Credits: Although the large majority of this FAQ originates with the author, some of the comments here were copied from Associate Professor Matt McCormick's atheism blog.
The gods of theism or deism are gods for which the phrase "god intentionally or knowingly or deliberately did it" applies. I am an atheist because in my view such god belief is unjustified.
A belief in a fact claim is justified by explanatory utility, which is rooted in evidence, and by explanatory validity, which is rooted in logic.
A valid explanation is a hypothesis that identifies a causal relation between some observed/known fact(s) being explained and the hypothesis. Just as importantly, the explanation should be incompatable with contradictions to the same observed/known facts. Thus valid explanations must distinquish what is true from what is false.
Not all claims make any sort of true or false difference in the world. No state of affairs would count against them. They are expressions of personal desires, hopes, or feelings. They aren't a matter of true or false, or even of right or wrong. The problem is, of course, that lots of people who are making these claims do not think that what they are doing is non-cognitive. They think that Jesus really did die for your sins, and that Jesus really does love you, and that those clichés actually mean something. It can be hard to dismiss such claims as non-cognitive when the speakers themselves insist that they are making true assertions that make all the difference in the world. The real measure of whether or not some claim is cognitive is not determined by how the believer feels about it. The believer may not appreciate the non-cognitive nature of what they are claiming.
God is a vacuous catch-all declaration that is intrinsically unable to identify what must be false. In my view, gods function as a magic carpet that theists sweep all of our ignorance under. Theists then convince themselves that they have in some sense dispelled our ignorance and found an essential aspect of the ultimate truth when in fact all they have done is sweep our ignorance under a rug. Also, many theists consider gods to be an inherently unexplainable mystery, beyond human understanding, an unknown. Such mysterious gods have no explanatory power because it can only provide "understanding" for phenomena in terms of the unknown (itself). Theistic religionists usually claim that both religious belief and science are compatable, non-overlapping or overlapping, alternative valid methodologies for finding literal (as opposed to merely fictional metaphorical) truth. Most atheists consider such religionists to be mistaken, we consider religion to be invalid as a methodology for understanding reality (and unecessary for enriching our lives with metaphorical "truth"). Read my short essay "God" Has No Explanatory Power for a more detailed argument.
For more information on this important topic try ON THE JUSTIFICATION OF BELIEF AN INTRODUCTION TO EPISTEMOLOGY FOR SKEPTICS by William A. Wisdom (excerpt below). and Methodological Naturalism and Philosophical Naturalism: Clarifying the Connection by Barbara Forrest (excerpt below).
To explain the occurrence of a particular event Y by saying that event X caused it is at least to say that (a) event X occurred before Y, and (b) our experience shows that whenever an event like X occurs, it's followed by an event like Y. So in order for appeal to the creative power of God's will to count as explaining the origin of the universe, we'd have to have lots of experiences of God's wanting a universe, followed by the appearance of one. But of course nothing of the sort is the case. The believer might say that we do have relevant experiences, but of a different kind: we have experiences of semi-potent wills bringing things about, God is omnipotent, and so we know what it means to say that God always gets what He wants--that's the requisite "law". But while we may know what this means, we have no reason to think that it's true. That is, we have absolutely no reason to believe that there is a general principle (or, for that matter, an antecedent state of affairs) of the sort needed for an explanation in this case. One who says that God created the universe is saying exactly this: I have no idea how the universe came into existence. William A. Wisdom
Since the claim that methodological naturalism is compatible with anything other than philosophical naturalism requires the so far indefensible claim that there are an additional but logically compatible methodology and epistemology, the fourth possibility constitutes the only viable relationship between methodological naturalism and philosophical naturalism, which is this: Taken together, the (1) proven success of methodological naturalism combined with (2) the massive body of knowledge gained by it, (3) the lack of a comparable method or epistemology for knowing the supernatural, and (4) the subsequent lack of any conclusive evidence for the existence of the supernatural, yield philosophical naturalism as the most methodologically and epistemologically defensible world view. Barbara Forrest
Religious beliefs are rooted in assertions about the way the world is. Such beliefs are therefore fact claims that require supporting evidence to justify the beliefs. Theists sometimes cite faith, but faith by itself is belief without evidence which is unjustified belief. Reason is prescriptive. When there is compelling evidence in front of us and we understand it, and it is clear that it implies a certain conclusion, then we ought to believe that conclusion. Faith is not prescriptive. A believer by faith has no grounds from which they can argue that others who don't have that faith ought to. They can't properly criticize the non-faithful for doing something contrary to reason or ignoring the evidence by not believing. An excellent discussion of this important topic can be found in The Ethics of Belief, Essays by William Kingdon Clifford, William James, and A.J. Burger.
