Tuesday, July 14, 2015

Why Do So Many People Believe in [a] God?

One argument I hear periodically is that, even if you can refute the claims of one particular religion, doesn't the fact that almost all cultures throughout human history have held a belief in some sort of god or gods mean something?  Couldn't this be evidence that there is, in fact, some sort of supernatural creative force "out there" and we all just perceive and interpret it in different ways?  If you want to get all scientific (and I always love when people invoke science to justify their non-scientific beliefs), doesn't it show that humans have evolved to believe in God and that it would only make sense if there were, in fact, a God to believe in?

Now, the easiest answer would, of course, be that it doesn't matter if a billion people believe something to be true if the thing is actually false, and humanity has collectively believed a lot of wrong ideas throughout history.  For untold thousands of years, people believed ("knew") that the sun went around the earth once a day, despite the fact that the earth actually revolves.  People believed that illnesses were caused by all matter of things (bad air, curses, etc.), despite the fact that they are actually caused by germs.  So yes, most cultures throughout recorded history have believed in some sort of supernatural creator, but (skipping the obvious problem that no two cultures could agree on what that creator actually was like) that doesn't really provide evidence that those beliefs are correct.

Having said that, however, I think the question does deserve a little more nuanced answer.  It's not enough to point out that people believe a lot of wrong things, since that doesn't mean that this particular belief is wrong (only that it could be wrong despite the fact that so many people have held it, or some form of it).  Instead, it would be helpful to provide an alternate explanation for why a belief in god or gods seems to be such an ingrained part of human nature.  Now, I'm not saying that I can conclusively provide the actual explanation, but I do at least have some thoughts as to one possible alternate explanation.  Someday I'll write a book on this subject and fill it with annotated footnotes to scientific studies and research, but for now I'm just going to go with a summation of things I have heard and read about, as well as my interpretation of what it all means.

Humans may not have evolved specifically to believe in God, but I think it's safe to say that our intellect and capacity to solve problems certainly evolved as a survival mechanism.  Rather than developing armored hides to protect ourselves from danger or razor-sharp claws to bring down prey, humans evolved the ability to anticipate danger to protect ourselves and to solve complex problems in order to figure out ways to obtain food.  When early man saw the tall grass swaying, especially in the absence of any evident wind, he realized it could still be caused by the wind but could also be caused by a predator stalking him.  If he assumed it's a predator and ran away, he lived to survive another day even if it really was the wind.  On, the other hand, if he assumed it was just the wind and it turned out to be a predator, well, he likely wouldn't live long enough to pass his genes to the next generation.  And thus, we evolved to see patterns even when they don't exist and to assume agency (i.e., that things are caused by mindful creatures) even when things happen by random chance.

Although this tendency to see patterns and assume agency was instrumental in allowing humans to survive and flourish throughout the millennia, it also brought along some baggage with it.  That's evolution for you.  Evolution allows species to adapt to changing environments and survive, but there's no guiding force to ensure that a particular adaptation is the "best" possible solution, only that it was better than other adaptations that did not enable a species to survive.  This is why we have eyes with built-in blind spots, appendices that serve no purpose and occasionally kill us by bursting and, sad to say, an intellect that assumes that every little bump in the night must be caused by some creature coming to eat us.

The problem is, of course, that our pattern-recognition skills are flawed.  Sure, they are good enough to help us survive, but they have also led us to see patterns where they don't exist and also ignore any evidence that contradicts the patterns we have convinced ourselves do exist.  If we, for example, see evidence of agency all around us, in the apparent design of the complex natural world or in stories of people being blessed after praying to one God or another, we are going to stick with our beliefs in those patterns even if the apparent natural design can be shown to have an alternate explanation or we hear stories about people who prayed and weren't blessed.  Psychologists call this "Confirmation Bias" and it simply means that, once we have made up our minds about something, we tend to accept any evidence supporting that belief and disregard (or ignore) any evidence that contradicts that belief.  And again, as a rough survival tool, confirmation bias served us well in the past.  The fact that 9 times out of 10 the swaying grass ended up just being caused by the wind doesn't matter if that 10th time ends up being a hungry predator, so it's better to just ignore the cases that don't fit the pattern and see the one case in your favor as proof that swaying grass means death is waiting to attack with sharp, nasty claws and fangs.

