[Image] Edward Conze was of the opinion that the oldest layer of the Prajñāpāramitā textual tradition is probably the  first two chapters of the Ratnaguṇasaṃcayagāthā (Rgs). He sees it as closely related to the Aṣṭasāhasrikā Prajñāpāramitā Sūtra (8000 line Perfection of Wisdom Text; Aṣṭa) but conjectures that verse precedes prose. Other scholars have conjectured that the verse is actually a post hoc summary of the prose. At present there is insufficient information to decide one way or the other. In some manuscripts the Rgs is included as a chapter of a larger Prajñāpāramitā text (8k and 100k), inevitably numbered "chapter 84".

While we don't have very old manuscripts of the Rgs, we do have one of the Aṣṭa in Prakrit from the 1st Century (carbon dated to between 47 and 147 CE) and thus probably from the end of the 1st Century CE. We also have a very early (179 CE) Chinese translation by the Scythian translator, Lokakṣema. We now know that the Aṣṭa was composed in Prakrit in Gandhāra which solves some of the existing problems of where to locate the early Prajñāpāramitā tradition. Rgs by contrast was not translated in Chinese until the 10th century by Faxian 法賢 (991CE), 《佛母寶德藏般若波羅蜜經》Fúmǔ-bǎodécáng-bōrěbōluómì(duo)-Jīng (T 229). This means that it played no part in the understanding and development of Perfection of Wisdom thought in China. This Chinese version is, according to Yuyama (1976), probably the most corrupt of all the versions. It is closer to Recension A, but still very different in many places. This may be due to Faxian's "free (or perhaps bad) translation." (xl)
As we now know, the Heart Sutra or Hṛdayaprajñāpāramitā is mostly comprised of some quotes from a Chinese Large Perfection of Wisdom Text equivalent to the Sanskrit Pañcaviṃśatisāhasrikā Prajñāpāramitā Sūtra. The most likely candidate is Kumārajīva's translation 《摩訶般若波羅蜜經》Móhēbōrěbōluómì Jīng by Kumārajīva (T 223; 404 CE). We also know that the larger texts in 18,000, 25,000 and 100,000 lines are simply an expansion of the Aṣṭa. It is possible to trace many of the cited passages from the Hṛdaya back into the Pañcaviṃśati; but we ought to be able to go one step further and trace some of them back into the Aṣṭa and Rgs. This essay will revisit an aspect of the roots of the Hṛdaya in the Prajñāpāramitā literature, particularly for the epithets passage:
Tasmāj jñātavyam prajñāpāramitā mahāvidyā anuttaravidyā 'samasamavidyā. 
In Jan Nattier's watershed article (1992) she notes a few examples of this genealogical approach with respect to the epithets passage. Nattier, in note 54a, explains that the epithets are epithets of prajñāpāramitā itself and that the word mantra is an erroneous back translation of 明咒 míng zhòu (= vidyā), with confusion arising because 咒 zhòu is used in the same capacity and even appears alongside 明咒. I conjecture that the confusion was exacerbated because the composition of the early Prajñāpāramitā texts occurred well before Tantric Buddhism, while the translation of the Hṛdaya from Chinese into Sanskrit occurred post-tantra and the reading of 咒 was.

An interesting comparison is with the six-syllable mantra: oṃ maṇipadme hūṃ. Alex Studholm's study of the Kāraṇḍavyūha Sūtra (Kvs) reveals the early history of this mantra. I've written two previous essays on Studholm's conclusions:
The origins of oṃ maṇipadme hūṃ. The Meaning of oṃ maṇipadme hūṃ. Throughout the Kvs the "mantra" is never referred to as a mantra, but only and always as the ṣaḍakṣarī mahāvidyā (61) "the six-syllabled great techne". Vidyā is a difficult word to find a good English translation for in this context. Techne is a Greek word which has almost exactly the same range of meaning, i.e. 'art, craft, skill', and is the source of our word technology. I'm trying it out in this essay, but I wouldn't insist on it. My only stipulation would be that we cannot translate vidyā as "science" because it is anachronistic. The word "science" properly applies to the systematic empirically based descriptions of the world, tested through conjecture and refutation, which began in the late 15th century in Europe. There is an archaic use of the word science which does cross over with vidyā, but it is archaic. And in the present there is too much confusion over the distinctions between science and religion to be slack in how we use the words. Better a neologism than an anachronism if we communicating to a present day audience. Indeed if anything the argument ought to go the other way. We might, as some do, translate vidyā as 'spell' or 'magic'. The main idea here is the specialist knowledge of Buddhist practices which allow us to gain first-hand, experiential knowledge of how the perceptual situation creates duḥkha. This has a magical flavour in many texts, and can result in extra-sensory perceptions, but there is nothing of science here. Vidyā is religious knowledge.