A classic valid form of argument is modus tollens (Latin for “mode that affirms by denying”): If T then there should be evidence ET for T. There is no evidence ET for T (as far as we have been able to determine to date). Therefore T is probably false. Modus tollens can be utilized deductively to prove a conclusion or it can be utilized inductively. Deductive reasoning progresses from general evidence to a particular truth or conclusion; whereas induction starts with a particular observation that is believed to be a demonstrative model for a truth or principle that is assumed to apply generally. We can also argue for atheism inductively this way: If A then there should be evidence EA. The evidence is EA. Therefore A is probably true.
It is commonly argued that the non-existence of gods must be "proven" to justify atheism and that negative propositions such as atheism cannot be proven and therefore must be rejected. A God defender can always rejoin that God is reclusive and invisible and can only be found by opening your heart to Him. You can’t prove God doesn't exist! The problem here is that deductive proofs have little if any practical applicability to most debates outside of narrow contexts, such as mathematics and logic, so we must rely on inductive arguments. However, inductive arguments don’t give us certainty about anything at all. All observed swans are white, therefore all swans are white looked like a pretty good positive inductive argument until black swans were discovered in Australia. No inductive argument will conclusively, indubitably prove a proposition beyond all shadow of a doubt. The very nature of an inductive argument is to make a conclusion probable, provided the premises are true, and that is the best result anyone can reasonably expect from any debate regarding the existence of anything whose existence has not been empirically proven and whose existence isn't logically impossible.
However, it is a big mistake to dismiss induction because we’re not getting certainty out of it. Why do we think that the sun will "rise" tomorrow? Not because of observation (you can’t observe the future!), but because that’s what it has always done in the past. Why do we think we will find our house where we last left it? Because that’s the way things have always been in the past. In other words, we use inferences — induction — from past experiences in every aspect of our lives to decide both "absent" and "present" facts about the world that we depend on, and such induction from the evidence, unlike simple faith, is a productive and valid method for justifying such beliefs.
Adopted from "God: The Failed Hypothesis. How Science Shows That God Does not Exist." Stenger, Victor J., Amherst, NY: Prometheus, 2007. p. 231++
But none of this happened. The hypothesis of God is not confirmed by the data. Indeed that hypothesis is strongly contradicted by the data.
Claims of fine-tuning have generally been based on what happens when we vary a single characteristic of the universe, such as the strength of gravity, while holding all others constant. A recent simulation by Fred Adams, University of Michegan, suggests that contrary to some previous claims, stars are not only common in our cosmos but are also ablaze in myriad other universes where the laws of physics may be drastically different. Under this simulation, the gravitational constant, the fine structure constant ("alpha"), and the number that determines the rate of nuclear reactions (which is a composite of constants that keeps stars shining) were varied. Stars were stable in about one fourth fo the universes considered. "You can change alpha or the gravitational constant by a factor of 100 and stars still form," Adams says. We do not know if all possible values of each parameter are equally likely, but this result does suggest that the fine tuning argument becomes much weaker when the constants are varied together instead of individually.
