[philk]

Sure, but if you respond there are two categories of people:

a) People who generally like you and your essays, who will continue to agree with you, and

b) People who don't like you or your essays, who will take it as further evidence that you don't know what you're talking about.

and by replying you're just making the people from category b) post more.

But here I do know, and everyone knows I know

Not really. There's no "this post was read by pg" flag next to it. If you don't reply, at worst people will think you just couldn't be bothered to respond, which isn't a bad thing.