Evolution and Why Labels Don’t Matter

Theists (especially Young Earth Creationists who deny the reality of evolution) love to make a big deal about the emergence of species, constantly asking for evidence of one species (or “kind”) turning into another, or asking how the “first” member of a species could have possibly shown up suddenly one day if it had no other member of its species to mate with, etc. Here’s the thing that these folks either do not understand or else choose to ignore, however:

We humans looooove labels. We just can’t help ourselves. We have this innate burning need to distinguish everything from everything else and give it all labels to make sure that everybody knows what we are talking about. We have chairs and we have beds. When somebody invents something that can be used as both a chair and a bed, we call it a futon rather than just admitting that “chair” and “bed” are arbitrary labels in the first place. We label eating utensils that have tines as “forks” and eating utensils that have bowl-like depressions as “spoons”. But then somebody comes up with a utensil that has tines and a bowl-like depression, and we have to come up with a new label “spork” (or “runcible spoon,” if you prefer) because we just can’t deal with something that contradicts our previously defined labels.

The same is true with biology. We have “cats” and we have “dogs” and we have “birds” and we somehow think that just because we have come up with these labels that nature somehow cares one whit about making sure that reality conforms with them. And, sure, it’s pretty obvious that cats and dogs and birds are pretty distinct from each other, but things get awfully muddy when you start labeling each individual species of cat, dog and bird. Not to mention ape. We have arbitrarily defined “species” as groups of animals that can interbreed with each other, but this is simply our way of labeling things and not a hard and fast natural law. That’s why there are things like “ring species” where one group of animals can interbreed with a similar group living in proximity to them, and that group can interbreed with another group that lives in proximity to them, etc., but you eventually get to a group that can interbreed with their closest neighbor but can not interbreed with the original group. We then feel compelled to label the last group a different species from the first group.

All of this is to say that, yes, evolution is true and occurring all the time and yes, this means that any labels we put on things with regard to species, genus, etc., are necessarily going to be imprecise and have gray areas and be subject to revision. Which is, of course, why it is so ironic when some people who deny evolution claim it’s impossible for one “kind” of animal to evolve into another “kind” over time, as if they themselves have some infallible way of labeling things.

Why the Word “Supernatural” Is Meaningless

[Periodically, a question comes up asking whether atheists reject the entire idea of “the supernatural” all together or whether it’s just God that we don’t believe in. I can’t speak for all atheists, but as far as I am concerned the entire idea of “supernatural” is a wholly empty and meaningless concept to begin with. Of course, every time this question is asked, I come up with a slightly different way to express my feelings, so this post just captures my various responses.]

The word “supernatural” is wholly meaningless because:

1. The natural world encompasses everything we can see, feel, hear, taste, measure or in any way detect.
   
2. In order for something to truly be “supernatural”, it would necessarily need to not be part of the natural world.
   
3. Anything that is not part of the natural world cannot be seen, felt, heard, tasted, measured or in any way detected.
   
4. Therefore, regardless of whether anything supernatural exists or not, it is meaningless to talk about it since there is no way to detect it or know anything about it. The moment it becomes detectable in any way, it ceases to become supernatural. 

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In my experience, “Supernatural” is just a term that people use to describe proposed things for which there is no proof or good evidence but which we nevertheless think might possibly exist in some sense. Or, perhaps, things that we really wish existed despite all evidence to the contrary. For example:

• We have no real proof or good evidence that God exists, but we really, really wish He did, so let’s say that God is “supernatural” to explain why we can’t detect any evidence of His existence rather than acknowledging He doesn’t actually exist.
  
• We have no real proof or good evidence that ghosts exists, but we really, really wish they did, so let’s say that ghosts are “supernatural” to explain why we can’t detect any evidence of their existence rather than acknowledging they don’t actually exist.
  
• We have no real proof or good evidence that psychic powers exists, but we really, really wish they did, so let’s say that psychic powers are “supernatural” to explain why we can’t detect any evidence of their existence rather than acknowledging they don’t actually exist.
  
• We have no real proof or good evidence that the human spirit or soul exists apart from human brains, but we really, really wish they did, so let’s say spirits and souls are “supernatural” to explain why we can’t detect any evidence of their existence rather than acknowledging they don’t actually exist.

Rinse and repeat.

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Atheists, as a rule, don’t claim to have beliefs or knowledge about ultimate or absolute truths. That’s usually the realm of theists, and atheists generally say they don’t believe those claims.

As a rationalist, however, I strongly believe that “supernatural” is just a term made up to justify a belief in something for which there is no supporting evidence. Sure, there are things in the world that people can’t currently explain. Perhaps there even things that we will never be able to explain (why does seeing a person yawn make us want to yawn as well?). But anything that we can observe or detect or that has any effect whatsoever on the natural world is, as far as I’m concerned, part of the natural world and therefore, by definition, not supernatural.

Or, to put it another way, the supernatural cannot exist because existence itself is a natural state:

1. Something can be said to exist if it is composed of matter or energy and occupies time and space.
   
2. Anything that is composed of matter or energy and occupies time and space is part of the natural world.
   
3. Anything “supernatural” would, by definition, not be part of the natural world and would therefore need to not be composed of matter or energy nor occupy time or space.
   
