I think if you are a thinking life form, and not a robot, then you will know that God exists because you are made out of the same living substrate as God. I’ve known about God since early childhood, and at the time I had not had any exposure to religion or spirituality whatsoever. It almost seems strange to me that people would even ask the question, when they should already know the answer. If they are not robots, then they must be in active denial, or have some as yet unknown external influence upon them.