Atheism, put simply, is the absence of belief in any deities. This view is ordinarily contrasted with theism, the belief in one or more deities. A third position, agnosticism, which claims to be a position of skepticism by which an individual claims not to know whether a deity exists and is unwilling to make a statement one way or the other. Agnosticism is attacked by atheists who claim that it is not a philosophically valid position to hold as one either believes something, usually when positive evidence is provided for such belief, or one does not believe, meaning there is no evidence to encourage belief. Theists and self-styled agnostics often claim that atheism is not philosophically justified, since in the absence of positive evidence against the existence of a deity the rational position is admission of lack of knowledge one way or the other. Atheists, on the other hand, contend that the rational default position in absence of evidence is disbelief. In discussing this debate it is necessary to narrow the parameters to the discussion as it is conventionally portrayed and analysed, meaning that the debate will take place largely within the parameters of the Abrahamic religions (Islam, Christianity, Judaism), since atheists most often come from the developed world where these religions predominate. These religions share many of the aspects attributed to deities, and thus can be discussed together. Trying to bring in non-monotheistic religions, such as Hinduism or Zoroastrianism would entirely alter the debate, since they would revolve around very different conceptions of life, morality, goodness, the Universe, and the supernatural. Thus this debate will keep its focus on the narrower, Abrahamic conception of God and the justifications for atheism stemming from it. Debates on the issue of atheism’s validity centre around the philosophical justification for atheist belief and the empirical, philosophical, and logical evidence for and against the existence of a deity and for the truth of atheism.
Physics and cosmology explain the development and evolution of the Universe and the bodies within it. Chemistry explains the interactions of substances and the origin of life. Biology explains the development of life’s complexity through the long process of evolution. God, or gods, is a superfluous entity in the discussion of existence; He is entirely unnecessary to human scientific understanding. At best, believers can point to various missing links in science’s explanation, using God to fill the gaps. The God of the Gaps is a weak God whose domain grows smaller each day as science progresses. Furthermore, there is no evidence of the supernatural existing at all, if that is what God is meant to be. The burden of proof in a debate concerning the existence of something is on the individual making the positive claim. In a debate over the existence of God, it is up to the believer to provide evidence for that belief. The rational position in the absence of evidence is atheism. It is not a positive claim about anything, but is merely the absence of belief in God, which makes sense in the light of there being no positive evidence of God’s existence. If believers claim God lives outside the Universe, or that He cannot be empirically identified due to His ethereal nature, then in truth they are saying nothing. Only the natural world exists insofar as humans can demonstrate. The supernatural is pure fantasy.
 Boyer, Pascal. 2001. Religion Explained: The Evolutionary Origins of Religious Thought. New York: Basic Books.
 Russell, Bertrand. 1952. “Is There a God?” Campaign for Philosophical Freedom. Available: http://www.cfpf.org.uk/articles/religion/br/br_god.html
Science cannot explain everything. People have spoken of the existence of the soul and of God through the ages because reason and logic are sometimes not enough to explain the complexity and depth of the human experience. God is far more than the occupier of the gaps in scientific knowledge. However, the gaps are indicative of the limitations of science and show that faith and God can still have a place in human comprehension of the world.
If God, or the gods, were good there would be no evil in the world. Disasters would not kill millions of innocents, disease and hunger would not claim the lives of children every day, war and genocide would not slaughter people indiscriminately as they have done for countless bloody millennia. The world is awash with blood, pain, and suffering. No loving God would make a world so imperfect and troubled. The world’s ills are perfectly explained by the natural, amoral development of the Universe, of life, and of humanity. The reality of the Universe, however, is incompatible with a God of goodness, as He is conventionally described by today’s predominant religions, which stem from the Abrahamic tradition.
Evil may be thought of as the absence of good. It is a privation of goodness, just as darkness is the absence of light. God is good and the embodiment of goodness, but humans have been endowed with free will; they can make the choice not to follow the path of good. People have the ability to make both good and bad choices; if they did not then they would not truly be free. God’s greatest gift to humanity is thus also a heavy burden.
 Kekes, John. 1990. Facing Evil. Princeton: Princeton University Press.
Many people do not believe in God, and the ranks of atheists are growing every day, particularly in the developed world. It seems that as human knowledge of the Universe expands and as social institutions develop and improve, people feel less dependent upon the crutch of religious faith, and place greater store in reason. If God existed He would make His existence clear to all humanity, not just to a chosen few. In so doing His wisdom would naturally drown out an earthly knowledge, which would obviously be inferior to any that might be furnished by an omniscient being. God has clearly never imparted His wisdom to people since no such divine wisdom exists in any holy book. Were there a correct holy book currently in use, it would necessarily be the only one, because everyone would acknowledge its superiority at once. Reality shows all holy books to be flawed works of flawed men. There is no glimmer of divine spark in any of them, and the only thing that separates most of them from the ravings of madmen is that large groups of people have chosen to believe them. The more reasonable conclusion is one of atheism, and that people believe in God out of ignorance, not revelation.
