God does not exist

At this point in my life the nonexistence of God feels so obvious that I'm not inclined to give a detailed argument.

The paradigmatic "God" is an all-knowing, all-powerful, all-good being, though polytheistic religions have believed in a much wider variety of gods. Humans have a powerful urge to make sense of things, which has been adaptive for us in finding generalizations, outfoxing foes and prey, and ultimately leading to our impressive store of scientific knowledge. However, on many big questions there's not enough data to really make sense of things, so we make things up. That includes belief in spirits, gods, and ultimately, God. But science has explained a great many things that were before explainable only by God. Evolution by natural selection was an especially profound discovery. Our need to make sense of the big questions and long historical tradition leave many people still believing in God. But if we take the scientific perspective of hypotheses, predictions, and repeatable observations, no hint of an actual God is to be found.

I don't claim science understands everything. The most profound thing we know of that it does not understand is conscious experience -- why things have a "seemingness". There is no limit to what else might exist that we have no knowledge of. The Christian God might conceivably exist, but we have no evidence for it. Pascal's wager is useless, and here's why: for any imaginable God who will reward you for doing X and punish you for doing Y, there is an anti-God with the exact opposite preferences -- he will punish you for doing X and reward you for doing Y. If there is some God, we know absolutely nothing about him, which for practical purposes means he does not exist.

In a world with no inherent, objective meaning, we choose our framework for how to live a good life (often simply accepting what our family, friends and society believe). Choosing to believe in God is no worse a choice than any other. Studies suggest people who believe in God are happier and have improved measures of well-being. I suppose such a choice could be called faith. But the scientific method has given us tools for discovering a great many regularities in the world and dismissing ideas that are not supported by fact. Those who believe in God, if they are honest, should realize it is an arbitrary choice without support from the extremely impressive edifice of science.

And while believers may not want to focus on the arbitrariness of their choice, they should at least have humility, recognizing others have chosen different frameworks with no less support than theirs. In a pluralistic society, we have rules about tolerance for a wide variety of personal choices as long as they don't encroach on others' freedom. So what I ask of believers is that when they do affect the lives of others with different beliefs, via laws or their private behavior, they should have a secular justification. This obviously prohibits burning heretics or chopping off the heads of infidels, but it also argues against a state religion or discrimination against any group based on their private beliefs.

God does not actually exist. Choose to believe in him if you wish, just also have humility to understand that other good and reasonable people have made other choices, whether believing in some other conception of God or no God at all, which need to be respected.