Most of our universe is highly hostile to life. We have no reason to assume that ours is the only possible form of life and perhaps life of some sort would have happened in a universe that took various other forms. The Multiverse hypothesis posits the existence of many universes with different physical constants, some of which are hospitable to intelligent life. Because we are intelligent beings, we are by definition in a hospitable one. Some versions of Big Bang theory incorporate a multiverse. For example, in inflationary theory, a rapid expansion during the first tiny fraction of a section may have occurred in multiple patches of space, creating a multitude of universes. Finally, even assuming there is a single universe that is fine tuned for life, its not clear how positing god(s) resolves the paradox since that hpothesis smiply relocates the focus of how the universe is tuned for life from the physical constants having particular values to the presence of god(s) whose purpose is to create us.
Whether any gods exists and whether it is justified to believe gods exists are related, but nevertheless distinct questions. Only the latter question is accessible to rational discussion. As an explicit atheist I say that I believe there are no gods. Implicit atheists, following Thomas Jefferson's advice quoted below, prefer to say that they don't believe in god(s). All atheists share the view that belief in any god(s) is unjustified. Many, but not all, atheists are philosophical naturalists. Philosophical naturalism rejects supernaturalism. We use the philosophical qualifier to clarify that we are not claiming to be experts in zoology or botany which is a different definition of naturalist. Technically, all nontheists are to some extent both agnostic and atheist because they are overlapping, context sensitive concepts as argued in Atheist or Agnostic? by Richard Carrier, February 1, 2007.
Ignorance is preferable to error, and he is less remote from the truth who believes nothing than he who believes what is wrong. Thomas Jefferson, 1782
The fact that a claim is merely possible does not give us sufficient reason for thinking it is true. This is because the number of claims that are "possible" yet false appears to be infinite. It is possible that the earth rests on the back of an invisible turtle. It is possible that lightening is thrown by an angry Zeus. It is possible that aliens conspired with Oswald to kill JFK. It is possible that tossing spilt salt over your shoulder improves luck. Atheists consider god(s) to be one more item on that possible but so far-fetched that it merits being considered false list (unlike theistic leaning agnostics who consider the god concept to be plausible enough to take more seriously).
Some people consider it a useful and challenging project to devise new and more inventive, "sophisticated", descriptions for gods that are more resistant to counter arguments. However, at best, this only addresses the hypothetical: If there were gods then this is what gods could be like. Hypothetical gods are not real just because we can derive some vague, general, or abstract account that isn’t obviously contradicted by evidence. There’s still the question of supporting evidence — what are the grounds for believing such gods are real? The gods concept becomes less meaningfull, and therefore the grounds for gods beliefs arguably becomes weaker, as the definitions for gods become more vague, general, and abstract.
The less sophisticated, but more common, "God’s nature is beyond our comprehension" responses to criticisms that various commonly held conceptions of gods conflict with facts about the world are actually counter-productive. Such defense-by-ignorance arguments give us even more reason to think that believing is not reasonable or supported by evidence.
It is helpful to compare sense perception (SP) with religious experience (RE) to illustrate why RE is relatively untrustworthy. Since a RE, if real, would be freely brought about by divinity, there is no way to predict who will have such an experience and under what conditions. It is for this reason that RE is 'private'. In contrast, for SP we are able to predict who will have the perceptual experience in question and we are able to predict future events that will confirm the veridicality of a given experience. We can make successful predictions and thereby control events by using SP and we can establish facts about how SP works that indicate that SP is generally reliable, why it is reliable, and the special circumstances under which SP is less reliable. RE does not exhibit self-support in any way that is analogous to the self-support SP exhibits. Unlike SP, it is impossible to disconfirm the veridicality of a RE by appeal to the testimony of other observers.
Private religious experiences are merely mental events, and there is therefore no logical problem with our having these experiences without the world being as they represent it to be. We could readily doubt our own religious experiences, asking “Was I hallucinating?”, “Am I putting my own interpretation onto something mundane?”. Religious experience does not prove anything objective about the world.
There is a wild diversity of perceptions of communications from god(s) with many being mutually inconsistent. The reports people give as to what god told them could not possibly all be true unless god is incredibly confused, vacillating, or inconsistent. Many pairs of alleged communications are such as to evince radically incompatible divine attributes. The tests for veridicality employed within the different religious traditions are mutually incompatible.