4. Therefore, anything supernatural cannot be said to actually exist. Q.E.D.

A Revelation Regarding Arguments for the Existence of God

OK, so the title of this post is intentionally meant to be humorous, but after watching yet another debate between a theist and an atheist regarding the existence of God, I had a sudden realization.  An epiphany, if you will.

The theist side of most of these debates usually consists of three main angles of attack:

1. God's existence can be logically proved via a number of different arguments, such as the Cosmological Argument, the Argument from Design or the Argument from Contingency (which is really just a subset of the Cosmological Argument).
    
2. Science (usually equated with atheism for some reason) can't explain everything (or anything, with 100% certainty), but the "God" hypothesis can, so therefore it is more reasonable to believe that God exists.
   
3. Faith, personal revelation, etc., "prove" that the theist's accepted version of God is the right one (which is why Muslims use the same exact arguments as Christians to "prove" wildly different versions of God).

Now, the third angle of attack can usually be dismissed out of hand, simply because the theist acknowledges that there is no way to prove the assertion and it's really just a statement of belief (no matter how deeply held).  And the second line of attack is also pretty easily dismissed, since it's trivial to explain that the burden of proof lies on the head of he who is making a positive claim ("God exists") and atheists don't have to be able to explain anything (or everything) with 100% certainty if theists can't even prove that God exists in the first place.

And so, most of these debates tend to revolve around the first angle of attack.  The theist runs through the same tired arguments that have been refuted time and time again, and the atheist goes through the motions of pointing out how they have been refuted time and time again.  And nothing ever gets resolved!  Even if the atheist refutes every single point made by the theist, even if he explains in careful detail the unwarranted assumptions, begged questions, leaps of logic and major fallacies employed while making the arguments, the theist just continues blithely on to the second and third angles of attack as if nothing happened.

And this is when I had my revelation.  Theists who make these arguments purporting to prove the existence of God aren't actually trying to convince atheists that God exists.  Instead, they are simply trying to offer logical-sounding justifications for what they believe so as to not appear illogical, foolish, gullible, stupid, idiotic, or what have you.  They know that their belief in God is based on a wholly irrational foundation of faith (not to mention cultural inertia, family experience, etc.), and they trot out these arguments to make themselves feel better.

Again, this becomes extremely apparent after a theist runs through all the "logical" arguments as to why a God (of some sort) must necessarily exist, but then has to resort to an appeal to faith or personal revelation or an appeal to emotion to bridge the gap between the supposedly proven "first cause" God and the God that they personally believe in and worship.

All of which is to say that debating theists over the existence of God is probably a useless exercise.  People don't tend to believe in God for logical reasons in the first place, so refuting the logic of their proposed arguments isn't likely to change their opinions.  The arguments are nothing but smokescreens to hide the fact that their beliefs are not based on logic or evidence, since appeals to faith typically don't carry too much weight with the faithless.

The "Theory" of Evolution

I've lost count of how many times I've heard or seen fundamentalist theists (whether Christian or Muslim) disparage the entire concept of evolution by saying, "it's just a theory."  As in, "Scientists claim that man evolved from apes, but the Theory of Evolution is just that -- a theory!  It's nothing more than a guess!"  I've also lost count of how many times I have heard or seen people (whether atheists or just rational theists) respond to this claim, but the responses always seem to be one of two different approaches.  Some people go with a glib response to the tune of, "Evolution is 'just' a theory the same way gravity is 'just' a theory!"  Others point out that the word "theory" has a different meaning when used in a scientific context than it does when used colloquially.  In other words, while theory can certainly mean "simply a guess or conjecture" when used colloquially, when scientists use the term they mean "a coherent group of tested general propositions, commonly regarded as correct, that can be used as principles of explanation and prediction for a class of phenomena."

Neither of these two standard responses are particularly helpful, in my opinion.  The first suffers simply because it is glib, and doesn't really offer enough information to change anybody's mind on the subject.  Glib responses, in my experience, are best suited to making the person making the response feel superior, but don't typically have much affect on the respondent.  The second response, while informative and accurate, suffers because it completely misses the entire point.  It doesn't really matter if "theory" is defined to mean that it's not "just" a guess but is instead supported by evidence and generally accepted as true.  That still lets fundamentalists claim that it doesn't have to be true.  "After all," they might argue, "for centuries it was generally accepted by scientists that the earth was flat, or that the sun revolved around the earth, or that everything was made up of earth, air, fire and water."

No, I think the best response to the whole "it's just a theory" argument is to point out what the Theory of Evolution actually is, not what the word "theory" means.  And no, I don't mean explain all the details of the theory and point out all the evidence that supports it (although that can certainly be helpful if you have the scientific background to pull it off).  I'm talking about something a lot more basic which always seems to get missed in these discussions.  It is important to explain that the Theory of Evolution is not the proposition that there is such a thing as evolution in the first place, that all currently existing species (including man) have evolved from previously existing species, and that all life on earth shares a common ancestor who lived billions of years ago.  Instead, the Theory of Evolution is the proposition to explain how and why all of that took place.

