There seems to be a neverending confusion and conflation of the terms “atheist” and “agnostic”. In this post, I hope to clear up the difference between the two.

From my experience, the two most frequent and important points to address in this matter are:

1) The false claim that, by definition, atheism is the positive assertion that no godds exist; and

2) The profession by many who, according to the precise meanings of the two words, are in fact both atheists and agnostics, that they are agnostics, but not atheists.

Before addressing what’s problematic about these two points, let’s examine the etymology of the words “atheist” and “agnostic” in order to more clearly undeerstand their definitions.

Both words begin with the prefix “a-“. The definition found (as all subsequent definitions are) in wordinfo:

a-, an-
(Greek: prefix; no, absence of, without, lack of, not)

Just as in the words “apolitical” or “areligious”, which respectively mean “not political” and “lacking religion”, this suffix simply means “to lack”. A-theism, then, is a lack of theism, and a-gnosticism a lack of gnosticism:

gno-, gnos-, gnoto-, -gnostic, -gnosia, -gnomic, -gnomonic, -gnomical, -gnomy, -gnosia, -gnostic, -gnosis +
(Greek: know, learn, discern)

theo-, the-, -theism, -theist, -theistic
(Greek: God, god, deity, divine)

As in the words “diagnose” (literally, to know thoroughly) and ignorance (literally the opposite of knowing or not knowing), the root “-gnostic” pertains to knowledge.

The root “-theist”, on the other hand, pertains to belief in one God, or gods. Just as polytheism is the belief in multiple gods, and pantheism is the belief that (roughly speaking) everything is god, atheism is a lack of any belief in any gods.

The fundamental distinction to make here is the difference between belief and knowledge. It is entirely possible to have one without the other. Many people, for example, believe in ghosts although they do not claim to have any knowledge – whether by personal experience or external evidence – of the veracity of their existence.

So, when it comes to atheism and agnosticism, these are not different positions on the same linear spectrum. They are answers to two entirely different questions.

In the case of theism or atheism, the question is, “Do you believe that one or more gods exist?” If your answer is anything less than an affirmative “Yes”, then you are an atheist. You lack theistic belief.

And in the case of gnosticism (in the simple sense of peertaining to knowledge) or agnosticism as applied to deities, the question is, “Do you claim to have knowledge of the existence (or nonexistence) of one or more gods?” And if you cannot answer “Yes” to this question, then you are an agnostic.

All four combinations of atheist/theist and agnostic/gnostic are therefore possible. It’s likely that most theists are gnostic theists, who not only believe in God, but also would claim to have knowledge of that God. There are, however, also agnostic theists, who maintain a belief in the existence of God without claiming to have any direct or indirect knowledge upon which to base that belief.

Likewise, the majority of atheists are most likely also agnostic; while remaining unconvinced that any gods exist, they do not go so far as to say they are absolutely certain than none do, or at least could exist (I would include myself in this category). Some atheists do take that extra step beyond lacking belief, however, and make the positive claim of knowledge that no gods exist.

And with that, being that it’s about 2:30 a.m., I’ve just got to cut this off short and hit the sack. I will follow this post up, hopefully this weekend, with a further explanation of why I find the two points at the top of this post problematic.