These explanations are in accord with the Great Symbol Thig-le[r_nar:72]. Each of the four down-coming and up-going Blisses can be divided into four, making the so-called sixteen portions of the Moon-Elements. Following the viewpoint of the Sun, each bliss can be divided into three, making the total of twelve.

The [above] Tantra says:

"The signs of hare and so forth
Are the Thig-le of sixteen-fold bliss.
They are the substance of the A-li [the vowels].
The four Wheels come in order.
Following these different sayings,
They can be understood as twelve Sun-Elements."

When the Bodhi-Heart goes upward or downward, the blood element always goes with it. As it reaches the four respective centers in each level of each center, a specific Bliss is experienced, making a total of sixteen. From the viewpoint of the intensiveness of the Bliss, the Bliss of each center can be divided into three--the Extreme Bliss,

the Medium Bliss, and the Small Bliss--making a total of twelve. The experienced yogi should know the subtle differences between these. [**]

The four up-going Blisses should be much stronger than the down-coming Blisses. In the up-going process, until the reversed operation has become steady, the Bliss will not be steady at the Head Center. When the Head Center becomes steady, the Bliss will also be steady. Says the [same] Tantra [ibid.]:

"Upon the life is the mind;
Because of the reversal it flows,
Dwells in the center of the lotus's navel;
Thereafter, it will stabilize.
At that time the refuge will not go away.
As in a utensil without any hole,
The water in it will never be exhausted.
That is the time the bliss will become steady.
The Innate-Bliss (comes) from the stabilization,
Thus, the nerve-ending Buddha is accomplished
Through this way, the yogi attains his conviction."

The mind means the secretion (or drops). Reversal means reversing the process of the ordinary route. Stabilization means the head. These explanations are given in the Mang-snag, the intimate pith-instruction.

There are a great many pith-instructions. According to one of them when the warmness becomes stabilized, the

[paragraph continues] Bodhi-Heart in the nerve begins to melt; because of the melting of Bodhi-Heart the Bliss arises. When the Bliss becomes steady, the Non-Discrimination (Wisdom) arises. This explanation is very general; it does not give the specific explanations on the up-going and the down-coming Blisses. Nor does it make clear the recognition of the great Innate Bliss. In view of this, I have given the explanations of the Four Blisses in two categories, as stated in the Tantras and instructed by the great accomplished yogis.