So, yeah.  Throughout history, human societies have tended to believe in one sort of supernatural force or another.  We don't know what that bright yellow thing in the sky is, but it moves and therefore must either be intelligent or else be pulled by something intelligent.  And when it hides for most of the day and things get cold, it must be because it is angry with us.  So we'd better pray to it and sacrifice things to it just in case.  And, sure enough, after a few months of prayers and sacrifices, winter comes to an end and spring returns proving we were right.  Except, we now know all about the rotation of the earth, the tilt of its axis and its yearly journey around the sun.  Does the fact that humans, in their ignorance, used to think the sun was a god and worshiped it accordingly really say anything about whether their is a god of some sort?  Or does it just speak to our ignorance and gullibility?

Wednesday, June 10, 2015

What Would It Take to Convince Me?

OK, so I've been watching more theist vs. atheist debates, and one question that often gets asked of both sides is "what would it take to convince you the other side was correct?" Typically, when the theists are asked what it would take to convince them that God doesn't really exist, the answer is that nothing could shake their belief in God. Which is, of course, rather telling, since it means that they admit their beliefs are neither based on evidence nor even rational to begin with, despite all their attempts to provide proof the existence of God.

Conversely, when the atheists are asked what would convince them of the existence of God, they usually start off by giving a snarky response along the lines of "a single shred of empirical evidence" and then say something like "if I looked up one night and all the stars had rearranged themselves to spell out a message saying, 'I am here.'"

Personally, however, I'm not sure a single bit of empirical evidence would sway me, no matter how impressive. Even if, say, somebody prayed to have an amputated limb restored and it grew back, I'd have to weigh that evidence against all the times when people prayed to have their limbs restored and it didn't happen.  And even if the single shred of evidence was overwhelmingly amazing, like the aforementioned message in the stars, I'd have to wonder whether I was hallucinating.

No, I think what would probably convince me more than anything else would be if the promises made in the holy scriptures actually and unequivocally happened on a consistent basis.  The Bible states repeatedly, for example, that if anybody prays for something in faith it will be given to them (not just that their prayers will be "answered").  The fact that most people don't actually get what they pray for, no matter how sincerely they believe, is just more evidence for the non-existence of God.  But if it were the case that Christians who prayed for things routinely received what they asked for (whether it be the health of a loved one, enough money to pay their rent, a safe trip, or even for a mountain to move from one location to another), I'd have to seriously consider the fact that maybe there's something to this whole God thing after all, despite how otherwise ridiculous it might seem to me.

Similarly, I'd be pretty convinced if faithful Christians routinely handled venomous snakes and drink poison with no ill effects as promised in the New Testament.  Sure, I know there are some fringe sects that do just this (well, they handle snakes, at least -- I'm not sure about the poison drinking), but the leaders have a tendency to die of snake bites after awhile...

Of course, believers will say that we shouldn't test God and that God purposely chooses not to reveal himself in such incontrovertible ways so as to not rob us of the ability to have faith in him.  To which I respond, "Then why did Jesus and his disciples make all those testable claims in the first place?"  I'm sure there are many other justifications why the things promised in the bible usually don't happen as promised ("God moves in mysterious ways", "the age of miracles is past", "it's all metaphorical", etc.), and that's fine.  The purpose of this post is not to point out the inherent inconsistency or hypocrisy involved, it's simply to state what would personally convince me that the God of the Bible actually exists.

Monday, June 8, 2015

Some Random Questions for Theists

OK, I've been watching some debates between theists (usually Christians) and theists again, and as usual I thought of a bunch of questions I really wish I had been able to ask.  I'm not saying these are unanswerable questions, especially since 2000 years of formal apologetics have allowed modern theists to come up with some sort of answer to just about anything thrown their way, but I'd like to think they are questions which would, at the very least, indicate the weakness of some of their positions and assertions.

  • Why do you keep asserting that the universe was "obviously" finely tuned to support life (and specifically intelligent human life), when 99.99999999... % of the known universe is utterly and completely hostile to the existence of life (let alone to human life)?  Is all the rest of the vastness of space just for the sake of decoration?

  • You've said that the observed suffering in the natural world is the direct result of mankind sinning in the Garden of Eden and causing the world (universe?) to enter into a fallen state with suffering and death.  If God is all powerful, however, why did he create a universe where man's sinning would affect all of creation and not just man?  Why would God punish innocent animals instead of just punishing mankind?

