Only because your warped brain cannot see something intelligent if it bit you on the nose. And intelligent things tend not to bite people on the nose.
Right, of course you do not know!
I'll do you one better.
Of course you do not know if something is NONEXISTENT but you can be reasonably certain if something is EXISTENT. But what about the Evil Genius theory (sometimes called the Evil Demon theory)? Suppose this is all an illusion. Well, the fact remains if we were to strip all of this away, we'd just have some sort of trickster and a person being tricked. That is, there is an advantage to something existing versus it not existing. Further, you can see, feel, and smell things that are real, barring the notion that reality is an illusion.
Therefore, if God is the creator of the universe, which the Bible canonically declares as self-explanatory since to create the universe, tou would have to be God, then by experiencing the universe, and the natural world, you have a pretty good proof for God. Go get friendly with trees and get some poison ivy, and you'll know God exists. You'll also know he has a warped sense of humor for inventing poison ivy.
I have a theory, which I will henceforth call the Las Vegas theory. It goes like this. In Las Vegas, most of the casinos seem to have no windows. It like, they want you to be lost so you'll go in and gamble, and the surest way to make you lose your bearing is to cut you off from the outside world. Likewise, people living in big cities have a sort of tunnel vision where they think they are better educated than Those People (ummmm you can commute to a good college) who they imagine have buckteeth and look like those from Deliverance, and they think because they have big shopd that nothing much happens in small towns so they're deprived (ummmm again, we have Amazon and a number of mail order systems, there is no reason to ever go to the cramped polluted city in order to shop, but if so we can do all our business in a day trip). On the other hand, people in cities are statistically higher likelihood of being more atheist. Why is this? Well, they'll tell you it has to do with their "education" but frankly I not only regard them as brainwashed but also not smart enough to get away from places that are giving them a number of medical and spiritual disorders. Education isn't what it's cracked up to be if it doesn't allow us to question what we've been taught. But more importantly, like that box where you can only see roulette or slots or flickering lights, the inside of the city cuts you off from most of the chirping of birds, the bleating of goats, and the "quiet" chirping of cicadas. They only see inside, where all around them is human greed and evil. Where politicians have made laws, and these laws actually have to be followed. Does a guy on a subsistence farm 1000 miles from anyone have to wear a COVID mask? Not on your life! What other people want has nothing to do with him, he grows his crops, you can masturbate outside for all anyone cares. Meanwhile, people living in the city only see the worst of humanity, and the Accuser is able to work on them, undermining their faifh in God and other humans. They see a funhouse version of reality where everyone is hunched over. They don't see outside the four walls of the prison built for their mind.
But I have successfully escaped my mind. Ahahahahaha!!! (Runs away like a madman)
Yeah yeah, that's not your real name. Everyone online is a girl pretending to be a guy or a guy pretending to be a girl, or a musical instrument pretending to be a real boy. Just as Farmerman isn't a real superhero. After all, if we haven't seen it personally, it must not be real.