*Sigh*.... And here I go again getting tumbled into another one of these...

Before we begin I suggest we drop all preconceived notions on what you think God is. The simplest and most scientifically feasible answer is that God is energy. All energy in the universe, detectable and undetectable by us. So you can see how using the word "God" can confuse an argument as the word conjures up any one of the following images:
1. God
a. A being conceived as the perfect, omnipotent, omniscient originator and ruler of the universe, the principal object of faith and worship in monotheistic religions.
b. The force, effect, or a manifestation or aspect of this being.
2. A being of supernatural powers or attributes, believed in and worshiped by a people, especially a male deity thought to control some part of nature or reality.
3. An image of a supernatural being; an idol.
4. One that is worshiped, idealized, or followed: Money was their god.
5. A very handsome man.
6. A powerful ruler or despot.

The main word that irks me when describing "God" is "being." We are beings, we are entities. That which is "God" is simply the universe. We are part of this as well.

AtmanWalter, I am going to attempt to answer your question now... You want to know why things ARE as opposed to are NOT. Well what you need to understand is that those two concepts are RELATIVE. They are relative to perception, and the perceiver. What I mean by this, is that if something is beautiful to you, it is beautiful because you perceived it to be so. Another person might perceive it to be not so beautiful. Now, I know you are referring to the tangible aspect of the universe as opposed to human opinion of tangible aspects, and Im getting to that.

What you need to understand is that we(and by we, I refer to all creatures on Earth) exist in the tangible dimensions of the universe, more specifically the first 3. Pure energy exists on a far wider dimensional spectrum and has a completely different set of qualities that define what IS or ISNT. This is something that we as humans cant seem to comprehend yet.

Things exist for us, in your words they ARE, because they are comprised of matter, and matter is energy that is condensed and specialized. So when energy coallesces to a specified purpose to the point that it is then able to exist in the 3 basic dimensions that we tangible creatures can comprehend, it then becomes perceiveable to us and thus IS. So remember that just because you perceive that something ISNT... doesnt mean it truly isnt.