Like I said, you're not a trial lawyer. Lying or insanity has nothing, usually, to do with what people see and hear and then recall even minutes later, let alone months or years later. Sometimes the differences can be dramatically different, not just in trivial matters but also in material ones.
I think we must not be hearing each other on this one. :) Everything you say above is very basic and of course correct. Perhaps I should not have commented on a result based on an impossible premise. I am fine with leaving it that I agree with you that very often eyewitness testimony makes lousy evidence.
BTW, in the confusing English translation, it's "proceeds" not proceeded and the word has nothing to do with "sending" but, as Kosta points out, with origin. This makes a difference because we are trying, in the Creed, to describe the Triune God we worship. It is not bad theology to say that the Spirit is sent by the Father or by the Father through the Son but that is not what the Creed is talking about.
Assuming you would say that "origin" does not negate the concept of "eternalness", of what import is origin in describing a co-eternal and co-equal God? If it is purely extra-scriptural then we may well ascribe different meanings to the Creed we jointly recite. That wouldn't be the end of the world for me since Creeds are only human summaries of what I consider authoritative, they don't have authority on their own.
Origin does not negate "co-eternalness". The Hypostasis of the Trinity "is" before time came into being. Origin from the Father, however, is important lest Christians fall into any of a number of heresies; Arianism, Nestorianism, Macedonianism, Modalism (especially)...there are others.
"If it is purely extra-scriptural then we may well ascribe different meanings to the Creed we jointly recite."
You are of course free to believe what you will. The days of the Inquisition are over. The Church, however, has never had multiple "meanings" for The Creed, aside from the West unilaterally changing The Creed by inserting the filioque, which did change the meaning and was correctly anathemized by the East.
"Creeds are only human summaries of what I consider authoritative, they don't have authority on their own."
Because the Nicene Creed was adopted as a dogmatic statement of our Trinitarian Faith, it does indeed have authority on its own, at least within The Church.
The origin is understood to be eternal, i.e. the Son is eternally begotten by the Father, and the Spirit eternally proceeds form the Father. It's like saying the water wells unceasingly from the eternal origin.
But the existence of both the Son and the Spirit (and therefore the Godhead, the Trinity) is eternally caused by the Father who is himself un-caused; hence the monarchy of the Father.