Evolution, in other words, is an observable, demonstrable fact and not a theory at all!  The Theory of Evolution is our best explanation (supported by evidence and commonly accepted as accurate) as to what caused (and still causes) that fact.  And just because our best explanation might be incomplete or inaccurate or just flat-out wrong doesn't say anything about whether scientists are at all unsure as to whether evolution is a real thing.  This is similar to how the "Theory of Gravity" does not seek to explain whether or not there is gravity, but instead seeks to explain why there is gravity and how it works.

Evolution is an observable and demonstrable fact, plain and simple.  We have a multitude of evidence from various sources, such as the fossil record, comparative anatomy, DNA analysis, etc., that shows unequivocally that all life on earth has evolved from prior life forms over time and that all living creatures shared common ancestors in the past.  Evolution itself is not a theory -- it's simply an observation.  The Theory or Evolution deals with how and why evolution occurred, and the commonly accepted explanation is that evolution is caused by the occurrence of random mutations within a population that gives rise to variety, and that changes in environment cause different variations within the population to either thrive or perish, which over vast time scales can lead to entirely new species, genera, orders, classes, phyla and even kingdoms.

Whether this theory is wholly accurate and complete can certainly be discussed.  It is, after all, "just" a coherent group of tested general propositions, commonly regarded as correct, that can be used as principles of explanation and prediction.  Maybe there are additional factors at work that we haven't figured out yet.  Maybe some of the factors we currently believe to be involved aren't as important as we think.  Maybe we've got it completely wrong and there is a totally different explanation for how evolution has occurred (and is still occurring).  Maybe that explanation is even "God did it" (or "aliens did it" or "magic pixies did it").  But none of that uncertainty changes the fact that evolution has occurred and continues to occur.

Evolution is a fact.  The explanation as to how it works is a theory.  A very good, commonly accepted theory that can be and has been used as principles of explanation and prediction, but a theory nonetheless.  And this, I believe, is the best response to the whole "evolution is just a theory" argument.  No, the "Theory of Evolution" is a theory, but evolution itself is an an accepted, observable, demonstrable fact.

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.

Something from Nothing?

Many modern Christian apologists delight in attacking atheists for their supposed belief that the universe was created “out of nothing,” presumably in reference to the Big Bang theory of the origin of the universe. I’ve always felt this was a very off means of attack, however, for the following reasons:

1. First of all, Christian theology itself has long taught that God created the entire universe ex nihilo (literally, “out of nothing”). So, apparently, creating something out of nothing is only a ridiculous idea if God didn’t do it. That’s very helpful if you are then going to define God as basically “that being who is the only being who can create something out of nothing.” You can then argue that (a) the universe was created out of nothing, (b) only something we will arbitrarily call “God” can create something out of nothing because we say so, therefore (c) “God” exists.
2. Second, this whole line of attack completely misrepresents what science actually says about the origin of the universe. The so-called “Big Bang” theory does not actually state that the universe was created “out of nothing.” Instead, it claims that the entirety of the universe was once condensed into an infinitesimally small point billions of years ago and that it expanded from that point. There are various competing theories as to how the universe came to be condensed into a tiny point in the first place and what caused it to expand (including the theory of a cyclic universe that constantly expands and then contracts over and over again, the theory that our universe branched off of another existing universe, etc.), but none of these theories claim that the universe suddenly appeared out of nowhere. Which is to say that there is nothing whatsoever in the current scientific understanding of the origin of the universe that requires the existence of some sort of “being” who can create things out of nothing.
3. For centuries, even thousands of years, Christians have believed that the Earth and entire universe was created sometime in the last 10,000 years. Many modern “intellectual” or “sophisticated” Christians today acknowledge the scientific evidence and discoveries that show the Earth is actually around 4 billion years old and that the universe far older than that, although there are still plenty of fundamentalist Christians who think the whole universe was created some 6,000 years ago. What I find hilarious is that these modern Christian apologists are willing to chuck out the literal words of the Bible and accept what science has to say about the age and origin of the universe, but then want to take what science says and somehow use it to support what the Bible says about God creating the universe. Creating the universe in six days? Well, that just an allegory. But the bit about God doing it? That’s literally true!

Accepting Evolution

Although the theory of evolution doesn't really have anything to do with Atheism, per se,  it often comes up in discussions with theists who apparently feel threatened by something which can so fully explain observable phenomena that theists have been claiming for centuries could only be explained by the existence of a divine creator.  Before the theory of evolution was proposed (and, eventually, accepted), there just wasn't any good way to explain the immense diversity of life on earth and the way it is all so interconnected.  Of course, claiming that God "must" have done it since we can't think of any other explanation is a classic argument from ignorance, but the fact remained that there were no other decent explanations for a long time.  With the theory of evolution, however, you no longer need God to explain everything, and this has led some theists to attempt to undermine its acceptance at every opportunity.  Not all theist, mind you -- the Catholic Church, for example, officially recognizes the science behind the theory of evolution and "merely" claims that God directed the process and at some point in that process injected the human soul into the mix.

Somebody once me asked whether it was possible to come up with grand unifying analogy or quote to fully explain the theory of evolution and make it more understandable and accepted by whose who deny it. Unfortunately, while analogies may be useful in understanding the general concepts underlying evolution, I don't think they are much use when it comes to actually accepting the truth of evolution. And this is the case with most fields of science that attempt to explain things that are not, and cannot, be perceived directly and which may even appear to contradict our everyday experiences.

