Preliminary Observations
Preliminary Observations
Before I interact with this argument, I want to make some preliminary observations. First, this argument is the best because it supports the conclusion to a degree. Aspects of the universe as we know it fit better with a naturalistic worldview than with a theistic worldview, and these aspects raise the likelihood that atheism is true. The second observation is that this argument does not aim to prove that God does not exist. Rather it aims to show that it is more likely that God does not exist than that He does. It is an evidential argument. Dawkins is right when he insists, in many places throughout his book, that he is not providing a watertight proof that God does not exist. One cannot prove God's existence or nonexistence. The reason watertight proof is not to be found is not because claims about God have some special status. Arguments for the claim that God exists (or does not exist) are philosophical arguments, and philosophical arguments are almost never watertight proofs. Watertight proofs are found largely in mathematics and logic. Nearly every philosophical claim and every philosophical argument are evidential. There are always premises that are not established beyond the possibility of doubt.
Not only are philosophical disputes evidential in nature; they are cumulative as well. In investigating the case for some philosophical claim such as the existence of God, we take all of the evidential arguments together and try to determine in which direction the total case points. Some arguments or lines of evidence point in one direction, while others point in the opposite direction. The cumulative nature of arguments is common throughout the disciplines as well. One line of argument by itself rarely establishes some significant claim with a high degree of confirmation. Dawkins is right to develop this argument along evidential lines in this way.
Third, this argument is about fittingness. The argument claims that ours is the sort of universe that fits better with the view that there is no God. It also claims that the universe as we find it does not fit as well with the existence of God. In this way we can test our two worldviews. We can figure out what sort of universe best fits with each, and we can see through empirical and other means whether the nature of the universe fits better with one theory or the other.
It is important to clarify the notion of fittingness that is at work. The issue of whether some observation fits or does not fit with a claim or a theory can be called an issue of connectedness. Connectedness comes in degrees. An observation connects more or less well with the theory or claim in question. There is little precision here, but we can recognize different general levels of connectedness and, consequently, different strengths of connectedness claims. For example, to say that some theory requires some claim be true or that some fact requires a certain theory be true is a tight level of connectedness. We can find such a tight level positively or negatively. For example, some philosophers have argued that the existence of God requires that the universe have no evil in it at all. This claim means, of course, that the existence of evil is incompatible with theism.4 This kind of requirement is the highest level of connectedness that can be proposed.
A moderate level of connectedness involves expectations. Any theory leads us to expect certain things to hold and other things not to hold. These things may not be required (such that their not holding is incompatible with the theory), but the expectation can be strong. One rule of thumb that may indicate some feature is to be expected if a theory is true is if the lack of that feature would be at all surprising given the truth of the theory.
There is a level of connectedness that is even less tight than expectation. Dawkins's argument trades on this level. It is the level of fittingness. Certain observations fit better with one theory than with another, even if the theory would not lead us to expect the details of the observation. Human interaction often appeals to this sort of connectedness. You may have no reason to expect to see me in Starbucks, but it certainly fits with what you know about me (if you know anything about me at all!).
The advantage of taking Dawkins's argument as one concerning fittingness rather than expectation is that the argument is for a weaker claim. If he is putting forward a weaker claim, challenging it is more difficult. Raising objections to strong claims (such as that evil is incompatible with theism) is not difficult. One has only to undermine the strong connection. A weaker claim, however, is more difficult to challenge. Dawkins's argument, because it is based on claims about fittingness, is a stronger argument.