The key here is denial/ignoring rather than "positive" or "negative" [or evil, darkness, or toxic]

From the article:

"So what is positive and what is negative –to deny or ignore the darkness within and around one, or face it, and tell things as they are?"

And what is this "darkness"?:

"Just what does this rather abstract term ‘darkness’ refer to? Darkness, as I see it, is the toxic byproduct of innumerable generations of non-self-knowing people, generating a growing subconscious substratum of fear, hate, and self-centered activity in collective consciousness. "

Fine, whatever. But that's one way to describe what evil is.
I don't know if it's a particularly helpful way to describe evil but that is to some degree "practically" straight out of the bible. Not that the bible has some kind of monopoly on the concept.

So in other words if you do not recognize the "toxic byproduct of innumerable generations of non-self-knowing people" or you think "human nature as essentially good"
and thereby ignore the "toxic byproduct of innumerable generations of non-self-knowing people".
Then, you are, generally speaking, f*cked.