Relativity is truly weird, especially when you talk about curved space/time. Sure, comparing space/time to a rubber sheet and massive objects to a bowling ball rolling along that sheet may help me understand the general idea that somebody is talking about, but at the end of the day it doesn't really help me to understand what space/time really is or accept that it can be somehow distorted by massive objects. That will only come by learning a lot of complex mathematics and performing (or at least studying) tons of experiments.  And if I insisted that all theories that describe reality must comport with my "common sense" view of the world, I would never be able to accept the validity of relativity, despite the fact that it is widely accepted among physicists and is actually used on a daily basis for such things as making adjustments to GPS satellites that are further away from the Earth's gravitational pull and therefore run at a slightly different speed than clocks on earth.  Seriously weird stuff, but also seriously true.

Quantum mechanics is even worse. It has been said that nobody truly understands it, and yet its principals have been borne out by experimentation and physicists can make accurate predictions based on the various laws that have been discovered regarding it.  Of course, the world we can observe with our eyes and ears does not operate on the quantum level, and once again my "common sense" experiences are not a reliable means of judging the validity of quantum mechanics.

Like relativity and quantum mechanics, the theory of evolution describes reality as it occurs on a scale not generally observable by our standard senses.  In the case of evolution, the scale has to do with time rather than size or speed or distance.  And, just like relativity and quantum mechanics, we cannot rely on our own "common sense" experiences as a guide to determining whether or not it is an accurate description of reality.  Once again, however, just like the theories of relativity and quantum mechanics, the theory of evolution provides an explanation as to why the universe behaves the way it does and also lets us make falsifiable predictions as to what will happen in the future.

[As a side note here, let me point out that the word "theory," when used in a scientific sense (like the theory of gravity or the theory of relativity), does not mean an unverified guess or idea.  In scientific terms, that would be a "hypothesis".  Instead, the word "theory" is used to describe a system of interrelated laws and principles that have been tested, validated and confirmed and that are used to describe a particular area of  observed reality.  In other words, you don't get to call something a "theory" in science unless it has been proven to be be true.]

To understand evolution, all you really need to know (and I hope I'm getting this right) is that (a) small, random changes are occurring all the time within all biological organisms due to such things as random cosmic ray bombardment, (b) the environment in which most organisms live is constantly changing as well (either due to a change in the environment itself or because the organisms have moved to a different environment), and (c) these two factors frequently combine so that some members of any given species find themselves better suited to the current environment (and thereby survive to pass on their genes to future generations) while other members of that species find themselves less suited (and thereby do not survive to pass on their genes to future generations). Add to that a time span of billions of years for small changes to accumulate, et voila!

The best analogy I have read to help me accept the truth of the theory evolution is the one described in Dawkin's "Climbing Mount Improbable." It doesn't lend itself to a pithy quote, unfortunately, but the general analogy compares the evolution of, say, mammals from their ancient fish-like ancestors to a sheer-faced cliff hundreds (thousands?) of feet high. To somebody standing at the base of the cliff, the very thought of leaping to the top in a single bound is impossible to consider, just like it may be impossible to imagine a fish turning into a mouse. But, the analogy continues, what if you could look at the other side of the cliff and see a gradual slope extending for tens (or even hundreds) of miles in the distance, leading from sea level all the way to the cliff's edge? If you started a journey from the very beginning of the slope, the incline would be so gradual that at no point in your journey would you ever even notice you were rising. You could travel for days, weeks, months and still appear to be traveling on perfectly level ground. And yet, at the end of your journey you would eventually find yourself thousands of feet in the air despite never having made any perceptible leaps whatsoever.  Replace "hundreds of miles" in the cliff analogy with "billions of years" in the theory of evolution, and the analogy is complete. The analogy only works, however, if you fully understand the processes involved with evolution in the first place.

Hopefully, this analogy  provides with a framework to understand how evolution is even possible, similar to how the bowling ball on a rubber sheet analogy might help somebody understand the concept of warped space.  It's not an exact analogy, but it should help (assuming, of course, that somebody actually wants to understand how evolution could possibly be true instead of just rejecting it out of hand).  Having said that, let me just address a few of the most common criticisms I have seen and heard lobbed at evolution by those who clearly do not understand how it could be possible:

• If humans evolved from apes, why are there still apes around today?  This is an easy one to answer -- humans did not evolve from apes!  At least, not from the apes that are around today.  Instead, humans and apes both evolved from a common ancestor species millions of years ago and we turned out different from modern apes because we moved to different locations than they did, encountered different challenges than they did, faced different environments over time, etc. It's sort of like asking, "If the English language evolved from Germanic roots, why are there still German speaking people today?"
  
  
• If evolution is true, why don't we ever find any "transitional" fossils that are clearly in between two other species?  The answer to this is that scientists have actually found many different transitional fossils, especially in recent years.  Numerous fossils have been found in the fossil record that show some characteristics of fossils found earlier in the fossil record and some characteristics of fossils found later in the fossil record.  The problem is that some people either are not aware of these discoveries (willful ignorance, perhaps) or require impossible standards for "transitional" like a fossil that is half duck and half crocodile, despite the fact that the theory of evolution clearly states that evolution is a gradual process with no sudden leaps from one species to a wholly unrelated species on in a single generation.  No duck ever gave birth to an animal that wasn't a duck, but over millions of years what is a duck now may be quite different from what was a duck back then.
  
