I don't believe in a god, and I never have, for a few reasons.
Firstly, I don't believe in free will. I believe that life works in a crazy "butterfly effect" way; that in any given circumstance, there is only one option that an individual would ever choose (due to the fact that we are neurologically wired to behave a certain way in certain situations, and hence we are not random), and everybody's choices sort of overlap, and dictate our lives. So I believe that if the was a God, there is no "good life, bad life" side to things, no divine justice. He made us exactly how he meant to, and if anyone goes to "Hell" for all eternity it's due to His divine sadism.
Secondly, If god is the creator of all things, and has unlimited power (since he is the creator), why invent pain? Of course, to warn us of danger. Why invent danger? To add excitement to our lives, to contrast the good. But if he essentially created the universe, and hence controls the laws of logic, then why not contrast good with good? To say that pain is a neccesary part of life is stupid, because if there was a god there wouldn't need to be pain.
And Thirdly, if everything is there for a reason, what about tooth decay, metastatic melanoma, mad cow disease, fourth-degree burns, and of course, depression, an ailment which strips the world of any beauty.
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The scientist only imposes two things, namely truth and sincerity, imposes them upon himself and upon other scientists - Erwin Schrodinger
Member of the WP Strident Atheists