspects of the Path, but since the uncommon characteristic of Je Tsongkhapa’s doctrine is the union of sutra and tantra, I would say it is implied. The Tantra Prasangika view combines the Prasangika view that all phenomena lack inherent existence with the Chittamatrin view that all phenomena are by nature our mind, while recognizing that our very subtle mind itself is the nature of great bliss. In the context of the self-generation meditation, what appears is the self-generation of ourself as the deity, what is understood is its emptiness, what is experienced is great bliss, all this is known/held/by nature our very subtle mind of great bliss. The emptiness of our very subtle mind of great bliss appears in the aspect of the self-generation. This object is non-dual with the subject mind of great bliss – they are two aspects of the same phenomena, like the gold and its coin.
We can do these same five meditations with any phenomena. This is how we cut the root of samsara. In this way, we realize the emptiness of samsara and nirvana. On the basis of these understandings, we can then reshape emptiness from samsara and its inhabitants into a pure land and all the deities.