  • In the past, theists have claimed that the creation of the universe "out of nothing" proves the existence of God since there's no other possible explanation.  Now that physicists have described ways in which a universe could have arisen out of nothing by purely natural processes, why does it matter whether physicists can prove that this is how it actually happened?  Since you previously said God must exist because there was no other possible way it could have happened, isn't it a sufficient refutation of your "proof" that there is, in fact, at least one possible way after all?

  • As a Christian, what does it matter that some percentage (that you completely made up) of humanity throughout history has had some sort of spiritual experience that lead them to believe in some sort of god or gods?  Even if that somehow proved that there was some sort of God (which it doesn't, since it would only prove at most that humans have a tendency to believe in supernatural beings), what justification is there for assuming that the "God" in question is the Christian one and not, say, the God of Islam, Zoroastrianism, Norse mythology, etc.?

  • How can you claim that the Bible is evidence of the existence of God and then admit that much of it is allegorical and not to be taken literally?  Especially when, once upon a time, it was all thought to be literally true until science and evolving societal norms slowly but surely proved that more and more of it couldn't possibly be literally true??  Also, how do you determine which parts are literally true and which parts are merely allegorical??  Does it bother you that the determination of which parts are literal and which parts are allegorical has changed over time, indicating that there is no "correct" answer other than "everything is literally true that hasn't yet been shown to be demonstrably false or distasteful to our modern sensibilities"?

  • On a related note, how can you claim that "absolute morality" can only come from God and then acknowledge that the only source we have for what God's morality actually is (i.e., the Bible) contains numerous laws and principles that do not apply to today's society and therefore are not absolute?

  • You claim that God is necessary in order to explain what the purpose of life is, which is something science cannot do.  What justification do you have for the assertion that life must necessarily have a purpose in the first place, other than the fact that you find the notion of a life without a purpose to be too depressing to contemplate?

  • Once you have "logically proven" the necessity of some sort of timeless and immaterial supernatural being in order to explain the creation of the universe and all its laws (leaving aside for the moment the question as to whether you actually did prove anything), how do you get from that supernatural being to the God of your particular religion and your particular sect of your particular religion? If you're trying to prove something, it's not enough to just say you have faith in your God or that your God personally spoke to your heart. You're perfectly entitled to your faith, but that's not the "proof" you promised to provide.

Friday, May 1, 2015

Every Theist vs Atheist Debate In a Nutshell

All right, so maybe the title of this post is a wee bit broad, but after watching (and engaging in) many debates between "Theists and Atheists" (a.k.a "Creationists vs Scientists", "Christian Apologists vs. Agnostics" or what have you), I've finally realized that every single debate always ends up following the exact same pattern.

From the atheist side comes the following points, stated in a wide variety of forms:
  • There is no empirical, verifiable, reproducible evidence for any sort of God that is actually worshiped by any religion on earth (leaving open the question whether some sort of timeless, immaterial, non-interventionist, supernatural being might possibly exist beyond our ability to perceive it in any way).
  • The various holy scriptures used by different religious beliefs to justify their faith are all deeply flawed insofar as they have descriptions that are at odds with reality (either readily observed or experimentally verified).  These include descriptions of the creation of the world, supposed miracles, historical events, prophecies, etc.
  • Therefore, since there is no good evidence to support the existence of God and what little evidence is offered is flawed, there is no good reason to believe in God.

From the theist side comes the following points  (again, stated in a wide variety of forms):
  • The holy scriptures state that the entire universe was created by God and therefore "God did it" is an all-encompassing explanation for everything in the universe.
  • Atheists (or scientists) cannot completely explain every single observed phenomena in the universe and provide exact description of every single historical event or process that led the universe to be the way it is today.  And for things that do have a scientific explanation, atheists (or scientists) cannot prove those explanations to be 100% true and accurate in every single case.
  • Therefore, since atheists can't explain everything perfectly and theists have a book that lets them use "God did it" as an explanation to explain everything, there's no valid reason to not believe in God.

In other words, theists and atheists are basically having two completely different conversations, and debates between theists and atheists are therefore usually "won" or lost" based entirely on how the debate is framed.  If the debate is framed by theists as "who can claim to have a source of All Truth," then the theists are going to win every time since atheists aren't actually making any claims to knowledge.  If, however, the debate can be framed as "is there any good evidence to support a belief in God or isn't there," then the atheists have a shot.