People can have experiences of emotions, thoughts, sensations of movement, and the like that they interpret as having external origin even though the origin of these experiences may be internal. Alternatively, there may be an external stimulus for an experience but the external stimulus is different from the internal representation or the subjective interpretation. There is simply no evidence that the experiences people interpret as god experiences are the result of god(s). Imagine a doctor telling you that she's got self-authenticating evidence that you've got cancer, but the evidence can't be grasped by anyone who doesn't already believe it. Or imagine your spouse telling you that there is special, private, self-authenticating evidence that you've been cheating by carrying on a secret affair with someone else. "Evidence" that's private isn't really evidence at all and a mere feeling that something just must be true, no matter how strong or persistent, is never enough to give it warrant.
To put this another way, beliefs can be drivers. They can drive our thoughts and our dreams and our emotions. People can self-generate emotions and thoughts in accord with their religious beliefs. This tendency, called "confirmation bias, " has been well studied and documented by sociologists and by the historical record that reveals that polytheists and monotheists throughout history have claimed first hand experiences of witnessing their different and mutually incompatable gods. From this perspective, religious experiences, although genuine, are belief driven and the interpretations of those experiences as evidence for gods, while sincere, are nevertheless mistaken. Conversely, emotions can drive our beliefs and emotions and beliefs can interact to reinforce each other. It is common for widowed people to experience the presence of their deceased spouse, sometimes in the form of visual, auditory, or tactical hallucinations, known as "bereavement hallucinations". Auditory hallucinations, and in particular the hearing of a voice, are characteristic of people suffering from schizophrenia.
For an example of how our minds can play tricks on us read Night of the Crusher and Abductive Reasoning book review by Chris Mooney
When Buddhist monks meditate and Franciscan nuns pray their single photon emission computed tomography (SPECT) scans indicate low activity in the posterior superior parietal lobe (PSPL), a bundle of neurons whose job it is to orient the body in physical space (people with damage to this area have a hard time negotiating their way around a house) by distinguishing between self and non-self. When the PSPL is underactive that division breaks down, leading to a blurring of the lines between reality and fantasy. Maybe such changes in mental activity help to explain why monks feel a oneness with the universe and nuns feel the presence of God.
Psychological studies make clear that many humans possess a powerful epistemic, and emotional craving for a causal explanation for everything we encounter. When test subjects are confronted with puzzling, random, or unexplained sequences of events they spontaneously form hypotheses about a causal relationship between them. They provide causal explanations even when none are apparent, they infer them even when not instructed to, and they remember described scenarios by means of causal cues better than by non-causal memory cues. And in the case of pain, we have an additionally powerful subconscious motive or urge to explain it away in some fashion—it will literally feel less painful if we do. Natural selection may have endowed us with a sort of mind-attribution module. Construing other organisms behavior as the product of the planning and goals within their minds, whether they really have them or not, can be an effective mechanism for anticipating and projecting the behaviors of potential predators and prey. We're built to take this too far and endow everything with a mind—the wind, the ocean, the starry sky, and the world itself. Belief in gods helps to satisfy this “everything happens for a reason” sentiment.
Inflationary big bang and the cyclical universe models, which are amply supported by the data, predict a close balance between positive and negative energy such that the total energy of the universe is zero. Thus, no violation of conservation was required to bring the matter and energy of the universe into being. The universe began in a state of maximum entropy and the total entropy of the universe has been increasing ever since! This apparently contradictory state of affairs is explained by the fact that the universe is expanding, with the maximum possible entropy of the universe growing faster than the total actual entropy. Thus, the universe only appears to be getting more ordered, but this is only because there is more room to spread out the clutter.
The frame of reference which posits that we must start with nothingness and then add an external cause to get from that default state to a state of somethingness is not the only possible frame or even the most likely frame. The laws of physics suggest that nothingness could be an unstable state that eventually undergoes a spontaneous phase shift to a state of somethingness. Indeed, a state of continuous nothingness may be so improbable that it would require divine intervention to maintain. At least some cosmologists appear to think it is plausible, if not more plausible, that the uncertainty, non-determinism, and resulting spontaneity that describe and characterize our universe are also necessary components of an explanation for the existence of our universe. In short, no miracle, and hence no creator, is needed to explain the features, origin, existence or current state of the universe.
