I am a theorist. That means that I mostly deal with the theory of something, and that I am more concerned with argument than I am with evidence. Indeed, I have a disinterest in evidence if it is not properly explained, because I know how easy it is the manipulate facts to give the appearance of truth. So, for this reason I may not be the best person to discuss the Teleological Argument, or the Argument for Design, because it is a very evidence laden argument.
However, I am also perhaps the best person to read a short essay on the subject, for the very simple reason that I can tell you that if you have come to a conclusion in regards to this argument after reading a couple of books, or essays, or after hearing two men debate on the issue, then you have never really considered it. I am not a theorist because I think evidence is unimportant. Indeed evidence is the very thing that grounds one's beliefs in reality. I am a theorist instead because I recognize that it takes a considerable amount of time to sort through evidence, and I am just as nervous about someone accepting my argument because I have presented a lot of contextless facts as I am someone rejecting it.
Therefore I would encourage anyone reading this to go and examine the evidence for yourself. I highly recommend Case for a Creator by Lee Strobel as a primer, but only as a primer. I recommend it not because it argues the point well, but because it points to sources that one can go and examine for one's self.
A second point that I believe is important is understanding the difference between deduction and induction. Deduction is the logical process where a conclusion is demonstrated to necessarily come from the premises. Induction is the logical process where a conclusion is demonstrated to probably come from the premises. I bring this up because all arguments for and against the existence of God are examples of induction. God is neither falsifiable or provable, unless He chooses to be of course. I have often noticed that atheists seem to insist on deductive arguments for God's existence yet offer inductive arguments against His existence, which is simply special pleading. Yet this is precisely why I have been talking about arguments for God's existence rather than proofs.
Additionally, it is also true that all of science is a process of induction. This is why the highest classification of scientific thought is theory (most scientists today have rejected the idea of scientific law). The value of a scietific theory is not how definate the claim is, but how explanatory it is. This means that it explains the evidence better than other claims, not that it has been proven. Indeed the scientific method, as powerful a process as it is, is a formalization of guess and check. That is not a knock on it, but it is important in understanding that as we consider this argument, and are not assessing if it is the only possible conclusion, but if it is the best conclusion.
THE TELEOLOGICAL ARGUMENT
A Prima Facie case is the first step to any actual argument. It means that there appears on the surface to be legitmacy to the argument. The prima facie case is not the conclusion, but the first step in presenting an argument. In other words, it demonstrates that the argument is worth hearing out.
The prima facie case for the teleological argument is usually presented as an analogy. Consider a man, he living without exposure to modern times, is walking through a jungle, and he comes across a watch. He picks it up and examines it. He then concludes that this object was fashioned by someone with a purpose; it could not have formed naturally.
The teleological argument makes the same hypothesis about the nature itself. The above analogy is basicly arguing that there are signs which points to a designer: order, focused functionality, language and uniqueness. These attributes denotes purpose behind something, and purpose implies a designer.
The Privileged Planet
One thing that all atheists insist on is that there is life on other planets. After all, if life is simply the result of chemical reactions, then with the right mix, it is an inevitability Originally it was assumed that there must be life in our solar system, but as time went on, we began to realize how unlikely that was. We then assumed in was in the next nearest star, but again, that not seems unlikely. It seems that the more we learn about life, and the more we learn about space, the rarer life seems to be.
The main reason for this is that even if life is merely chemical reactions, proper conditions for those reactions is actually quite rare, not to mention a variety of other factors necessary for life to be sustained. First of all, all of the necessary chemicals (especially water and carbon of course). Also, a magnetic field, atmosphere, plate tetonics, the carbon cycle, a large moon for maintaining ocean currents and a tilted axis, proper tilted rotation, stable circular orbits (for liquid water), and near by gas giants to pull in asteroids and other hazards. As for the sun, it needs to be the appropriate distance from other stars (for stable orbits and less radiation), large enough (most stars are smaller than Sol), emit the right kind of light for photosynthesis to be possible and other phenomena, stable, having a circular orbit in the galaxy, and being in a same zone between the arms of a spiral galaxy. The above list is not comprehensive, but it is important to note that everything listed above is rare. These are all unusual features.
Quite frankly I don't understand how many who think life is common in the universe are actually environmentalists. Either life is fragile, or it isn't. But in either case, it seems like we are uniquely positioned to have life, which implies that the Earth was designed with life in mind.
Irreducible complexity (IC) is often misunderstood. First of all, it is not a Creationist argument, though it is used by Creationists such as myself. Dr. Michael Behe who first proposed it merely proposed that evolution needs to be managed by an intelligence. Its point is merely that evolution cannot account for all biological phenomenon.
However, before I go on, I need to define it. IC refers directly to proteinic systems which exist in our bodies. This is important because or DNA is primarily a recipe book for proteins*. Indeed, when we say that we are carbon-based life-forms, we are in fact referring to proteins, which are long chains of amino acids and are composed mostly of carbon. Proteins are kind of the biological molecule because they not only can be so large, but they are so variable. Most of the functions in are bodies are done by a collection of proteins working together. This also means that an variation in DNA influences the production of proteins.
[* When I say "primarily" here, I am referring also to developmental regulatory genes which reference a system of proteins instead of a single protein. And by system of proteins, I mean activation of other genes]
IC is most easily defined as a system which every component is necessary for the operation of that system. Here is where we have the second most common misunderstanding, which is what I like to call the bicycle bell fallacy. If you have an IC system, you can't subtract from it, but you can add. Most systems in the body which have IC, are actually IC systems with a couple of things added to them, like a bike with tassels and a bell. However, you can't disprove the IC of a bike by taking the bell off, and many do that. In order to prove that a system isn't IC, you have to show that the intermediate stages of development are viable systems, that is systems that actually accomplish something. Otherwise, you don't have evolution.
However, this post isn't about proving IC, or disproving Darwinism. My point is that this kind of complexity implies a designer of these systems.
In science there are several mathematical constants. All of these has to be precisely what they are in order for the universe to exist as it is, and for life to be possible in it. This includes the strong nuclear force, the gravitational constant, the cosmological constant, the electromagnetic force, and many more.
There have been two defenses for this. One is the multiverse, which I dealt with on an earlier post. The second is called the Anthropic Principle. It simply states that if the universe were not capable of life, then we wouldn't be able to comment on it. Therefore no explanation is necessary. In other words, the question is merely a consequence of the existence of our minds, rather than something that actually is based on reality. However, this is nonsense for the basic reason that in any other instance, when something unlikely occurs, we look for a reason. Without light from the sun, we wouldn't have existed either, but that doesn't mean that asking how the sun gives off this light is somehow illegitimate.
As I said at the beginning, many people have presented this arguement better than I could. Additionally, due to how long it took to get to writing this, I have to admit that I merely pounded out the last few sections to get this done. Please look into other sources to better understand the details to this argument.