Criticism of Criticism

"What are you writing?"
" A criticism."
"Of?"
"XXX by ZZZ."
"But that's a criticism in itself. I mean the title you are mentioning is a crticism of the first phase of writings by YYY."
"I know, but since ZZZ published her criticism, I am entitled to write a piece criticising it. Do not forget we are critics."
" So, who criticises yours? Have you planted anybody yet?"