Originally Posted by e90im
Physical nature? As opposed to what?
What is the difference between not being able to prove something exists and the non-existing?
Since when is ignorance truth?
Columbus didn't know Native Americans existed, did they? Yes. Seeing doesn't mean existing.
Does air exist? Can you see feel hear or touch it? no, but it is there.
Do aliens exist on other planets? We do not know, does that mean that they do not exist?