As we know, mahāvidyā is one of the epithets of prajñāpāramitā also. In the Chinese Heart Sutra, it is 大明咒  dà míng zhòu, where 大 means 'great' and 明咒 = vidyā. Due to the ambiguity of the characters and the confusion over the original meaning this is often translated as "great bright mantra". See e.g. Mu Soeng's recent translation and commentary on the Chinese version. Soeng, like Red Pine, simply ignores Nattier's findings. In the Chinese 咒 = vidyā also. Hence the change I have suggested in the Sanskrit: that "mantra" (qua word) is eliminated from the text and replaced everywhere with vidyā. For the argument in more detail see: Heart Sutra Mantra Epithets.
In Nattier's article she notes that the epithets passage has been traced by Nobuyoshi Yamabe in various Chinese translations of Pañcaviṃśati and Aṣṭa. I have been working on a comprehensive list of the counterpart passages in the basic Prajñāpāramitā texts in Sanskrit and Chinese. There are in fact only two passages, but they recur across two languages and multiple translations of multiple texts and so number about two dozen in total. I hope to publish this information before too long. Using electronic searches, I also came across a counterpart in the Rgs. In Chinese the passage is (T 8.229 678.a4-5): 大明般若諸佛母，
能除苦惱徧世界，
所有三世十方佛，
學此明得無上師。  This great techne of perfect wisdom is the mother of all Buddhas,
Able to remove distress in all world spheres,
All the Buddhas of the three times and the ten directions,
Schooled in this techne are the supreme masters. We can identify it as a counterpart because of its place in the sequence; its use of mahāvidyā in connection to prajñāpāramitā; and because it connects the vidyā with the buddhas of the three times and ten directions. The latter also links it to the second of two possible Pañcaviṃśati passages that are the basis of the Hṛdaya epithets (and the more likely of the two). In this translation mahāvidyā is rendered as 大明 dà míng (line 1), while vidyā in line 4 is simply 明 míng, in line with the practice of the day.

There are two main recensions of the Sanskrit Rgs and I have used recension A from the critical edition published by Akira Yuyama. Vaidya's edition is based on Recension B mss and has only minor differences in this verse which are discussed below. Conze describes the metre as "irregular Vasantatilaka" though my sources suggest that this is a 14 syllable metre, with a caesura after 8, i.e.:
– – ∪ | – ∪ | ∪ ∪ – ॥ ∪ ∪ – | ∪ – – (∪ light; - heavy; ॥ ceasura)
Rgs has 13, 14 and 15 syllable lines, with 15 seeming to be the norm and the verse we're looking at is quite regular. The final pattern of Rgs 3.5 does match the post-caesura portion of Vasanatilakā, i.e. | ∪ ∪ – | ∪ – – .
Note 21 Nov 2014. In a comment Kevin suggests reading the initial two light syllables ∪ ∪ a one heavy –. This would result a perfect match with the pattern found in references: (∪ ∪) – ∪ | – ∪ | ∪ ∪ – || ∪ ∪ – | ∪ – –  The text is not really in Sanskrit, but rather in a Prakrit that has been Sanskritised to some extent. It's quite near the Prakrit end of the Buddhist Hybrid Sanskrit spectrum, though this verse looks more or less like Sanskrit. Conze's translation is based on his "corrected" edition of Recension B, published in Russia by E. Obermiller and (not infrequently) on the Tibetan edition (Yuyama 1976: xlvii). I will compare both, but favour Recension A as found in Yuyama (1976). The text of the Rgs (A) verse which corresponds to the Chinese above is: mahavidya prajña ayu pāramitā jinānāṃ |
dukhadharmaśokaśamanī pṛthusattvadhātoḥ ||
ye ’tīta’nāgatadaśaddiśa lokanāthā |
ima vidya śikṣita anuttaravaidyarājāḥ || Rgs 3.5 || ∪∪ –  * | – ∪ | ∪ ∪ – || ∪ ∪ – | ∪ – –  (* see discussion)
∪∪ – ∪ | – ∪ | ∪ ∪ – || ∪ ∪ – | ∪ – –
    – – ∪ | – ∪ | ∪ ∪ – || ∪ ∪ – | ∪ – –∪∪ – ∪ | – ∪ | ∪ ∪ – || ∪ ∪ – | ∪ – – This perfection of wisdom of the Jinas is a major techne;
In the realm abounding in beings, whose nature is suffering, grief, and darkness.
The world protectors of past and future, in the ten directions, who;
Trained in this knowledge, are the unexcelled kings of the knowledgeable. The overall similarity of content shows that these two are the same passage, and the numbering also accords. That said some interesting differences occur as we would expect from the introductory comments based on Yuyama's observations about the state of the Chinese text.