  
• If evolution is true, that means we are just animals and therefore have no reason to act morally toward one another.  Well, aside from the fact that this is basically arguing from the consequences (a logical fallacy where you try to disprove something simply by pointing out the possible negative consequences of that thing), I would have to take exception at the "just" part of this criticism.  True, evolution means that humans are animals, but why do we have to be "just" animals?  A dolphin is not "just" an animal -- it is an animal with a highly specialized, perhaps unique, ability to navigate underwater using sound.  An eagle is not "just" an animal -- it's an animal with exceedingly keen vision and the ability to soar through the sky.  And man is not "just" an animal, either -- he (or she) is an animal with a highly developed intelligence and moral sense that has evolved over time to help us better survive in our environment.  The fact that we are animals doesn't mean we can't be different from other animals in significant ways, and it certainly doesn't mean that we have to act like other animals any more than you would expect an eagle to act like a dolphin (or to act like a penguin, for that matter).
  
  
• Evolution is just a "theory" that Darwin made up and scientists have blindly put their faith in it ever since!  Actually, no.  As mentioned above, the scientific use of the word "theory" (as in the "theory of gravity" and the "theory of relativity") used to describe a system of interrelated laws and principles that have been tested, validated and confirmed and that are used to describe a particular area of  observed reality.  Darwin (and others like him) may have first proposed the idea of evolution, but it didn't become a scientific "theory" until it had been thoroughly tested, revised, expanded upon, and confirmed by generations of scientists looking at many different fields for corroboration.
  
  
• The odds of a complex organism like a human arising purely by "chance" are as ridiculous as a tornado whipping through a junkyard and assembling a complete, working jumbo jet airplane purely by chance! You're right, that would be rather ridiculous. But the theory of evolution doesn't actually state that everything happened purely by chance. Yes, it requires chance mutations to occur and accumulate over time, but that's just an ingredient in the recipe and not the recipe itself. The actual process of evolution is driven by the pressure of natural selection. It may be chance when one animal develops more hair than another member of the same species, but it's not chance when that hairier animal survives when the climate gets colder and the less hairier animal doesn't.
  
  
• Evolution can't explain how life got started in the first place.  You are right, it can't.  But, then again, neither can the theory of gravity or the theory of relativity.  And that's because none of those theories actually claim to answer that question and their validity therefore does not rest on whether they can answer it or not.  There is a completely separate field of biology called Abiogenesis that does try to come up with theories to explain how life could first arise (whether from inanimate matter or some other way, such as having been carried to Earth on a comet).  Evolution, on the other hand, starts with the assumption that life exists and then explains how it became so diverse.
  
  
• But, what about [insert anomaly mentioned exclusively on creationist websites that seemingly "disproves" some tangentially related principal]?  I don't have room to mention every single thing that creationists have come up with over the years in an attempt to "disprove" evolution.  The important thing to remember, however, is that not only does evolution stand as the best explanation ever devised for every bit of observed biological phenomena, and not only has it shown again and again that it has strong predictive powers, it is also corroborated by many other branches of science.  If the theory of evolution were just based on the observed fossil record, then maybe attacking the validity of the fossil record could be an attack on the theory itself.  Instead, though, the theory of evolution is based on corroborating observations from the fossil record, from the genetic analysis of living species, from field examinations of species evolving in the wild, etc.
  
  
• But, there's no actual proof of evolution!  Oh, go read a book.  Preferably one written by an actual scientist with a degree from a real university with a degree in a field actually related to the study of evolution.  That is, of course, if you actually want to learn all about the proof instead of just repeating what others have told you. Creationists have been shouting "there's no proof of evolution" for over a hundred years, ignoring or dismissing every single bit of evidence that comes along, as if simply stating that something isn't true will somehow make it not true. Or, in other words, yes there is actual proof of the theory of evolution. Lots of proof. So much proof that it could (and actually does) fill entire libraries. You just have to be willing to look at it.

The Scientific Method vs Theism

As an atheist, I have come to appreciate the scientific method as the best – if not only – way to determine truth. The basic principles of the scientific method are (a) observing a phenomenon, (b) coming up with a hypothesis to explain that phenomenon, (c) performing experiments and/or gathering data to support that hypothesis and (d) refine the hypothesis to fit the experiments and data (or even reject the hypothesis entirely if the experiments and data disprove it). The key point is that the hypothesis needs to match the evidence and not the other way around.

When I was a theist, however, I was taught to start with an acceptance that God existed, the scriptures were true, etc., and then look for evidence to support that belief if necessary. This is superficially similar to the scientific method (and many theists claim that they in fact follow the scientific method), with one key distinction. Whenever data is discovered that fails to support (or even contradicts) the belief in God, the data needs to be tweaked (or sometimes outright ignored). If, for example, geological evidence clearly shows that the Grand Canyon was created via slow processes over millions of years and this data contradicts the notion that the earth is only 6,000 years old, it’s important to selectively ignore the evidence until you can explain the remaining evidence as having been produced by a global flood.