 Drange, Theodore. 1998. "Nonbelief as Support for Atheism". Twentieth World Congress of Philosophy.
 Schellenberg, John. 2005. "The Hiddenness Argument Revisited". Religious Studies 41.
It is unreasonable to suggest that God must reveal Himself to humanity, or to make His existence manifestly clear because that would undermine the value of faith. Belief is an important component of all religious teachings because it is what allows the soul to transcend the material world and to commune with the divinity. For the religious, a life without faith is meaningless. Furthermore, if God were to make His desires and commands known, then free will would be undermined. It is necessary to the exercise of individual human agency that God not dictate every command to people. That is why God leaves life, at least on the surface, up to humans.
 Maitzen, Stephen. 2006. "Divine Hiddenness and the Demographics of Theism". Religious Studies 42.
A creator god is a logical absurdity, as demonstrated by empirical fact and rational reflection. Certainly God cannot exist outside of the Universe, as such a concept is effectively meaningless. In fact, physics explains that when the Universe expanded as an inflating field of space and time as the result of a quantum fluctuation, causality itself arose from the process, making a causative agent “prior” to the Universe not only unnecessary, but also impossible. Furthermore, the idea of an omnipotent God is logically contradictory because if God were omnipotent He would be able to create an entity greater than Himself, yet that is impossible. The very attribute is logically unfounded, making the conventional explanation of God invalid. Thus atheism, the absence of belief in gods, is the only logically justified theological position.
 Savage, C. 1967. "The Paradox of the Stone". Philosophical Review 76(1).
Just because God cannot be understood by conventional understandings of physics and logic does not invalidate His existence. In fact, it is unsurprising that trying to discuss the attributes of God would confound human reason. That is why faith is essential to understanding, and why science and reason are limited tools. Thus even if one considers the conventional description of God to be unsatisfactory, it is not sufficient reason to conclude that God does not exist. That is why one should at best adopt a position of agnosticism.
God, like unicorns, has never been shown to exist, and thus it is logical to accept that He, just like unicorns, does not exist. That is why a position like agnosticism makes no sense. There are no agnostics on the subject of unicorns; there are only agnostics on the subject of God because people tend to be reticent to say they are atheists due to the prevalence of belief of God even in the most secular societies. But fantasy is fantasy, and an agnostic is really just an atheist by another name. Were someone to claim that dragons exist, the person he told it to would not be justified responding saying he did not know whether they exist and that it must be an open question until evidence is presented to corroborate the claim. Rather, he would likely respond with disbelief in the absence of evidence. That is how reasoning works. Thus agnosticism is a philosophically meaningless position. There is either belief or lack of belief, atheism or theism. Opponents of atheism seeking to hide in the nebulous realm of agnosticism, or who claim that because one cannot know there is no God one must be agnostic, hold a position that is philosophically bankrupt.
 Dawkins, Richard. 2006. The God Delusion. Ealing: Transworld Publishers.
There is no strict dichotomy in theology. It is perfectly reasonable for someone unsure of whether God exists to take up a position of agnosticism, refusing to emphatically accept the existence of God or to deny it. Atheism is a positive claim insofar as it is a statement about the nonexistence of God. The burden of proof is thus not so clearly on the shoulders of theism alone. Rather, they are rival claims that each side must be supported by positive evidence.
The reason people believe in God and why religions have formed can be explained perfectly well by natural processes and psychology. Religion is an outgrowth of humans’ brain architecture developed through the process of evolution; it developed as a by-product of other useful cognitive processes. For example, survival capability is promoted by an ability to infer the presence of potentially hostile organisms, the ability to establish causal narratives for natural occurrences, and the ability to recognize that other people are independent agents, with their own minds, desires, and intentions. These cognitive mechanisms, while invaluable to human survival and communal development, have the effect of causing humans to imagine supernatural purposefulness behind natural phenomena that could not be explained by other means. No gods are required to explain religious belief, so the existence of such belief is no reason to believe in such beings. Religion was a cradle during mankind’s childhood and adolescence. The time has come to grow up as a species and accept that there are no gods.
 Henig, Robin. 2007. “Darwin’s God”. The New York Times. Available: http://www.nytimes.com/2007/03/04/magazine/04evolution.t.html?pagewanted...
 Pinker, Steven. 2004. “The Evolutionary Psychology of Evolution”. Annual Meeting of the Freedom from Religion Foundation. Available: http://pinker.wjh.harvard.edu/articles/media/2004_10_29_religion.htm
Not everything about religion can be explained by evolutionary psychology. The existence of the soul and the concept of an ethereal God not directly connected to the processes of the world could not simply come about by way of evolution. Rather, there must be true meaning in these concepts, or they must at least be indicative of something other than the strictly material, contradicting the denials of atheism.