The problem comes, however, when theists almost always shift the debate away from their own burden of proof and atheists let themselves be put on the defensive as they try to prove how science has better methods of explaining the universe.  Atheists, however, don't actually need to provide an alternative explanation for everything theists claim can be explained by God, and they should really stop letting themselves get drawn into that sort of discussion during a debate.  Sure, it's awfully nice that modern science has well-tested and verified explanations for such things like how stars and planets form, how life evolves, etc., but that really has nothing to do with whether or not God exists.  Even if science had no explanations whatsoever to explain anything about the world around us, that would simply prove that "we don't know" and not that "God did it."  If a theist wants to prove that "God did it," it's not enough to simply point out that atheists don't have a better explanation -- they need to offer compelling evidence that God did, in fact, do it.

Once the debate is shifted away from "atheists can't prove that God didn't do it", it's possible to actually examine and refute any evidence offered by theists to prove that God exists.  If they go with the argument from design, point out the flaws in that argument.  If they claim their holy book is inerrant, point out all the things that it gets wrong.  If they claim that God is required to have absolute morality, point out that the Bible is full of moral laws that no longer apply today and that every single religion interprets God's laws in a different way (not to mention the fact that many atheists perform good deeds while many theists perform atrocious acts, often justified by their belief in God).  If they go with a cosmological argument that requires some sort of "creator,"point out how much of that argument depends on creative use of definitions (if you can), point out the inconsistency in claiming that everything except for God requires a creator (if you can make a special case for God, why not a special case for the Universe?), and point out that "proving" the existence of a timeless, immaterial being who -- by definition -- cannot possibly interact with the material world or be detected in any way doesn't really provide evidence of any sort of God actually worshiped by anybody.  If they resort to personal anecdotes ("I felt Jesus come into my heart") or so-called "Faith Promoting Stories" ("Little Bobby was lost in the woods and prayed, and then he was rescued!"), point out that anecdotes are not the same as evidence and that confirmation bias let's them ignore all the times Jesus didn't come  into someone's heart and heartfelt prayers weren't granted.  Finally, if they claim that a belief in God gives them comfort, acknowledge that being comforted by a belief isn't actually evidence for the truth of what is believed.


Shifting how a debate is framed isn't always easy, especially when theists know that the only way to succeed is to avoid having to actually justify their own position.  No matter how many times you try to point out that they have no good evidence for what they believe, they will constantly try to get you to provide 100% perfect explanations for everything.  And even if you do manage to shift the debate to actually discussing the evidence for God, it can be an uphill battle wading through the mountains of misinformation and, sad to say, outright lies that get offered as evidence that everything in the Bible is literally true or that religious miracles really did occur, etc.  If you know your stuff, however, and keep the debate focused on the actual topic, you might just get theists to admit that they don't actually have any good evidence for their beliefs and are relying primarily on faith instead.   And that's pretty much as far as you can hope to go, in my experience.  After that it's up to the theists (and those those in the audience watching the debate) to decide whether faith is enough to justify the way they choose to live.

Friday, April 24, 2015

Top Ten Misconceptions about Atheists - Part Four

Misconception Number Four -- Atheists Cannot Act Morally

OK, I discussed morality in some depth earlier in this post, but it bears repeating here the common misconception that a belief in God is required for somebody to act in a moral way and that, therefore, atheists cannot be moral.

Rather than rehash the entire discussion here, let me just make a few bullet points that explain why this misconception is, well, a misconception:
  • There are entire societies that lack a belief in God, such as communist China, that are full of people being nice to one another and treating each other in a way that is, by all accounts, very moral.

  • Morality existed long before the Bible was written.  Even if you accept the Bible as a literally and exclusively true account of human history, does anybody really think that people thought it was perfectly OK to murder, steal, lie, etc., before Moses was given the Ten Commandments?  Did people really need to be told, "God says that murder is wrong" before they were able to figure that out on their own?  Seriously?

  • If "absolute morality" comes from God and is the only way to avoid any sort of "relative morality" (i.e., where different cultures think different things are moral and immoral), then why are there so many religions who interpret the same moral laws in different ways?  Why do some Christians believe homosexuality is a sin, while others think it's perfectly fine?  Why do some Christians feel that divorce is a sin, while others think it is perfectly fine?  Having a source of "absolute morality" doesn't seem to mean all that much as long as nobody can actually agree what that source actually says.