Who knows and who can say, whence it was born and whence came this creation? The gods are later than this world's creation. Who knows then whence it first came into being? "Nasadiya" verse of 3,500 year old Rig Veda
Based on reading science news for some years and discussions with various religious people, it is my judgement that some religious people have a tendency to underestimate the capability of exclusively naturalistic processes to produce such phenomena. Astronomy and cosomology reveal a world where earth and its solar system are insignificant and non-special and paleobiology reveals a world where singled celled life predominates and multi-celled life first appeared relatively recently with vertebrates first appearing long after invertebrates first appeared. This doesn't suggest a world that is designed and organized by a superior intelligence. Nor was any of today's knowledge known in advance by the authors of the ancient holy books as we would expect if those holy books were the words of all knowing creator gods.
Religionists have become adept at constructing ad hoc explanations to accept new discoveries when this is necessary to avoid conflicts with their religious beliefs, sometimes after strenuously resisting the truth. That their worldview previously contained no indicators of what is now taken to be obvious because of what science has forced them to accept is conveniently written off as metaphor, discounted, neglected, or forgotten. "Adam and Eve? Oh, we never really believed that literally." "The earth is only 6,000 years old? That's so quaint-it isn't what we really believe." All of the ad hoc re-engineering and gymnastics in order to salvage an Iron Age ideology is intellectual dishonesty when it is clear that the space left for the gods of the gaps is rapidly shrinking. If the intelligent design hypothesis about God's interventions in evolutionary history is correct, then why did no religious source ever give any indication of it until the 1990s? If the abundant amounts of apparently pointless suffering and death in the world has always been part of God's plan to build moral character, then did we not get any indication that this was true from religious sources until after atheists like William Rowe argued that pointless evil is evidence that there is no God? If viruses, not evil demon possession, were the source of disease all along and part of God's plan, then why has religious doctrine always been so clearly in favor of demons?
Gods are strangely stingy about sharing any of its knowledge. If the four fundamental forces—gravity, strong, weak, and electromagnetic—are all God's means of constructing the universe, then why can't we find any indication of that anywhere in any religious doctrine or tradition before physics discovered them? If evolution was the method whereby gods brought life into the universe as so many Americans now believe, then why can't we find even the slightest hint of it in any religious source or the word of gods prior to Darwin's hard fought battle with those same believers? If there are Higgs-Boson or graviton particles, then why have gods not told us about them? Why haven't gods provided us with a clear, developed picture of the origins of consciousness? How come the holy books don't inform us about the prevalence of life in the universe at large or how it got started? If gods have good reasons for making its presence hidden then why do we have good reasons to believe that gods exist?
We have a general responsibility to be honest about what we don't know and not pretend to know more than we do. If gods exist then these gods' existence, no less than the existence of the universe, life, etc. also requires explanation. Gods as Creators would have to be more complex than our universe itself because such gods supposedly knew everything required to design and create our universe, knowledge that a designed universe itself would not have. Resorting to such Creator gods is tantamount to "explaining" a complex mystery by postulating a more-complex mystery. Gods beliefs introduces a supernatural realm in addition to the natural realm. The supernatural realm concept is an inherently unconstrained catch-all and as such cannot be disproven. So gods beliefs complicates (it tends to undermine) the pursuit of explanation. We have learned more about the universe, life, consciousness, spirituality and the like as a result of the past 100 years of scientific investigation than is found in any religious book or doctrine.
