The 8th has already been. Called the 8th at the time, referred to as the eighth Ecumenical Council in the Encyclical of the Eastern Patriarchs 1848 signed by the patriarchates of Constantinople, Alexandria, Antioch and Jerusalem.
"xi. It [filioque] was subjected to anathema, as a novelty and augmentation of the Creed, by the eighth Ecumenical Council, congregated at Constantinople for the pacification of the Eastern and Western Churches."
"..the Papacy. Some of the Bishops of that City, styled Popes, for example Leo III and John VIII, did indeed, as has been said, denounce the innovation, and published the denunciation to the world, the former by those silver plates, the latter by his letter to the holy Photius at the eighth Ecumenical Council, ..."
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About a century (?) after the Photios/John VIII (?) the RC reverted back to the previous "eighth" which ousted Photios and claimed papal supremacy, so the RC would rather forget the eighth altogether I think, as it brings it back into discussion - this was certainly the idea behind lifting the anathema's because then the joint statement said something about 'putting the mistakes of the misguided fathers behind us' or some such words. (Sorry for the question marks and such, will look these up over the weekend - unless anyone can post them earlier)
And, I think the Russians limited it to 7 under the Jesuit influence which Peter the not so Great brought in to Russia because he admired their education.
What's interesting is why these same patriarchs who took as read that the 8th was a done thing should now be talking about holding an eighth.
Myrrh