  • On a related note, if God is supposed to provide "absolute morality" that is required for us to behave in a moral way, why have those moral precepts changed over time?  Why did it used to be a sin to eat pork and eat shellfish and wear fabric made of two kinds of cloths, but now it's not a sin?  Why it used to not be a sin to own slaves, but now it is a sin?  The standard answer seems to be that Old Testament laws (some of them, at least) were given to a particular people living in particular circumstances and no longer apply to our circumstances today.  Except, isn't that the very definition of "relative morality"?  And isn't it awfully convenient that the laws that "no longer apply" today just happen to be the ones that we don't actually want to follow today?

  • Most importantly, who decided that any sort of "absolute morality" is even needed in the first place in order to be moral?  Morality is just a word, a human construct, that defines how people think we should act toward one another.  It varies from time to time, from place to place and from group to group.  At it's most basic, morality is simply a feeling that we should treat other people the way we want to be treated.  Or, more simply, don't be a dick toward others.  It's rooted in our evolution as intelligent, empathetic creatures and likely evolved as a way to help humans live together in a society instead of having to go it all on our own.  As a result, concepts of morality can and do evolve over time as societies evolve and there's no need to point to any sort of "absolute" morality in order to whether an act is moral or not within a particular society.   We may think France is "immoral" because they let women walk around topless at beaches.  Arab countries feel the United States is "immoral" because we let women walk around with their hair and faces exposed.  And each culture is convinced that their beliefs are guided by "absolute" moral principles handed down from on high.

  • In short, you don't need to believe in God to think you should treat other people with respect, and a belief in God certainly doesn't lead all believers to treat others with respect.  In fact, you could argue that humans are inherently moral creatures and it takes a belief in God (or religion, if you prefer) to convince people to treat other people as "lesser beings" for not sharing those beliefs.
All right, my "few" bullet points ended up being more than just a few.  Just think of this post as strengthening my previous post on the subject rather than rehashing it.

Monday, April 20, 2015

Another Evolution Analogy

In a previous post I discussed (among other things) Richard Dawkins' "Climbing Mount Improbable," in which he laid out a good analogy comparing the gradual process of evolution to a walk up a very gradual slope that eventually leads to the top of a very high mountain.  It's a very good analogy, but I fear it may require a bit too much work to accept it since (a) not everybody has experience with climbing up gradual slopes and (b) a change in altitude is not really in the same conceptual ballpark as the change that species undergo over time.  It's strength is, I believe, primarily in the way it conveys how extremely small changes can add up to large changes over extreme lengths of time.  But some folks will probably still reject it because they simply can't get their minds wrapped around the comparison of time to distance.

After much thought, I believe I have come up with, if not a better analogy, at least a complimentary analogy to the one Professor Dawkins discussed.  It lacks the sense of vast time in Dawkins' analogy, but is more grounded in everyday experience and deals with actual biological processes.  It also helps deal with the common objection heard by Creationists that there are no "transitional" fossils that show one species evolving into a completely different species.

Let's imagine a father who photographs his newborn child and decides to take a new photograph of the child once every minute of every hour of every single day from that point on. At the end of the first day, the father has 1400 pictures, after one week he has 10,080 pictures, and at the end of a year he has a whopping 525,960 pictures. At the end of ten years, the stack has grown to 5,259,600 pictures, and by the time the child is 50 years old, the stack has grown to 26,298,000 pictures. And (assuming the father was extremely long-lived or passed the duties on to somebody else), by the time the child is 90 years old, the stack has a massive 47,336,400 pictures, all showing the gradual growth of a baby into an elderly man one minute at a time.


Now, over a period of ninety years, the child has changed from a newborn infant to an elderly man, and along the way the child progressed through various well-defined stages (infant, toddler, child, pre-teen, adolescent, young adult, adult, middle-age, senior citizen, elderly) . And if you randomly selected any example from that stack of 47,336,400 pictures, you would be able to clearly identify which stage of life the child was in at the time that photograph was taken. No photograph, however, would show a clear "transition" from one stage to the next. You wouldn't, for example, find a picture showing the child with the body of a baby and the head of a toddler. Or the arms of a teenager but the legs of an adult. Or (to mirror some of the extreme examples asked for by Young Earth Creationists), the body of an infant and the head of a senior citizen.