It seems as if life goes on whether God exists or not. Theologians, philosophers, and laypeople have been fighting both in academia and on the actual battlefield over the question of God’s existence, yet in all the centuries no definitive answer one way or the other has been given by either side. It seems there is little value to belief one way or the other, so arguing for God’s existence seems simply to be a waste of time. If God were proved to exist, or not to exist, little in life would change at all. Thus a position of atheism serves to relieve the hassle of pointless debate.
 Borne, Étienne. 1961. Atheism. New York: Hawthorn Books.
The question of God’s existence does matter, not only to those who believe, but to understanding of life and its meaning. If there is a God and He has a plan for humanity and the Universe, then in order to understand the plan and to become an active part in it, one must try to understand in some sense the nature of God. However, even if God were disinterested in His creation, that would do little to affect whether He exists or not.
In a situation where there is an absence of either positive evidence for a claim or definite negative evidence for it, the natural response is not rejection of the claim, but rather skepticism and admission of lack of knowledge one way or the other. In the case of religion and God, this position is agnosticism. Humans are fallible organisms, and thus all statements about truth and about the Universe must be qualified by some degree of doubt. Positively rejecting the existence of God, as atheism does, ignores this requisite doubt even though it cannot prove that there is no God. Rather, in the absence of evidence for or against the existence of God, the most the atheist can say honestly is that he does not know. The claims of atheism are positive ones and thus require evidence; an atheist position is thus faith-based in the same way a theist one is.
 Hume, David. 1748. An Enquiry Concerning Human Understanding. New York: Oxford University Press (2008).
The rational position in the absence of positive evidence about God is not agnosticism, but atheism. While there is always a degree of doubt in every statement, this does not mean that negative claims about an entities existence can never be made. One can rationally state that fairies do not exist, even if there is no positive evidence for their non-existence. The very fact that no evidence exists for the existence of fairies, in the same way there is no evidence for the existence of God, is evidence of the negative. Thus, in the evidence of positive evidence for God, the rational default position is atheism.
Atheism suggests that the Universe came about by chance and the interaction of natural properties. Yet nature is marked by clear design that atheism cannot explain. The complexity of the human body, of planets, stars, and galaxies, and even of bacteria attests to the existence of creative agency. It is impossible that such things as interdependent species could come to exist without the guidance of a higher power. Likewise, certain organisms can be shown to be irreducibly complex, meaning that if one were to remove any part of it, it could not function. This refutes the gradualist argument of evolution, since there is no selective pressure on the organism to change when it is functionless. For example, the bacterial flagellum, the “motor” that powers bacterial cells, loses all functionality if a single component is removed. Besides design, the only explanation of its development is blind chance, which seems less sensible. Atheism cannot account for these facts and thus collapses into nonsense.
 Ratzsch, Del. 2009. "Teleological Arguments for God's Existence" The Stanford Encyclopaedia of Philosophy. http://plato.stanford.edu/entries/teleological-arguments/
 Davis, Percival and Dean Kenyon. 1989. Of Pandas and People: The Central Question of Biological Origins. Richardson: Foundation for Thought and Ethics.
Atheism does not seek to explain the origin of the Universe, life, etc.; that is what science is for. Atheism is about the existence of God. The atheist position is supported, however, by the fact that there is no evident design in the Universe. People tend to anthropomorphize their environment, trying to assign human-like qualities to animals and nature. All of the complexity in the Universe can be attributed to natural processes; the Universe, stars, and life are all the product of physical and chemical interactions. There is no mystery in the basic process. Complexity can be shown to arise from less complex conditions without aid of intelligent agency. Clearly, complexity is not indicative of a creator. The complexity of the Universe does nothing to support claims for the existence of a deity, but rather showcases the wondrousness of the natural world.
Every human, every being, every object in the Universe is a finite and contingent being. These all have causes, yet a causal chain cannot be infinitely long. Humans are born, stars form from gases, even the Universe had a beginning 4.3 billion years ago. Nothing in the Universe causes itself. In order to escape the logical impossibility of the infinite causality loop it is necessary to posit the existence of an uncaused cause. This cause exists outside of the Universe, as it is cause of the Universe. Without a creator, the Universe is a logical absurdity. Atheism cannot provide an alternative explanation to a creator, and thus fails quite literally from the beginning.
 Craig, William Lane. 1979. The Kalam Cosmological Argument. London: MacMillan.
If everything has a cause, then so too must the creator. Trying to place the deity outside of the spatio-temporal realm of the Universe is not a good argument, as nothing can be said meaningfully about what is “outside” the Universe, since we cannot observe or detect it. Furthermore, saying God, or a creator, is uncaused and always existed is a poor argument because again this cannot be verified in any meaningful way. Irrespective of these problems, however, the argument falls down because it presupposes that the Universe has a cause, which is not necessarily the case. The very notion of causation is built into a temporal understanding of physics, which may not have been the case in the “pre-Universe”. Atheism can survive in the presence of science, theism cannot. If theism cannot survive, then neither can the agnostic middle ground based on the plausibility of theism.
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