Notes on Articles of Faith

Why is believing in reality an article of faith?

Because everything a human experiences is through the filter of human experience.
Whether walking in a field or taking drugs in an isolation chamber, the experience is always human. It occurs in a human body which has a human mind. Almost all humans are non-feral. That is they have some sort of education and some sort of way of thinking about the world. This is added to the filter. Even scientific concepts like energy, matter, cause and effect are totally human constructs. Whatever is happening in the universe and the "unaverse" (the inner world of your sole mind and body) cannot be known, except through the human filter. So, every the most obvious truths are articles of faith. The good news is that we need never stray from the most obvious truths. Doing so is at our own peril.