Atheism's Definition - Stanford Encyclopedia of Philosophy

[Darkstar]

Your quote said nothing about "gnosticism." In fact if you look at the origin of the word agnosticism, you'll see it has nothing to do with gnosticism. The current use of the word too, has nothing to do with gnosticism.

It seems you are correct. I guess that's why it isn't a-gnosticism.

On positive and negative atheism, I'm a bit more accepting, since some significant minds, like Anthony Flew and Michael Martin are on board with it. But like the OP shows, Flew's claims were part of a strategic argument (he was trying to argue that atheism was the default position) which was ultimately rejected, and afaik his work needs significant massaging to make it say positive and negative atheism.

Michael Martin's work supports it more clearly, but these two are a clear minority, and I'm very tentative to accept it.

I think that simply taking the suffix a- (without) and applying it to theism would result in a-theism (without theism), which would not necessarily imply direct belief that god does not exist.

What is my conclusion at the end of this? I think at minimum, you need to accept that the alternative definition is a valid alternative, even if it is not the one you prefer.

I am not completely certain what you mean by this. I have never suggested that those who actively believe god does not exist aren't atheists. It would be so easy if agnostic atheists could be people who simply don't believe whereas normal atheists could believe the opposite, but that excludes the possibility of belief without claiming knowledge. Those who actively believe against are generally now called 'hard' or 'strong' atheists.

In short, both those who simply don't believe and those who believe the opposite are both considered atheists. If by accepting the alternative definition, you mean something akin to the Merriam Webster definition:

Definition of ATHEISM

1 archaic : ungodliness, wickedness
2 a : a disbelief in the existence of deity
b : the doctrine that there is no deity

Where

dis·be·lief noun \ˌdis-bə-ˈlēf\
: a feeling that you do not or cannot believe or accept that something is true or real

(2a representing negative athesim, and 2b representing positive), then sure, I can.

Lastly, just as many agnostic atheists simply go by 'atheist', an agnostic who is only atheist on account of not being theist (but really has no clue one way or the other) can simply go by 'agnostic' without making any misleading suggestions about their beliefs or lack thereof (heck, even someone who is pretty sure there isn't a god could technically still go by only 'agnostic' if they wanted too).