Quote from Cutten:
Like many English words, "atheist" is partially derived from Latin. "A" in Latin is used to mean "without". "Theism" is "religious belief". So "a-theism" means "without religious belief".
Some examples - "a-moral" means without morality, it does not mean evil (that would be "im-moral"). "A-typical" means lacking in typical qualities - it does not mean the opposite of typical qualities. "A-sexual" means lacking in sexual behaviour or interest, it does not mean being anti-sexuality.
Thus atheism does not mean that you are sure god does not exist. In fact, since it is impossible for us to prove that a logically possibile entity does not exist, no rational person would say "God definitely does not exist".
There are two main forms of atheism, which we could call strong and weak. Both forms think that there is insufficient evidence for the existence of god. Weak atheism is the view that religious people are rational, but simply misjudge the credibility of the evidence - thus theists are rational but mistaken in their assessment of evidence.
Strong atheists, such as myself, think that no objective and rational person could possibly form religious belief if they treated the evidence for god's existence in the same way that they would treat evidence for the existence of a non-religious being (for example the Loch Ness Monster, Little Green Men etc). I believe that most religious people are "stupid-irrational" i.e. simply lack logical reasoning skills, are gullible, or have insufficient knowledge or critical faculty to interpret evidence for reglion, or simply have not thought critically about their religious belief. "Stupid-irrational" people are either the type to believe in astrology, lucky charms, con tricks and other frauds, or the type who accept ingrained social norms without really questioning their truth.
Strong atheists identify a second category of believer, "smart-irrational". These people have strong reasoning skills, are generally not gullible, often question entrenched beliefs, are very knowledgeable, and so on. In most respects apart from religion, they are quite similar to atheists. The strong atheist believes that such people have religious belief due to emotional and/or psychological need for "meaning" i.e. a need for explanation of important life questions such as morality, the origins of the universe etc. Whilst the atheist is also interested in such questions, he thinks that the smart-irrational believer has simply made one jump too far, unsupported by evidence. The smart-irrational person then, having made this jump, uses all his powers of debating, critical reasoning, knowledge and so on to try to rationalise this leap of faith.
Remember, there are virtually no religious people who say "well, I can't be sure, but on balance I think God probably exists". They all claim *absolute certainty* that god exists. The atheist does not think it is irrational to say "you know, the universe is such that I think it's quite possible it was created by an intelligent being". What is irrational is to claim certainty in the face of such paucity of supporting evidence.
It is a very common pattern in human belief systems for very intelligent people to belief things that are totally wrong. Then, when confronted by this fact, rather than change this belief they use all their powers to try to rationalise it - contrary evidence is challenged using every method possible, supporting evidence is rendered more persuasive, cunning debating tricks are used to mask evidence and paper over holes in logical reasoning, and so on. In almost all cases the smart-irrational person does not even think they are doing this, so strong is the emotional capital invested in their dogged belief.
One way you can detect rationalisation (defined as "trying to come up with reasons to defend a particular belief, rather than impartially assessing evidence in order to establish the truth") is by seeing a person's reaction when some of their arguments are discredited. If someone makes a point in favour of a position, and it is then established that this point does not apply, then a rational and open-minded person would then start to question their original position. A rationaliser, however, will simply find another rationalisation of their position, and will not question their original position or alter it at all.
They are a bit like a bad trader with superb analytical skills. The intelligent analysts are always the ones who lose the most, as they can always come up with reasons why they are right and the market is wrong. Equally, the intelligent believers are the ones who are most likely to cling onto religious belief, as they can deflect most common objections, and on the rare occasion that someone relentlessly calls them on the irrationality, they can usually fudge the argument sufficiently to allow them to continue holding the belief, often using a few mild ad hominem reasons (which they sincerely believe) as the final crutch of support.
What is strange is that they would find it laughable if someone else employed identical tactics to defend a belief widely mocked, such as belief in a flat-earth, little green men, astrology and so on. The fact that they mock such beliefs whilst not subjecting their own religious belief to the same stringency is rather puzzling.
I have attempted to find out from ARogueTrader and others why they appear to have this dual standard, but I have not seen an honest reply to this question. If anyone is aware of a theist explaining why they have certainty in their religious belief whilst not accepting other people's certainty of belief in Little Green Men, Satanism, Loch Ness Monster etc, then I would be interested hear it.