The first line in particular marks this passage out as not being Classical Sanskrit. In Sanskrit it would probably read: mahāvidyā prajñā ayaṃ pāramitā jinānām | Such differences might appear trivial to the non-philologist, but all to often it is these differences in vowel length and final syllables that make the difference between languages. One can see that, here at least, the metre is fairly regular and in fact the Classical Sanskrit spelling would spoil the metre!
In line 1 measure 2 the ya in vidya does not make position. It is followed by pra which ought to make it heavy. The Pāli spelling would be paññā so it may be that the Prakrit speaking author pronounced prajña more like Pāli i.e. /pa/ rather than /pra/ and thus thought of ya as light. Or it may be an adjustment metri causa. Also the caesura occurs after the pā of pāramitā which is quite poor poetry. The Chinese (line 1) introduces the phrase 諸佛母 'mother of all the Buddhas' as an epithet of prajñāpāramitā. This may relate to the time period of the translation. A translation of Aṣṭa from 985 CE gives the title as《佛母出生三法藏般若波羅蜜多經》Fúmǔ-chūshēng-sānfǎcáng-bōrěbōluómìduō-jīng. 佛母出生三法藏 means something like: "The mother of the Buddhas that gives birth to the casket of the three Dharmas"; while 般若波羅蜜多 is the standard transliteration of prajñāpāramitā. And note that the title of Rgs also contains the phrase 佛母 'mother of the Buddhas'. This is an epithet of prajñāpāramitā even in early texts, but seems to have become more important by 10th century in China. 
Line 2 is interpreted in a more positive sense in the Chinese version. The Sanskrit merely notes the characteristics of saṃsāra (misery and grief) while the Chinese insists that the vidyā is able to relieve the suffering. This change is consistent with parallel changes in how the Buddha was seen in the Mahāyāna that I noted in my recent article in the Journal of Buddhist Ethics (21): Escaping the Inescapable: Changes in Buddhist Karma. What we see is the Buddha becoming more like a messiah in his ability to intervene in human affairs to benefit people. In particular in the revised (Mahāyāna) versions of the Śrāmaṇyaphala Sūtra, King Ajātaśatru, who has killed his father, is excused from a lengthy stay in Hell simply by meeting the Buddha. It seems that the idea that a Buddha, or in this case prajñāpāramitā, was unable to intervene was unacceptable to Mahāyānavādins. As was the idea that a Buddha might not return to this world as a saviour despite having won liberation from it.
Line 3 shows minimal variation between the two versions, except that the epithet lokanāthā 'protectors of the world' is exchanged for 佛 = buddhas. Since Faxian was translating in verse he may well have made a change like this for the sake of preserving the metre (metri causa). Chinese verse is restricted not only in the number of characters, but sometimes in the pattern of tones also, though we don't have reliable information about tones from Middle Chinese as far as I know.

Line 4 in Prakrit uses a simple play on words that might have been confusing in Chinese. One who trains in the vidyā becomes a supremely knowledgeable (vaidya) king. Here vaidya derives either from vidyā and means 'of or related to vidyā'; or from veda with much the same meaning. In any case someone who "knows" is "knowledgeable". (Note that "Vaidya" is the surname of one of the editors of the Sanskrit text.) In Chinese however two cognate words like vidyā and vaidya would be represented by the same character: 明 míng. Since this might be confusing, Faxian opts for 師 shī, which less ambiguously (and more concisely) conveys the sense of "mastery" and "expertise". Faxian does however retain 無上 wú shàng as a rendering of an-uttara, both meaning 'none higher' or 'unexcelled'. 