To seek a final answer is to hope that everything beyond that is incomprehensible. And since that move is always available to shore up any false theory, it must be a mistake. David Deutsch
To summarize:
Without belief in gods, the argument goes, we would be immoral and therefore it is important to "believe in belief", as Daniel Dennett puts it (Breaking the Spell). It would produce better, more moral results if we were to believe something false or unsupported because otherwise our natural tendencies, which are wicked and depraved, will win out. Hidden in that argument is the assumption that we are capable of figuring out what is right and wrong and acting in accord with it without any reference to gods all along. After all, how can we know that we are naturally wicked and depraved without an innate sense of what is right and wrong? And how can we justify religious belief on the grounds that it produces better moral results without appealing to some pre-existing desire to realize a more moral result? Actual evidence that non-belief in gods correlates with unethical behavior is missing or weak. For example, Morality without religion (PDF format) was a three question survey on ethics by Marc Hauser and Peter Singer that found no difference between atheists and people with religious backgrounds and beliefs.
When religion is sensible regarding behavior and ethics, such reasonable guidelines then stand on their own without God. But when religion doesn't make sense, as too frequently is the case, it carries its own, special, irrefutable form of dogmatism and irrationality. Belief in God can justify what can't be justified on rational grounds with an unearned authority and finality. "God wills it", like "God did it", has no substantive content: it can be used to endorse almost anything. Calling on the gods is a handy device for legitimating moral positions, but it can legitimate anything. It discourages questioning instead of providing a real answer.
Moral behaviour is the sort of thing we should expect from sufficiently complex social animals. Morality and the Social Instincts: Continuity with the Other Primates by Frans B. M. De Wall and The Moral Instinct by Steven Pinker discuss this. Asking for some kind of ultimate justification for moral behaviour makes about as much sense as asking for an ultimate justification for breathing or sweating. Explaining moral behaviour in biological terms doesn't provide any kind of ultimate justification for morality. Theisms and religions don't either (although they like to claim otherwise). The mistake is to assume that morality needs such ultimate justification in the first place.
Philosophical naturalism provides us with the best explanation of what we are doing when engaging in various discourses. But this naturalistic understanding does not substitute for these discourses. It does not, in particular, require us to assimilate mathematics, ethics and so forth into a generalized scientific enterprise for much the same reason that engineering, while not working with anything supernatural, is not a mere extension of science. For one thing, there is no such thing as The Scientific Method. More important, we have multiple aims in life, and we cannot expect all our aims to be served by an enterprise devoted to explaining how the world works.
Atheists are people who think inquiry and doubt are essential checks against deception, self deception, and error, that logic and proper empirical method is the only way the whole world can arrive at an agreement on the truth about anything, and that it is better to be good to each other and to build on what we all agree to be true, than to insist that we all think alike. What an Atheist Ought to Stand for by Richard Carrier
One reason I might adopt the moral point of view is that I feel that, as a human being, I have no more and no less rights than anyone else, and that everybody else is just like me in this respect. I can think of nothing that essentially or intrinsically distinguishes me from anyone else so far as rights and obligations go, even if I am stronger or smarter or richer or taller or whiter than some other people. MORAL RELATIVISM vs. ABSOLUTISM, MORAL SUBJECTIVISM vs. OBJECTIVISM, AND THE WILL OF GOD by William A. Wisdom.
With or without religion, you would have good people doing good things, and evil people doing evil things. But for good people to do evil things, that takes religion. Steven Weinberg
Here is a draft version of Bright Movement's assertions about morality that they claim are backed by scientific studies. The Bright Movement defines a bright as "a person who has a naturalistic worldview." The movement's three major aims are:
A common agenda of some atheists is as American as apple pie: Upholding and promoting government nuetrality, which some religionists whose beliefs are currently in the majority find objectionable and mischaracterize as government bias against their beliefs.
Many atheists have no self-generated inner motivation to engage in worship or consider as holy or divine, and thus maintain a religion based on, any human authored fictional metaphorical "truth" found in religious literature or practices, However, some atheists will attend church sponsored events, or even more actively participate in the religious worship and practices of others, as participants in various social groups that have some form of religious based identity. Like all humans, atheists are social mammals and they may have relatives or friends who are religionists. This does not mean that atheists can be expected to participate in religious worship and practices. Atheists are entitled to openly and publically be themselves and many atheists, like many theists, do not like to be pressured into either publically expressing beliefs they do not hold nor hiding or publically revealing the beliefs they do hold.