Proponents of “Creation Science” (a.k.a. Intelligent Design”) often point to, say, the perfection of the human eye as proof that it must have been the product of a divine, perfect creator. The eye, the argument goes, is just too complicated and works so well that it couldn’t possibly have happened just by chance. Ignoring for the moment the fact that this is really just an argument from ignorance (“the eye is just too complicated and works so well that I personally can’t understand how it could possibly have happened just by chance”), and also ignoring for the moment that the Theory of Evolution explicitly posits the concept of natural selection as the driving force behind the development of complex structures such as the eye instead of chance, this argument does have the superficial appearance of following the principles of the scientific method. The phenomenon of a complicated, perfectly functioning eye is observed, and the existence of a divine, perfect creator is offered as a theory to explain that phenomena.

Where things go off the rails, however, is when you point out that the eye is not, in fact, perfect. The human eye has a blind spot inherent in its design, which is perfectly explainable when you consider how the eye might have developed over millions of years but doesn’t make much sense for a perfect creator to have done it that way. In addition, human eyes are susceptible to all sorts of abnormalities and diseases, and many people have to resort to corrective lenses or surgery in order to see clearly. In fact, many people are actually born completely blind. Under the scientific method, evidence that contradicts a particular theory causes the theory to be refined or rejected. Under “Creation Science”, however, the response is typically that we live in a fallen state due to the sins of Adam and that is why the eye is currently not perfect (or why people get diseases or why animals feed off each other or why there is so much pain and suffering in all aspects of the natural world, etc.). And this is because, rather than truly following the scientific method to fit the theory to the facts, theists start with a set of assumed “truths” (i.e., that God exists, that He created the universe in a perfect state originally and that we now live in a fallen universe due to the sins of Adam) and then look for any observable facts that support those “truths” while rejecting any that don’t support them.

If perfection of design proves the existence of a perfect creator, imperfection of design can’t somehow also prove the existence of the same perfect creator.  Looking just at the observed phenomena, without any preconceived, unchallenged assumptions as to the existence and nature of God (which is, of course, the very thing that is supposed to be proved so it can't be assumed), imperfection of design is instead evidence of an imperfect creator, or perhaps a malevolent creator, or of no creator whatsoever.  The one thing it absolutely cannot be is evidence of a perfect creator, unless you already believe in the God of the Bible and are simply looking for a justification of that belief instead of actually trying to come up with a theory that best explains the evidence.

People are, of course, free to believe whatever they choose to believe, and the whole reason churches exist is to let people with similar beliefs congregate and share those beliefs with one another. And there’s nothing wrong with that (assuming, of course, those beliefs don’t lead the believers to harm other people as a result). But this essential difference between the scientific method and theism is one of the main reasons why “Creation Science” or “Intelligent Design” has no place whatsoever in a science classroom. Call it what you will, it just isn’t scientific as long as it exists to fit the facts to the theory instead of the other way around.

Man's Place in the Universe

At the core of most theistic beliefs seems to be the assumption that the universe was created for the benefit of man. That may be overstating things a bit with regard to the wide variety of religions in the world, but it’s certainly the case with religions based on the Bible.

Now, it certainly made sense to think this way when the entire known universe consisted of the small amount of land you and/or members of your tribe had personally visited together with a bunch of lights in the sky that appeared to be just out of your reach. And that’s basically where human knowledge stood at the time the Bible was written.

Well, that was then and this is now, as the saying goes. Modern cosmology has shown us just how vast the universe actually is. Not only is the Earth much larger than was imagined back in Old Testament times, we now know we are just one (relatively small) planet in an entire solar system of planets. And our solar system is just one of billions in our galaxy. And our galaxy is just one of billions in the observable universe that extends for billions of light years in every direction. A universe chock full of weird phenomena like black holes and distant quasars and galactic nebulae – most of which mankind was completely unaware of until extremely recently.

I understand that many people take comfort in the thought that God created it all just for us and that he cares about each and every one of us as individuals because we are so special to him. To think that Earth is just a random speck of dust in a vast universe can be a bit depressing. I look at it another way, however. To me, the thought that in the entire vast universe there is only one being exactly like me is awe-inspiring. I am wholly unique, and when I am gone there will never be anything just like me. And the same goes for every single person who has ever lived or who ever will live. It gives my life a purpose to know this, since I have the chance to improve the world in my own unique way and cause ripples that will potentially continue on throughout eternity.

God of the Gaps

As we discover more and more of the laws of nature and are able to explain how everything in the universe came to be in its current state through purely physical means, where does that leave God? God is necessary, according to most religions, to explain what cannot otherwise be explained. He is a supernatural force that becomes the default explanation for anything we don't understand. Once we understand everything, however, what is the rationale for still believing that the universe needed a God? And if God is not a necessary force, then he is nothing more than a figment of our collective consciousness.

Life was a lot simpler back when we didn't understand anything and it was easy to just posit God (or gods) as the explanation for everything. Why did the sun rise each morning? God did it. Why did it rain yesterday? God did it. Why didn't it rain today? God did it. How did we get here? God did it. Why is there so much pain and suffering in the world? God did, er, well let's just change the subject, shall we? We laugh at ancient cultures who invented gods to explain natural phenomena that we fully understand today. And yet, some still cling to the "god" explanation for the few things that we still don't have good explanations for (or things which they personally don't understand).

