Surely the relative pronoun is not the antecedent or postcedent. The antecedent or postcedent is the noun or substantive which the relative pronoun refers to, is it not?Alan Patterson wrote: 1ὃ ἦν ἀπ' ἀρχῆς, ὃ ἀκηκόαμεν, ὃ ἑωράκαμεν τοῖς ὀφθαλμοῖς ἡμῶν, ὃ ἐθεασάμεθα καὶ αἱ χεῖρες ἡμῶν ἐψηλάφησαν περὶ τοῦ λόγου τῆς ζωῆς
ὃ functions as a conceptual (it references the topic to be discussed, the big picture) antecedent or "postcedent," as here. Indeed, it could be cogently argued that it refers to περὶ τοῦ λόγου τῆς ζωῆς.
Actually, in the grammars (Smyth, Robertson) they say 'antecedent' whether it comes before or after. Is that because it is logically prior, or somesuch?
Smyth 2509 says the demostrative pronoun is often omitted when the relative clause precedes the main clause. If τοῦτο is accepted as the grammatical antecedent, then I think it would be confusing to introduce a new idea of a 'conceptual antecedent', which might be something else. Clearly, when one reaches περὶ τοῦ λόγου τῆς ζωῆς, one finds out more about what this τοῦτο is about - it's like a descriptor of the antecedent. We're building up a picture: this was a) from the beginning b) something we heard e) something we touched..
But then again, one could see each of the relative pronouns with their implied demonstrative as having a different referent: ὃ ἀκηκόαμεν for example is the sum total to the audial messages received, to put it very prosaically - and then περὶ τοῦ λόγου τῆς ζωῆς could be telling us what the messages were about. Of course, they all naturally amalgamate themselves into something which seems to me to be primarily their witness of the word of life. This we announce to you..