I am struggling through Plato's apology using Helm's Reader edition. I am, for the most part, keeping up and I don't mind not quite getting everything as yet, but there is one part (the bold in the quote) which is really bugging me:
The best I can come up with is:εἰ μὲν γὰρ τοῦτο λέγουσιν, ὁμολογοίην ἂν ἔγωγε οὐ κατὰ τούτους εἶναι ῥήτωρ.
For if they are saying this [that a clever speaker is one who speaks the truth], I would have to agree with them, [but if] not, I am a speaker not according to them.
Essentially, I think that Mr Socrates is saying that he is a speaker but not in the way that they actually mean it as he feels a good speaker is one who tells the truth, but they are speaking lies, and thus implying that what they define as a good speaker is actually someone who tells falsehoods.
The thing that confuses me is the negation 'οὐ'. Without it, I would understand it as saying '... I would have to agree agree that I am, according to them, a speaker [if they mean someone who speaks the truth].
Any help with this would be much appreciated, as I've been perplexed by this for a little while now.