I don’t want to always be a schoolmarm, correcting the misuse of this or that term, but there are a few that cry out for attention. “Gnostic” is one such word. It has recently come to be a shorthand to describe a variety of concepts, typically those which prioritize the spirit or the mind to the body. Anyone who believes in the priority of the intellect could be called a “Gnostic” under this usage, as well as anyone who thinks that the soul is on a different plane of being than the body. “Gnostic” is also employed to critique those who hold to idealism over materialism. Strangely, not a few of the modern “anti-Gnostics” have gone so far as to deny the soul’s ability to exist apart from the body, thus creating a heresy of their own in the opposite direction.
But according to folks like Kurt Rudolph, we don’t actually know much about the original Gnostics. We know that they transcended the bounds of any one religion, instead appearing in Judaism, early Christianity, and many of the Eastern Religions. What’s more, they were critiqued by both pagan and Christian alike. Contrary to the modern use of the term “Gnostic” to apply to any and all “Platonic” thinkers, Plotinus wrote an entire book against the Gnostics.
There are a few core principles of Gnosticism. “Gnosis” is obviously at the heart of it all, and it means a special hidden knowledge that only the elite are privy to. This knowledge would save one from the world. And the second principle, which is perhaps more famous (or exploited, depending), is that the creation is evil. Gnosticism believes that evil is eternal and that therefore the original creating principle (if such even makes sense under their system) is evil, or that there are various original principles (and perhaps they are indeed the same). This latter belief is why the Gnostics wanted to escape the body and creation. It was because they wanted to escape evil.
This is significantly different than the more common belief in the primacy of the spiritual. That belief, held by Platonists, Jews, and Christians alike, always held that there was but one Eternal and that the Eternal was good. Evil was foreign to the Eternal and could not exist forever.
And since Goodness is supreme, there was no need for a hidden wisdom. Everything that is has something of the Good to teach us.
And I’d say that those are significant differences worthy of noting in our contemporary conversation.
You can draw parallels in thought, of course, but these have to be done with care. We should not be able to say that A is essentially the same as “not-A” simply because both share the quality of being “not-B.”