There is also a problem of dealing with problems such as why is it wrong to rape or torture someone?
First of all there is no such thing as absolute morality or truth.
Have you ever heard of empathy? The way I and I'm sure most atheists decide whether their actions are right or wrong is by looking at a action from the other persons point of view.
For instance I would not want to be tortured so if I myself don't want to be tortured why would I want someone else to be. I don't need god to tell me what is wrong or right.
Are the truths of issues decided by the majority? Most atheists would say yes.
Well, I personally have never said this I don't know anyone that has. I agree that in a society something may be acceptable that another society would frown upon, but just because something is accepted by a majority of people doesn't mean it is correct. The reason most people are Atheists is simple because there is no evidence supporting ANY god.
What I think you do not understand is that Atheism is the position that there is no god. Nothing more there is no 10 commandments for Atheism there is no Atheism bible. So to define it as a "philosophical system" is somewhat misleading.
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