In this post Shiva Bear investigates the reasons for meditating on the nature of mind by quoting and commenting on the tantras.
The logic in this blog post is tree fold: All of reality purely exists in mind, there are deficiencies arising from not meditating on the true nature of mind and there are in fact benefits of such meditation.
The Vajrapanjara-tantra states:
“Neither ordinary beings nor enlightened ones exist outside of the precious mind”
The meaning of this is that if there were actually phenomena existing outside the mind it would not be possible for us to perceive them in our continuum neither the five senses nor to hold them mentally in our mind. In fact the reason that the awareness can be placed upon an object is due to the existing of the object in mind.
In the Samputa-tantra states:
“All things, external and internal,
Are designated by the mind.
Apart from the mind nothing else exists.”
This reasoning is similar to the thought experiment “if a tree falls in the forest and no one hears it, did it happen” Without the designation of the mind there is no existence of things.
So if phenomena are in fact non-existing and only designated from mind why does it seem to exist for one holding a worldly view (meaning only believing in the things such as they appear to the gross mind)? This is answered by quoting Saraha:
“Even though water is soft
It turns solid like a rock if stirred [constantly] by the wind
An [as] ignorant mind, is stirred by thought,
[it] Turns the formless into a solid entity.”
This however also means that if the diluted mind stops stirring samsara seizes and nirvana naturally appears or as it is stated in the Hevajra-tantra:
“Ignorance gives rise to existential form
Purged of ignorance samsara becomes nirvana.”
As all realities are in fact mind it has many deficiencies not mediating on the true nature of mind itself. It is said the Dharma would be just as effective as a blind man painting if not meditated upon and that wisdom cannot arise without meditation (on tranquility).
To do so however has many benefits and in the Tattva-prakasa sutra it says:
“Meditating for only a day on the meaning of the true nature of things brings greater spiritual benefits than hearing and examining the Dharma for many eons, as it removes the cycle of birth and death”.
The meaning of the quote is that study is worth nothing compared to true experiential insight.
To summarize, all phenomena are mental, not to meditate leads to ignorance while insight gained from meditation leads to enlightenment.