Conclusion
If Conze is correct then this mention of prajñāpāramitā qua vidyā in Rgs may be the original passage. However the chronology is complex. Between the composition of Rgs, the copying of the ms. that recension A is based on, and the Chinese translation ten centuries have passed. These texts are known to change over time. For example the Sanskrit parallel in extant Aṣṭa is much more elaborate than the version in extant Pañcaviṃśati suggesting that the manuscript of Aṣṭa is later, though overall we observe the opposite. In general Pañcaviṃśati is a development of Aṣṭa but apparently different parts of the texts evolved at different rates.

So any differences may be due to differences in the text rather than changes introduced by the translator. For all we know Faxian might be absolutely true to the text he had before him. However there are indications of adaptation to both cultural assumptions and to metric necessity.
Most commentaries on the Heart Sutra project late, synthetic views back onto the text. Thus for the recently published Zen commentaries  (e.g. Red Pine or Mu Soeng) the text is almost a tabula rasa onto which the ideas of Zen are inscribed, drawing on the Sūtra's status for authentication. Conze's commentary, influenced no doubt by D T Suzuki, takes a similar approach. Commentators like Pine and Soeng set out to tell a story about Zen based on the Heart Sutra. They seem unaware of any tension between the story they wish to tell and the text itself; and blithely gloss over any inconsistencies. Neither have any time for Jan Nattier's discovery. Pine talks himself out of having to take it seriously on spurious grounds, while Soeng notes the article and then proceeds as if it were never written. The religious story they wish to tell overrides any inconvenient historical or philological facts. And yet both writers are praised for being "scholarly".

For some scholars this genealogical approach to re-used passages is texts is intrinsically interesting. The re-use of passages and texts is a distinct subject for study in Indology (see Elisa Freschi on academia.org, her blog, and Indian Philosophy Blog). In the case of the Hṛdaya however it also opens up an entirely new way of reading the text (an hermeneutic). We can see that the Heart Sutra is thoroughly rooted in the early Prajñāpāramitā texts and that at the very least we need to allow that the author of the text (working between about 400 CE and 650 CE) had that kind reading in mind. It is possible that we see in the Heart Sutra an epitome of early Mahāyāna/Prajñāpāramitā thought rather than a legitimation of later readings which synthesise many elements of Mahāyāna thought and manifest as new forms of Buddhism like Zen or Gelugpa.
In which case we ought to be looking at the characteristic ideas of the early Prajñāpāramitā texts for the foundation concepts that allow us to understand the Heart Sutra. This exploration is a large part of what I will be doing over the next few years. Clearly there are many continuities with a particular stream of early Buddhist ideas and practice. For example, meditation practices such as the skandha reflections provide continuity. And an obvious discontinuity was the rejection of Abhidharma Realism, particularly the Sarvāstivāda ideas that were expressed in pursuit of a solution to the problem of Action at a Temporal Distance (I've yet to discover a specifically Prajñāpāramitā solution to this problem, though Nāgārjuna's solution may give us hints about what to look for). In any case there is a great deal of research on early Mahāyāna that modern commentators pay lip-service to, but fail to incorporate into their narratives. I'd like to revise the story of the Heart Sutra, particularly in the light of Nattier (1992).
~~oOo~~
Bibliography
Chinese text from the CBETA version of the Taishō Edition of the Chinese Tripiṭaka.  Falk, Harry and Karashima, Seishi. (2012) A first‐century Prajñāpāramitā manu-script from Gandhāra - parivarta 1 (Texts from the Split Collection 1). ARIRIAB XV, 19-61. Online: https://www.academia.edu/3561115/prajnaparamita-5 KIMURA Takayasu (2010). Pañcaviṃśatisāhasrikā Prajñāpāramitā. Vol. I-1, Tokyo: Sankibo Busshorin 2007. Online: http://fiindolo.sub.uni-goettingen.de/gretil/1_sanskr/4_rellit/buddh/psp_1u.htm [Input by Klaus Wille, Göttingen, April 2010].   Nattier, Jan. (1992). The Heart Sūtra : a Chinese apocryphal text? Journal of the International Association of Buddhist Studies. Vol. 15 (2), p.153-223.  Studholme, Alexander (2002). The Origins of oṃ maṇipadme hūṃ: A Study of the Kāraṇḍavyūha Sūtra. State University of New York Press.  Vaidya, P. L. (1960) Aṣṭasāhasrikā Prajñāpāramitā. The Mithila Institute of Post-Graduate Studies and Research in Sanskrit Learning. Also online: http://www.dsbcproject.org/node/8242  Yuyama, Akira. (1976) Prajñā-pāramitā-ratna-guṇa-saṃcaya-gāthā (Sanskrit Recension A). Cambridge University Press.