:dts:A human being is composite; we have for example left and right brains, etc. These halves communicate in order for “one” person to exist. Note, by extension: the incarnation IS STILL one “hypostasis” – eg: the “son”; therefore there must be communication for Jesus to be a single “God man” PERSON.
One can readily see the Latin conception of the internal processions, expressed in modern terms, in Fr. Hardon Modern Catholic Dictionary.
PROCESSION. The origin of one from another. A procession is said to be external when the terminus of the procession goes outside the principle or source from which it proceeds.

uch:
A principle, in the English sense of the word is a statement which works by “Excluding” other possibilities. For example: The principle, in physics, of least action – suggests an understanding based on excluding actions which are “maximum”. In visual processing fields, the “Hemholtz Principle” is stated succintly – “One can’t SEE significant information in pure noise”. (Therefore: If you see significant information – it ISN’T Noise).
Hardon — ugh – If the terminus of the principle, then, goes “outside” the principle – the dictionary has become somewhat nonsensical. The use of “origin” is fine…

(She!!!) sheesh…
Procession carries with it the idea of “motion” or “act”. Hardon mentions “sign” – of a divine person from another. It is here, I think, that the Latin understanding given by Hardon is at it’s weakest. For I recognize as signs the value of a “Father” (we have human ones as examples), and Sons… And therefore there is a universal sign of Fathers being origins of “Sons” as a procession. But one can’t appeal to that kind of sign value very successfully in terms of “spirit” and “person”. I don’t outright disagree with Hardon, here, but am simply pointing out that his definition would suggest a “sign” value of 4 “persons” according to experiential discovery. ( Or else the idea of “origin” has now become equivocal. )
For in natural human beings “breath” is something that originates in each who breathe.
It is precisely here that writers such as Bp. Kallistos Ware have objections worth considering.
This is nonsensical. Such an item could in no way come in contact with anything else by definition, and therefore has no existence knowable to anything else outside. This is Thomism to a fault or an UNQUALIFIED definition. Fr. Luan Tran once tried to claim to me that he “subsists” in himself – and I had to tell him, “No. You can’t.”
You are in the body of Christ as a priest. Even in the Vatican documents, the use of “subsist” (exist?!) means to exist contingently. Careful study leads me to conclude that no DOGMATIC definition or usage has succeeded in raising Thomas’ conception to a definiton worthy of the Catholic population in general.
In the Greek, hypostasis often is used in scripture to represent a man, and I will recheck – but it also signifies all his immediate family – children and wife; possibly even slaves. I doubt Hardon is being respectful of Greek sentiments in his definition.
A beautiful example of “principle” in the English sense, by contextual clues proving my earlier assertion…
The CCC …
I think what is really being overlooked by Hardon is the simple fact that the sign value of “Spirit” (breath, ruah) is life. Just as scripture says the “Life” is in the “Blood” – I (at least) am in a position to understand even today, as with the ancients, that breath itself is “IN the blood”. To be alive requires breath – and breath has a motion – it is a ceaseless procession. It is here that the single breath between Father and Son is an analogy I would present for cross examination under both East and West and see where it leads us.