How is the Acintya of Acintya-bheda-abheda defined? - Looking at original sources

Yes, perhaps with the exception of Dvaita.

Naturally, but this is NOT how the word is normally used by Gaudiyas. The word "acintya/inconceivable" used in acintyabhedabedha is what I am talking about. The different philosophical schools labeled Dvaita, Bheda, Abheda, Bhedabheda, Visistadvaita, etc. all speak about about their conceptions of the difference and sameness between Isvara, Jagat and Jiva, the three Vedantic tattvas. For example Ramanuja does NOT say that the realionship between the Jiva and Isvara is inconceivable. In fact he conceives of it like the relationship between the body and soul ie sarrira-sarriri bhava. One may say that this is NOT FULLY conceivable because the full nature of Brahman is inconceivable. However that is besides the point. It is a understandable conception. It is not a cop out. To simply label something as inconceivable is of course in itself a definition or conception. Nothing is gained by the word just as nothing is gained by the Advaitins with their anirvacaniya (cannot be described by words). It something truely cannot be described by words then even that description is incorrect. Just like the other Advaita fantasy that there can be something which is neither real nor unreal. Ludicrous. Similarly we gain nothing from defining the relationship between the three tattvas as acintya or inconceivable.

Even more than this the thing that irks me the most is that I have heard many Gaudiyas use this word "acintya-bhedabheda/inconceivably one and different whenever they feel the need. When any old problem presents two solutions a devotee is likely to just shrug and say "Well, I guess it's acintyabhadabheda!." This catch phrase even if it can be accepted as a Vedantic philosophy cannot and should not be used to answer all and sundry philosophical discussions.

Dvaita has never claimed that Brahman can be completely grasped by the intellect. However I suppose you were not talking about that.

Although the manner in which I usually write may make people think otherwise, my approach to an analysis, is to put myself in the position of the propounders and try to figure out what they were thinking and why, rather than try to force the conceptions that I am comfortable with, right from the beginning. (DH, kindly spare me your reply)

A-B-A has just put one more subject matter under the heading of the "inconceivable". Not without reason - "shrutes tu shabda muulatvaat". Baadaraayana himself has not failed to take exclusive recourse to scriptures when the philosophy seemed to give under the weight of his own line of reasoning.

Frankly, I doubt that the casual approach to the word "achintya" that is so very prevalent, usually in ISKCON circles, would make Jiiva Gosvaami happy.

According to Dvaita, this is just a rephrasing of their philosophy (minor points here and there debatable)

But what can be done if the matter is really like that. Afterall, it cannot be expected that reality present itself in a manner which makes our intellectual faculty comfortable. Attempts can be made, and a lot of them have been made. What Jiiva Gosvaami is trying to point out is that the total understanding of such a relationship is impossible. Philosophies can be built around analogies which are, more or less, close and perhaps has more to do with the comfort level of the faithful concerned. I would say, his concept of shakti and shaktimaan, for him, is also an analogy which he would not like to print on a T-shirt as "the equation of reality".

In fact it is the very nature of sad asad vilakshana tattva that is anirvacaniiya. There is no need to find tight logical fallacies where the speaker did not intend such a thing. May be, by the word "anirvacaniiya", some idea is being conveyed, not a challenge to prove it false there and then. While taking such a literalistic approach, one may misunderstand the underlying intent and shoot off in a tangent. Had it been so simple to throw away, we wouldn't have tons of philosophical literature being thrown between schools in each successive generation.

It attracts doubt because, in addition to its being somewhat absurd, there seems to be no mention of this peculiar category in the scriptures. In any case, categories like these find mention in naastika schools like Jainism.

The Gaudiyas, however, can just point to the entirety of the Shrutis in its direct simple interpretation to nail their point. Of course, this does get them into trouble, sometimes, when philosophers like DH pop up. Economy of words, it seems, is a luxury that philosophers can never really afford.

Seriously, can no-one point me to an early source in which this term was used? How recently was it coined? I recall hearing Jiva would have been the first to use it.

Unfortunately, this is not a direct reference to Jiva's writings. This is quoted from the 16th chapter of the parikrama-khaNDa of Bhaktivinoda's Navadvipa-dhama-mahatmya.

Now that you cited it, the idea of two principles from each sampradAya is rather peculiar, as we examine that in the light of the idea of our belonging to the Madhva-tradition. If I had to place those eight elements into a successive order of forming a unique characteristic in our tradition, in contrast to that which is rather general among all Vaishnavas, I would list them as follows:

1. The necessity of taking shelter of Radha. (Nimbarka)
2. The high esteem of the gopIs' love for Krishna. (Nimbarka)
3. The path of rAga-bhakti. (Vishnusvami)
4. Service to the devotees. (Ramanuja)
5. The concept of pure, unadulterated bhakti. (Ramanuja)
6. Exclusive dependence on Krishna. (Vishnusvami)
7. Service to the deity of Krishna. (Madhva)
8. Total rejection of mAyAvAda. (Madhva)

The sequence of the last five may vary, but I believe that comes close to how much each of the themes is featured in the writings of our tradition. The first three are certainly by far the most specific in terms of what defines us as Gaudiyas.

Interestingly, as we have observed before, we seem to have much more common with the Nimbarkis and the Vallabhis (the tradition of Vishnusvami) than we do with the Madhva-tradition.

Have you seen the mega entry in GVA? There is a lot of stuff about it. The term is acintya-bhedAbhedavAda. Jiva probably never used this expression. He refers to acintyatva in bhagavat-sandarbha 15 (Puridas edition). He refers to BhP 3.33.3.

Baladeva got more into it, but even he does not seem to have used the term. If you want to know who was the first to use the exact expression, it's probably going to be found in some writing after Baladeva. Are you still interested? I could do some more research.

-ek