I wanted to take a brief pause from the Fine Tuning posts while this topic was still fresh in my head.
Last week at the monthly meeting of our SMASH group (Sarasota Manatee Atheists & Secular Humanists), one of the members made a couple of statements I wanted to expand upon in more detail. Specifically, the claim was made that the question "Does God exist?" is purely a philosophical question and science can not be used to determine whether God exists.
Of course I disagree with that, but maybe there's some bias involved on both ends since the member who made the statement is a philosophy professor and I'm a scientist, LOL. However, looking at the issue as objectively as possible I can't help to think that without question science can address the likelihood of whether a specific God exists, like the God(s) of Christianity.
For starters, numerous Christian apologists (e.g., William Lane Craig, Dinesh D'Souza, Frank Tipler, etc.) are always trying to use science to prove the existence of God. In fact, the fine tuning argument (see my previous posts) is one of their favorites, and Tipler even wrote a book called the "Physics of Christianity". Additionally, science can also be used to debunk the claims of theists. For example, evolution theory disproves creationism. Natural selection debunks claims of intelligent design.
There are also several ways science can be used to determine whether God exists. The most obvious one would be if cosmologists could find a natural cause for the formation of the universe. Another one would be if chemists or biologists could determine how life could form from non-life. If natural solutions to these problems were found then that would certainly lower the probability of the existence of God.
Science could also be used to assess the probability of the existence of a specific God, like the God(s) of the Bible. For example, if the creation story in Genesis was found by modern science to be true, well then the probability of the existence of God would be high. However, if the creation story is proven nonsense by astronomers, anthropologists, archaeologists, geologists, and biologists, then the probability of the Biblical God would much lower. As another example consider the effects of prayer, which can be scientifically evaluated. In the New Testament Jesus said that if you pray and have faith you will receive what you ask. So if praying really works then that would be a positive sign that Jesus really exists. However if the opposite is true that praying has no effect, then that would lower the probability that Jesus exists. One other example to drive the point home is that God is often characterized as having certain properties (e.g., all-powerful and all-loving). Well if needless suffering exists then wouldn't that wouldn't that lower the probability of an all-powerful and all-loving God, and if starvation on earth were to suddenly end with food falling from the sky wouldn't that increase the probability of God's existence? Lastly, it's often said that absence of evidence is not evidence of absence. However, this is not necessarily true. For example, if there is no evidence that a goldfish is swimming in the lemon tea that I'm drinking right now, then that would be pretty good evidence that there really are no goldfish in my drink. Likewise, an all-powerful God would easily have the power to come down and say hello to us. The fact that we have no video recording of such an event does lower the probability that a God exists. So by considering all the potential factors, a rational person through science, logic, observation and reason should be able to assess the probability of God's existence.
In a way, trying to assess whether God exists is a similar problem in determining whether your home has any termites. The pest expert can perform a visual inspection to see if there are any living or dead termites. The expert can look for signs of termite damage (i.e., chewed wood, sagging floors, sawdust). The expert can look for mud tubes on the home's foundation. After assessing the evidence the pest control expert can form an opinion on whether there are any termites in the home. Even with the lack of any sign of problems, he may never be able to state with 100% certainty that there there are NO termites in the home since there are areas he may not be able to inspect. However, the expert should be able to make a judgment on whether termites are a problem.
In the same way a person can assess the evidence for the existence of a specific God. Does praying work? Did they see God? Did they witness a supernatural miracle? Are the scriptures accurate and in concordance with modern science? Did scientists discover how life forms from non-life? These are the many ways we can use science, observation and reason to assess whether a God exists. If the question of God's existence is purely a philosophical question, and if it wasn't possible to evaluate the evidence for the existence of God, then atheism would be nothing more than a faith-based viewpoint (like Christianity) rather than one based on critical thinking, objective analysis and scientific application that most atheists believe.