Atheist: A person who denies the existence of worshiped beings called gods. Atheism is NOT a worldview nor is it a philosophy. It exists ONLY as an opinion on religion. Ayn Rand (the supercapitalist) and Lenin (the supercommunist) have diametrically opposite worldviews yet both are (were) atheist. Although many atheists do deny the possible existence of any supreme power, not all do and in fact accept the remote possiblity of powerful intelligence(s) beyond our reasoning. Let's say Star Trek 1 really happens and we discover some giant, supremely powerful space probe. Are Kirk and Spock suddenly 'theists'? NO! This is just another event, phenomena, singularity that science will study. The probe isn't hearing prayers, asking us to build churches with our own money, demanding that we believe in it, asking us to kill infidels. It's a natural being - a natural powerful being - but not a god.
What about atheism as lack of belief in a god or gods? After thinking about this for quite awhile, I've come to the conclusion that defining atheism in this way is a good debating strategy but doesn't hold as a legitimate definition. According to proponents of this "strategy"; an atheist is supposed to define himself as "lacking belief" thereby making his position the default position if no conclusions can be reached. Well, not believing should always be the default position forcing the believer to prove his claim and the "lacking belief" definition shouldn't make a difference one way or another.
Now let's examine "Lacking Belief"; does it work? A-theist means AGAINST or ANTI theism; it does not mean indifference towards or ignorance of theism. To be an atheist you must have made a hard decision on the nonexistence of gods. An atheist is not just indifferent or ingorant, that is an agnostic. An atheist is someone who has made a conscious choice not to believe in god(s).
Are babies atheists? Are trees and dogs atheists? Are agnostics atheists?
Let's say that there are people who deny the existence of black holes. These people are called a-boles and have a whole litany of evidences against the existences of black holes. Can we say that a-boles are simply people who "lack belief" in black holes? Does this mean that every 6th grader and aborigine is by default an a-bole? In the same way atheists are people who DENY the existence(s) of god(s) and are very good at explaining why these creatures do not exist. Someone who simply "lacks belief" is a "True Agnostic" on my chart as he has not made up his mind as to the existence or nonexistence of any gods. Only when someone says "No way is there a god." can he be called an atheist.
Belief
1) The mental act, condition, or habit of placing trust or confidence in another: My belief in you is as strong as ever. (Well - this is irrelevant to atheism.)
2) Mental acceptance of and conviction in the truth, actuality, or validity of something: His explanation of what happened defies belief. (Belief is a positive act. You believe in the TRUTH or VALIDITY of something.)
3) Something believed or accepted as true, especially a particular tenet or a body of tenets accepted by a group of persons. (What tenet or body of tenets do atheists accept?)
Atheism or Not-Believing-in-Leprechauns or Not-believing-in-Grey-Aliens is NOT a belief - it is a POSITION on a belief. If atheism was a belief then it could exist on its own without the existence of belief in religion. Since atheism requires religious belief to exist it is therefore a position on a belief rather than a belief. None of us believe that VooDoo dolls work; there is no word for this position because the belief in VooDoo dolls is so tiny as to be insignificant. If we were to name a disbelief in every superstition that humanity has grown out of then we would be bogged down with thousands of words that indicate lack of belief. Instead - when beliefs die away, the counter-argument simply dies with them.
Faith: Faith is the belief in insubstantiated ideas or dogma irregardless of lack of evidence or even with evidence to the contrary. Confidence is a rational assumption in the behavior of known forces. You have confidence that your keys will start your car. You have faith that your car will fly into the sky sometime.
God: A powerful, worshiped being sporting a theology.
What about: Supreme Intelligence and creator of all? Using this definition most of earth's gods are not actually gods. Zeus was not a Supreme Intelligence and creator of all yet it is a worshiped being with a theology.
What would we call an all-powerful, supreme entity? If it is unworshiped, it is not a god until a religion is created around it. An all-powerful being may not be anthropomorphic and we may not even understand it as any different from a natural event. Is the Big-Bang a god? If we stick a brain into Big-Bang, it creates everything and goes its way - do we call that a god? No - it has godlike powers but it is a natural event - the most natural event in the universe. Science may discover and try to understand it but no goats are sacrificed in its name and it hears no prayers - it is not a god anymore than a blackhole is a god because of its power.
Also, when someone uses 'God' as a formal name we must assume that he means Jehovah, the heathen-killing, tribal wargod of the ancient Hebrews. Most every other religion gives its god a name.
Theist: Generic term for an adherent of a god-based religion. A Muslim is always a theist. A theist is NOT always a Muslim.
What about: Theist (n). Believer in a non-descript god of no properties and no theology?
1) A god without a theology is not a god - it is an alien or supreme intelligence. 2) This type of theist is effectively no different than any atheist and certainly will not be fervently defending "Intelligent Design". 3) This type of theist, like unicorns, does not exist. The only time I see a fervent, argumentative 'theist' on a website or a messageboard - it is merely a Christian in disguise - too scared to reveal his fragile theology to those darned skeptics. 4) There is already a name for people who believe in a noncommunicative supreme intelligence - Deists.
Theologian: a blind man in a dark room, searching for a black cat that isn't there - and finding it!
"Humanity's deepest desire for knowledge is justification enough for our continued quest. And our goal is nothing less than a complete description of the world we live in." S. Hawking
"I prefer to be true to myself, even at the hazzard of incurring the ridicule of others, rather than to be false, and to incur my own abhorance." F. Douglass