As our knowledge of the universe has expanded, however, we've pushed the necessity for God as an explanation into a smaller and smaller box, until he's limited to having started the whole thing in motion in the first place but hasn't really done much since then.

Science has done a wonderful job of explaining just about every facet of creation to the point that "God" is no longer a necessary explanation for anything. We're still a bit fuzzy on how it all got started in the first place (although I don't think modern scientists actually think it all suddenly appeared "OUT OF NOTHING"). At most, that leaves open the possibility that some sort of "god" started the whole process going and then left it to run unassisted. Since there's no actual evidence of such a god apart from our lack of understanding, however, there's really no good reason to assume that such a god actually exists. Any more than there was a good reason to assume the existence of Thor simply because we didn't understand how thunder and lightning happened.

Yes, scientific theories come and go (or get refined over time), and some things that we think we can fully explain today may turn out to have a different explanation later on. But (and this is probably the most important point of all) even if every single scientific theory ever advanced to explain the universe was completely and utterly wrong, there still wouldn't be a single bit of good evidence to believe in the God of the Bible (or any of the many, many other gods that have been written about over the past thousands of years). And there are plenty of Muslims who are just as convinced that Allah, as described in the Koran, is the one true God and not the God of the Bible and they make the same exact arguments as Christians do to justify their belief. They are just as sure, just as convinced, and just as wrong.

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Some have argued that since “science” (or, more properly, the scientific method) does not currently provide an overarching and all-inclusive description of reality, we therefore need God to explain what science cannot. To this argument, I offer the following rebuttals:

1. The proper question is not does science offer an overarching and all-inclusive description of reality, but whether it can offer such a description. Just because we can't explain everything at the moment doesn't mean we won't ever be able to.


2. This is a false dichotomy. Even if science can't explain everything about everything, that doesn't mean that religion can (or that it can explain the "gaps" where science fails). Made up stories by ancient civilizations have no claim whatsoever to any sort of explanatory authority.

In other words, the scientific method is the only way we can explain anything about anything. If something can't be explained via the scientific method, it can't be explained, period. Lot's of room for ideas, suggestions and general wishful thinking, true, but not actual explanations.

The Fine Tuned Universe

A frequent argument used to prove the existence of God (or some form of God, at least) is the so-called “Fine Tuned Universe” argument.  In a nutshell, the argument is that the universe is so perfectly and improbably “tuned” to support life (human life in particular) that there’s no way it could have happened just by chance.  Some have phrased the argument more particularly as follows:

The entire universe is governed by 6 mathematical constants:

1.      The ratio of electromagnetic force to gravitational force between two electrons

2.      The structural constant that determines how various atoms are formed from hydrogen

3.      The cosmological constant

4.      The cosmic anti-gravity force

5.      The value that determines how tightly clusters of galaxies are bound together

6.      The number of spatial dimensions in the universe

If the value of any of these constants had been off by even an almost infinitesimal degree, a universe like ours, that’s capable of supporting life, would not exist.  The odds of each of these constants just happening to all be exactly what is needed to support life, purely by coincidence, is infinitesimally small.  Therefore, they must have all be set on purpose by an intelligent being who wanted them to be that way.

There are (at least) four huge problems with the "fine tuning" argument that I can come up with:

1.      The argument assumes that the values of the various constants supposedly required for the universe to be capable of supporting life could, in fact, have possibly been different than what they actually are. It's not "fine tuning" if there were no other options available.

2.      There's a huge difference between "capable of sustaining life" and "capable of sustaining life as we know it." Even if the various constants could have had some other values, who is to say that some other form of life wouldn't have arisen instead?  In other words, it’s more accurate to say that life evolved to fit the way the universe is rather than saying the universe was designed to support the life that would eventually evolve within it.

3.      For a universe that is supposedly "finely tuned" to support life, it seems awfully strange that the vast majority of said universe is not, in fact, capable of sustaining life.  Even here on Earth, there are plenty of regions totally inhospitable to life.  And what about all the other planets in the solar system?  And the vast emptiness of interstellar space?  What about planets near supernovas and black holes?

4.      What makes life so special? Why not say the universe has been finely tuned to support the existence of diamonds? Or black holes? Or the rings around Saturn?  All of these things (let alone the vast multitude of non-human life on this planet such as insects) are also only possible because the universe is exactly the way it is.

I like to compare the fine tuning argument to the odds of my own existence given the vagaries of my ancestry. In order for me to be here in exactly the way I am, every one of my ancestors over the entire course of human history must have met and mated with the exact right person. If my great-great-grandmother on my father's side had married the boy her parents had forbidden her to marry instead of the man they approved of, I might have a different shaped nose, no genetic disposition to diabetes, bigger feet, etc. Or I might not have been born at all. In fact, given the size of the human population throughout time and the size of the mating pool, the odds of every single one of my ancestors mating with the exact person they did is so ridiculously low that it can't have happened by chance.

No, it's crystal clear that some external force must have been guiding each and every ancestor from the dawn of time until my mother met my father, ensuring that they met and mated exactly on schedule (did I mention the two miscarriages my mother had before having me?) In fact, given the fact that many of my ancestors traveled across the globe before meeting each other due to various political upheavals, I think it's fair to say that the majority of human history was manipulated by this external force in order to ensure that I would be born exactly the way I was, small feet, diabetes and all.

