I believe that E=mc2. I also believe that God does not exist. I used to believe that God exists, but now I do not.
Most of what I believe is based on testimonial evidence, that is, things I heard from others. Very little of what I believe is based on direct evidence, that is, things I directly experienced myself.
For example, I believe that E=mc2 based entirely on testimonial evidence I acquired from people whom I trust, such as my physics professors. In fact, I believed that E=mc2 even before I knew what E=mc2 means. Some people, such as my physics professors, may believe E=mc2 based on direct evidence, but my belief that E=mc2 is based on testimonial evidence. For all I know from direct evidence, E could equal mc3 or mc1.7. But I don’t believe that E=mc3 or that E=mc1.7. I believe that E=mc2 because that’s what people whom I trust have told me.
Similarly, I used to believe that God exists based primarily, if not entirely, on testimonial evidence I acquired from people whom I trusted, such as my parents and my religious leaders. I’d say that my current belief in the nonexistence of God is also based primarily on testimonial evidence I acquired from people whom I trust, such as my philosophy professor and Christopher Hitchens.
My brain generates all my beliefs by performing a process I call “automatic involuntary subjective evidence weighing” or AISEW, for short. My brain automatically and involuntarily assigns different probative values to the different pieces of evidence in my possession and automatically and involuntarily weighs that evidence to automatically and involuntarily generate my beliefs.
If, at a given time, the evidence in my possession for the truth of a proposition, such as E=mc2 or God exists, outweighs the evidence in my possession against the truth of that proposition, then my brain will perform the AISEW process to automatically and involuntarily generate my belief that the proposition is true. If, at some other time, the evidence in my possession against the truth of that same proposition outweighs the evidence in my possession for the truth of that proposition, then my brain will again perform the AISEW process to automatically and involuntarily generate my belief that the proposition is false. The process is the same; only the evidence in my possession has changed.
When I used to believe that God exists, it was because I had more evidence for God’s existence than I had for God’s nonexistence. What was my evidence? The testimonies of my parents and others whom I trusted. The beauty of trees. The wonder of the human brain. Over time, I acquired evidence of God’s nonexistence, and I acquired information that affected the probative values assigned to my other evidence. I learned how evolution could explain both the beauty of trees and the wonder of the human brain. I learned that bad things happen to good people and that good things happen to bad people. As a result, at some point in my life, my brain performed the AISEW process to automatically and involuntarily tip my belief scale from theism to atheism.
I don’t know that E=mc2, but I do believe that E=mc2. When I was a theist, I didn’t know that God exists, but I did believe that God exists. As an atheist today, I don’t know that God does not exist, but I do believe that God does not exist.
Some people who believe in the existence of God say that their belief is based on faith. Some atheists (and perhaps even some theists) define that type of faith as the acceptance of God’s existence without any evidence for God’s existence or, worse, in the face of overwhelming evidence against God’s existence. That is not correct and, worse, that is not fair to theists. When I was a theist, I never said that I had no evidence for the existence of God or that I believed in the existence of God in the face of overwhelming evidence otherwise. No, I said, “Look at the beautiful trees. Look at the wonderful human brain.”
When some atheists say that theists believe in the existence of God without evidence or in the face of overwhelming evidence otherwise, what they mean is that theists believe in the existence of God without evidence that those atheists accept as evidence or in the face of overwhelming evidence that those atheists possess.
In fact, theists come to their belief in the existence of God by their brains performing the same AISEW process that is performed by the brains of atheists in generating their belief in the nonexistence of God, which is the same AISEW process that is performed by the brains of all people who believe that E=mc2 and even by the brains of those people who believe that E does not equal mc2. Brains don’t perform different processes for different types of beliefs or at different times. After all, brains are just brains, and they perform the same AISEW process all the time.
So, I used to have faith in God’s existence. I now have faith in God’s nonexistence, and I have faith that E=mc2. I didn’t and don’t know now that any of those things are true, but I did and do believe that they are true. Those beliefs were and are based on faith, where faith is just another name for the AISEW process.
And if my brain generates all my beliefs automatically and involuntarily, and if I always act according to my beliefs, then doesn’t that mean that all my actions occur automatically and involuntarily—that is, that I don’t have free will? For free will to exist, my mind must be able to exercise control over my body. In other words, my consciousness must be able to affect my brain.
In addition to believing in the nonexistence of God, I also believe in the nonexistence of my eternal soul. Like my beliefs, my consciousness, which some people refer to as my soul, is automatically and involuntarily generated by my brain and will cease to exist when my brain ceases to function—unless, of course, someone figures out how to transfer my consciousness to another brain or a machine. I wish they would hurry up.
I don’t know how my brain generates my consciousness—my awareness of self, the “I” in “I think, therefore I am”—but it does. And when my brain stops working, my consciousness will cease to be. I’m not happy about that, but I do believe that it is true.
For free will to exist, my consciousness must be able to affect my brain. I know of no science, no biology, no chemistry, no physics that would explain how consciousness, which is just a particular type of nonphysical thought generated by my brain, can in turn affect the lobes, the neurons, or even the atoms in my physical brain.
It’s easy for a theist to explain the existence of free will; it’s just another one of God’s many miracles. It’s impossible for an atheist to do so.
Do I know that free will does not exist? No. But I do believe that free will does not exist. I have faith in the absence of free will.