Ah, I see. In which case, then yes. I attack his credibility. I attack yours. I attack mine. You are biased. I am biased. He is biased. Everything you write is

Ah, I see. In which case, then yes. I attack his credibility. I attack yours. I attack mine. You are biased. I am biased. He is biased. Everything you write is tempered. Everything I write is tempered. His credibiltiy is compromised and the source must be considered, as is yours, as is mine. This shouldn't be controversial, yet here we are. Seriously, here we are.