Except, of course, that had anything been different in the past then the outcome would have been different and I wouldn't be here discussing it.  If you tried to estimate in advance (say, 10,000 years ago) the odds of me coming out exactly the way I did, the odds would be ridiculously, impossibly small.  But if you try to estimate the odds now of me turning out the way I did based on my past ancestry, the odds are exactly 1:1.

Another analogy I have heard compares the improbability of the universe turning out just the way it did to the improbability of someone dealing out a shuffled deck of cards and just happening to lay down a complete suit (e.g., all clubs, all hearts, etc.).  From a purely mathematical standpoint, the odds of doing this from a shuffled deck of cards are 635,013,559,600 to one.  Which is, of course, incredibly improbable and you would be right to suspect that the dealer had somehow rigged the deck in his favor.

Except… let’s say I deal out thirteen cards from a shuffled deck and get a totally random mixture of hearts, clubs, diamonds and spades.  What are the odds that I laid down the exact combination of cards that I did?  Still 635,013,559,600 to one.  How can this happen? Well, it's all because 635 billion to 1 against was the chance of getting it right before the cards were dealt. In fact, now they've been dealt, the probability is actually 1. Talking about how improbable something was that has actually happened already is not helpful.

Similarly, one can look at a lottery where the odds of any one person winning may be 250,000,000 to 1, but the probability of somebody winning the lottery is pretty close to 1 before the drawing and exactly 1 after somebody actually does win it.

In terms of the universe, nobody was around before it began to estimate the probability that things would be as they are today. Had there been someone, then they'd have calculated a very, very slim probability indeed. But here's a universe and here we are in it. The probability of this having occurred is exactly 1.

Again, there are two possibilities. Either the universe was made just to suit life, or else life evolved to fit the way the universe is.

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One other point to consider...  Let's assume that the "fine tuned universe" argument  is actually correct and that the odds of the universe turning out the way it did by chance are mind-bogglingly, infinitesimally small (further assuming that it did, in fact, happen by chance and not because of some immutable laws of nature).  How can you say that the odds are any better of it being created by some timeless, immaterial being whose very nature would contradict all we know about existence?  How would you even go about calculating those odds?  Regardless of how unlikely a naturally caused universe is, you have to first show that a supernatural cause is even possible before you can argue that it is plausible (let alone more probable than a naturally cased universe).

Absence of Evidence IS Evidence of Absence

It has often been said that there is no way to prove a negative and therefore it is impossible to ever prove that God does not exist.  Or, as it is often phrased, “absence of evidence is not evidence of absence.”  In fact, however, as an atheist I am not trying to prove the non-existence of God.  At most, I am trying to disprove his existence, which is a whole other kettle of fish as far as I’m concerned.  Or, to put it another way, absence of evidence is evidence of absence when the evidence required to prove something is missing.

Let’s say, for example, I claim that a full-size adult African elephant is living in my backyard tool shed.  If such a thing were true, there would necessarily be certain evidence of the fact.  I would need to have, for example, an unusually large tool shed at the very least.  You would expect to hear the occasional trumpeting sounds at odd hours of the day and night.  There would be some indication that large quantities of hay were being delivered and that copious amounts of waste products were being removed on a regular basis.  A certain elephanty smell would be unmistakable as it wafted through the air.  And, above all, you would expect to actually see the elephant if you opened the door and looked in.

Keeping all that in mind, the fact that my tool shed is barely five feet wide would be an indication that maybe I don’t have a full-size elephant there after all.  The fact that nobody has ever heard, smelled or seen the elephant would be telling, as would be the fact that there is no indication of any hay deliveries or waste removal going on.  In sum, the lack of all the evidence of an elephant that should be there is conclusive proof that I do not, in fact, have an elephant in my shed.  Unless, of course, I want to argue that my elephant is a magical, invisible, shape-changing elephant that subsists only on air, excretes only sunshine, is very shy and hides in another dimension whenever anybody opens the door.  In which case, the only proper response is that the creature I have described can’t even properly be called an elephant in the first place assuming it even exists.

The same logic applies with regard to disproving the existence of God.  If God exists – at least the God as described in various scriptures and actually worshiped by those who claim to be religious – then there would necessarily be specific evidence of his existence.  All prayers offered to God in faith would be granted, for example, since this is what the Bible explicitly promises (granted, mind you, and not just “answered”).  Prophecies made in God’s name would unequivocally and unerringly come to pass in exactly the way they were prophesied to occur.  Miraculous events performed by God, including the creation of the entire universe in six days, the flood in Noah’s time, etc., would all be verifiable by modern science instead of being completely contradicted.  And yet, time and again, every place where there should be evidence to support the existence of God, it is mysteriously lacking.

Of course, some would argue that God’s existence requires no evidence because God is an immaterial being that exists wholly outside space and time and that once he created the universe he has had no interaction with it or us ever since and doesn’t expect us to worship or fear or obey or even acknowledge it in any way.  And that’s perfectly true if you want to define God that way, except that it’s most definitely NOT the way God is actually described in the scriptures and is not a God that is actually worshiped by anybody.