The 25 Sloka compacting of the MahaPrajñāpāramithā is the Hridaya Sūtra [‘Heart Sūtra’] the daily invocation in every Zendo. Intentionally bite-sized, it is to be read and interpreted only as supplement to the Vajrachedika for its very tight phrasing can seriously miscue the entrant. Given its brevity it is laid-out in its entirety at the link below.
No Sūtra in the entire canon is more direct, in-your-face, unflinching in its declaration than the Heart Sūtra. And very few Sūtras have been more insistently spun into a mystic outer-space than the Heart Sūtra.
The key line in the Sutra is: ‘The Prajñā-pāramithā mantra is said in this way: Om Gatheh! Gatheh! ParaGatheh! ParasamGatheh! Bodhi Svaha!’ [My understanding, released, soars, takes flight. Svaha!].
The summary expression has identical meaning to what is referred to on this Site as: ‘The natural and proper ‘Divide’ is as ‘True Nothing’ and ‘Not-True Nothing’. The leap from the limit of abstraction, the final Binary.
But its interpreters, certainly the contemporary ones, never got there. Why was that? The descent begins with the replacement of this cryptic line with a more comprehensible one, a line marking approach: ‘Form is emptiness; emptiness also is form. Emptiness is no other than form; form is no other than emptiness.‘ [I won’t quibble with the translation but the original preferred the link ‘Not different from’, a meaningful distinction].
I’ll briefly go over the details.
Shūnyam is the formal Sanskrit for Śūnya in common-speak. Etymologically, Shūnyam originate in the notion of hollowness, of ‘Empty Inside’.
The term ‘Empty’ or ‘Null’ as used in English translations of Shūnyam originate directly from the vocabulary of Classical Logic as does the word ‘Form’ as used in the Heart Sutra. [Although no guru, fee-speaker or book-writer I have met is aware of this root, which might explain their wildly creative interpretations of these two terms.]
Shūnyam itself is not to be confounded with the numerous versions of Śūnya with a suffix that evolved in the regional Dharmic literatures well into the 10th Century [ŚūnyaBrahman, ŚūnyaPurusha et al]. Or the selective use of the term ‘Emptiness’ in others [Kashmiri Shaivism, the Southern Bhairava et al]
The later derivative construct of Shūnyathā, a pivotal term in the ‘Heart Sūtra’ found its inspiration in an established earlier earlier divide: Táthātā and Tát. And as with Shūnya, there are a variety of definitions of Shūnyathā to pick from beginning with the Theravada and reaching into all variants of the Mahayana.
What’s the difference? Táthātā, typically translated into English as ‘That-ness’ [also as Suchness, Thusness] is the abstraction of Tát [‘That’]. The problem is that you cannot abstract ‘That’ which has already gone well beyond such distinctions as ‘Abstract and Concrete’. It can only be abstracted by one who doesn’t understand its intent.
If it had any other purpose it was to differentiate the philosophical substance of ‘That’ from its routine grammatical chores. This would have been entirely legitimate. But it was rarely used in this service and very soon after its construction [and predictably so], it took on a philosophical life of its own.
What happened with Tát: Táthātā is exactly what happened much later in the construction of the distinction: Shūnyam: Shūnyathā.
Again and as before, one does not abstract ‘True Nothing’. Shūnyam itself is the leap from the limit of abstraction. It is ‘abstracted’ only by one who does not comprehend its intent or meaning.
[But the derivative extension of Shūnyathā continued to firmly retain the original Logical Form of its parent. Its most consistent definition in the higher texts has been ShūnyathāShūnyathā: ‘The Emptiness of Emptiness itself’, a full-blown Self-Eating Expression.]
The result was hugely consequential. Depending on the source, Shūnyathā has been interpreted both as a synonym for a conceptualized Shūnyam and otherwise as a mystic expression for some special capture of Awareness, Consciousness, or the Whole.
This is continued in the Post: Emptiness And ‘Form’: Self-Reference
Without getting into the details here, the later extensions, principally the Madhyamaka, pivot off the Principle Of Co-Dependence without reaching into the Axioms of Sight and ‘Self”, in parallel to the Vedanthic stop at ‘Being: Consciousness’.