The point is that the change from infant to elder is so gradual that there are no clear-cut transitions from one stage of life to the next. Somebody may legally be considered an adult at the age of 18, but it would be impossible to detect any physiological differences between a person one minute or one hour or even day before his 18th birthday and one minute, hour or day after his 18th birthday. And this isn't to say that there aren't any transitional photographs of the child; instead, it means that every single photograph shows a transition from the previous minute to the next minute and the supposedly "well-defined" stages of life are really just shortcuts we use to describe people instead of actually having some sort of absolute definitions.


The same is generally true with regard to the fossil record and the evidence it provides for evolutionary processes.  Just as children gradually change into adults over time, species gradually change into other species over time.  The only difference is that species change over millions of years instead of 90 years, but the principal is the same.  Just as you will never find a photograph of somebody who has the head of an infant and the body of an adult, you will never find a fossil showing the head of one species and the body of a previous species.  And this isn't to say that there aren't any transitional fossils; instead, it means that every single fossil shows a transition from the prior generation to the following generation and the concept of "well-defined" species is really just a shortcut we use to describe life instead of actually having some sort of absolute definition.

Friday, April 3, 2015

Religious Freedom to Discriminate?


There has been a lot of discussion in the news lately about various state and federal laws that purport to "restore" religious liberty but which, in reality, are specifically designed to allow people and businesses to discriminate against other people based on their religious beliefs.    Despite the broad language of the laws, the legislative history shows that they were specifically implemented to prevent people and businesses from being "forced" to provide services to gay couples looking to get married.  So, for example, a cake shop couldn't, under these laws, be sued civilly for refusing to make a cake for a gay wedding and a photographer couldn't be sued for refusing to take wedding pictures for a gay couple.  Because, you see, in many states the existing laws prohibited businesses from refusing to provide services on the basis of race, religion, ethnic origin, gender or sexual preference, so these new laws provide a loophole if the discrimination is based on one's religious beliefs (as opposed to garden-variety bigotry, I suppose).

The language used to draft and support these laws is positively Orwellian, of course, as they try to argue that it's not at all about discrimination and solely about religious freedom, despite the fact that the freedom being sought is, in fact, the freedom to discriminate against others.

All of this has been said before by many other people.  One key thing seems to get ignored during discussions of these laws, however.  Since when does Christianity (or any other religion, for that matter) actually teach that it's OK to discriminate against anybody in the first place?  I mean, if the government passed a law saying that, for examples, Mormon churches had to perform temple marriage ceremonies for gay couples, or Catholic churches had to start ordaining women to the priesthood, I would agree 100% that this was an unconstitutional intrusion of the government into religion.  And that's because a core Mormon belief is that temple marriages are reserved for the joining of a man and a woman, and a core Catholic belief is that only men can hold the priesthood.  You may disagree with those beliefs, but they are certainly things actually taught by those religions and accepted by the members.

However, while the Mormon church does teach that gay couples are not "worthy" of being married in the temple, I don't recall any teaching saying faithful members are not allowed to provide services to gay couples who are getting married elsewhere.  Similarly, while the Catholic church does not allow female priests, I'm pretty sure there's no prohibition against providing services to a woman who happens to be a clergy member of another religion.  Heck -- the Catholic church prohibits divorce and I doubt you'd find a single catholic photographer or baker who refused to provide services at a wedding that involved a divorcee remarrying.

The point is that Christianity teaches that you should not sin, true, but it does not teach that you should discriminate against those who believe differently than you.  So, while your "religious freedom" certainly includes the right to practice your religion the way you see fit, it doesn't give you the right to discriminate against those who don't share your beliefs.  And, while you may claim that discrimination against others is how you practice your religion, you're just using your religion as a shield for your own bigotry since that's not what your religion actually teaches.

[As an aside, I can't help wondering why nobody claims to be unable to provide services to people who, say, violate the sabbath by holding their wedding on a Sunday, or who have committed adultery, or who worship some other God, or who have shown disrespect to their parents, etc.  These are all sins specifically prohibited by the Ten Commandments, which is supposed to be the most important thing in the entire Bible.  Maybe it's because the people who want to discriminate against gays commit all those other sins themselves?  Or maybe it really is just the fact that they are prejudiced against gays and are looking for a justification for their prejudice.]