We are constantly arguing about existence, god, and the nature of belief. Those who are religious don't understand what drives the non-believer and those who are non-believers frequently are mystified by those who are certain that god exists. The argument has persisted throughout mankind's existence and will probably continue for many centuries to come.
The difficulty with these arguments are that they are based on a false premise. The argument over god is actually an argument that arises because of sentience. Sentience is both, in religious terms, a blessing and a curse. In scientific terminology, it is an evolutionary imperative to allow for future planning. In either parlance, it allows humankind, of all the species on earth, to have knowledge of the beginning and end of life. It allows us to know that we will die. It allows us to fear that unknown.
When we have that type of fear, self-preservation instincts kick in. It becomes important to be able to satisfactorily explain what is going to happen to us at the point of death. Even prehistoric man, those who preceded homo neanderthalis, may have had primitive burial rituals and may have interred their dead with the hope of an afterlife. By the time of the Neanderthal, that practice was fairly well entrenched. When Homo Sapiens became dominant and other hominids became extinct, the belief in gods and an afterlife was deeply ingrained in the lives of the tribal peoples. Gods controlled the elements and the more powerful the element, the more powerful the god.
Gods were created to protect humankind. Everyone had their own totem or god. When one people conquered another, the defeated people abandoned their gods and accepted the more powerful, more protecting gods of the victors. The new gods would get them to eternal life.
It is easy to see how religions have come and gone throughout history and it is easy to see how monotheistic religions eventually became transcendent under this human sentience theory. When science was primitive, the only way humans could understand death was to place that end of life in the hands of a almighty, all-powerful god. When human knowledge was earth-centric and history was what was passed down orally through generations, an omnipotent god that none could physically interact with until death was a comforting thought. The knowledge that we were the only creatures on earth with this knowledge set us apart.
But we've progressed and evolved. We now understand the mechanism of death and we understand that the energy of the universe changes for all matter. For those who accept science, the concept of a god to take care of us post-death is not necessary. For those of us who accept science, the concepts of morality, goodness, honesty, and love are human genetic qualities and not there because they were mandated by some god created doctrine or tablet. It is our sentience that allows us to understand that there is no need to fear death and therefore, there is no need to create a god to ease me to a post-life that I understand scientifically is not there.
For the believer, sentience brings just the opposite reaction. Knowledge is given to us by this god and only is there to ease our way to our acceptance of him prior to our death. Once we die, there is no science, only the kingdom of heaven. It is a completely opposite view of sentience.
Some scientists have indicated that man is equipped with a "god gene". Something in our genetic make-up that allows us to believe in the existence of a god figure. I am certain that the "god-gene" is, in fact, the gene that controls sentience. That knowledge is powerful. It thrives in humans. It is strongest when the exposure to science is at it's lowest, as indicated by the statistics that show that the more highly educated the individual might be, the less religious the person is. It is part of humankind's survival strategy that has allowed him to become the dominant species on this planet.
But for all the good that the sentience gene does us, it also leads to strife. It leads to the argument between the believer and the non-believer. It leads to the wars between the religions. It leads to the forced conversion to the "true belief". We can only hope, that as we mature and evolve, we will all come to understand how the sentience gene works in our own bodies and that we all control it in a way that not only benefits us, but also the rest of humanity.