Probably atheism has existed since the origin of theistic, since it is difficult for all members of a society share their religious thought. Throughout history, the opinions tied to religion theists have generally had a dominant position in society. Opponents of these positions have not always had the opportunity to express their views in public due to phenomena of "witch hunt" or the terrible Inquisition in Christian Europe. So at different times in history, it is rare to find atheistic views in manuscripts or other historical references.
Atheism is, in a broad sense, the non-belief in gods or other supernatural beings. In a narrower sense, atheism is the position that holds that there is no deity. Some define it as a doctrine or position that rejects theism, which in its most general form is the belief in the existence of at least one deity. In a broad sense could be included within the definition of atheism, both atheists, who do not make explicit the existence of gods, as those that do not believe in their existence, have no evidence or conviction for his rebuttal. By strictly excluding the latter, called agnostics, atheists of defining. Agnostics and atheists reject recognized as atheists because they believe all inaccessible to human understanding of the divine knowledge and what transcends experience or simply irrelevant.
The term atheism includes those who show a lack of belief in any god or deity. According to historian Francisco Diez de Velasco, an atheist or deny the existence of a god or gods do not necessarily belong to any religion, there are religions like Buddhism who deny the existence of God or do not mention the existence of God one and therefore are more correctly atheistic non-theists. The tenets of atheism are contrary to the holding of religious beliefs and involve a critique of religion.
Question 1
H.J. McCloskey, in his article, “On Being an Atheist,” presents a series of arguments in an effort to justify his atheism. His strategy includes dissecting specific claims made by those who advocate the existence of a Creator, in general, and the Christian God, in particular. He begins his series of objections by way of summarizing each of the arguments, which he calls “proofs,” concluding that neither of them, individually, should create enough comfort or security to believe in God. However, if we take the cumulative case approach in explaining the existence of God, what we have is successions of truths that, individually, cannot bring about definite proof, but, together, create concurrence. Additionally, if the objections are examined separately, McCloskey faces the same flaw he protests: that each of his objections is fatal to the existence of God
Question 2
Adhering philosophically to idealism or to materialism, atheists often have therefore an imminent ethics (as opposed to such transcendent Christian ethics based on the system philosophically realist), i.e. they are not burdened with absolute moral rules instead assuming the moral relativist positions. The fundamental difference between theistic and atheistic morality, is that the former comes from divine authority, while the second of humanism, as a result of personal reflection and respect for social norms.
McCloskey's first objection is to the cosmological argument—the argument from existence. He claims that the “mere existence ...