Andrea you make two contradictory statements the first statement is" ... atheism is NOT a belief system" then later on you state "I'm not out to prove that a god or gods don't exist ... I just don't believe they do." How can you say in one breath atheism isn't a belief system and then in the next breath say you don't believe a supreme being exists?

A belief system is the mental attitude that some proposition is true. For every given proposition, every person either has or lacks the mental attitude that it is true. Beliefs may be stronger or weaker, based on evidence or not, reasonable or irrational. Beliefs are a mental representation of the world around you — a belief about the world is the mental attitude that world is structured in some way rather than another. Beliefs are the foundation for action: if you believe something is true, you must be willing to act as if it were true; if you are unwilling to act as thought it were true, you can't really claim to believe it. This is why actions can matter much more than words.

The argument that atheism is not a belief system flies in the face of logic and fact. Here is a except in its entirety about whether or not Atheism is belief system or religion

Is Atheism a belief system or religion?

Theists usually define atheism incorrectly as a belief system. Atheism is not a belief system. Atheism is not a religion.

Atheism is a lack of belief in gods, from the original Greek meaning of "without gods." That is it. There is nothing more to it. If someone wrote a book titled "Atheism Defined," it would only be one sentence long.

Let us look at the different definitions of religion and see if atheism belongs in any of them.

1. Belief in and reverence for a supernatural power or powers regarded as creator and governor of the universe. A personal or institutionalized system grounded in such belief and worship.

No atheism resides in that definition. Atheists do not believe in a supernatural power or powers.

2. Beliefs, values, and practices based on the teachings of a spiritual leader.

Atheism does not have a spiritual leader and atheism does not have any rites or rituals (practices) around such a spiritual leader. Atheism requires no initiation, no baptism, there is no Atheist Bible (Koran, Vedas, etc) to read, no rituals that atheists must go through to join an Atheist Church (temple, mosque, synagogue, sect, etc), and no central beliefs that all atheists must adhere to in order to be "true atheists."

The common thread that ties all atheists together is a lack of belief in gods and supernatural beings. Every atheist is as unique as a fingerprint when it comes to his or her individual philosophy, convictions, and ideals.

http://www.atheists.org/atheism/About_Atheism
The author of the above is quite right in stating Atheism is not a religion or have any of the trappings of a religion., However the author does fail on providing any sort of proof that atheism is not a belief system and instead confirms it is a belief system without even realizing they are doing it with one sentence "The common thread that ties all atheists together is a lack of belief in gods and supernatural beings." The fallacy here is in equating belief system with religious belief. While all religions are a belief systems, not all belief systems are religions, a similar analogy would be "All Catholics are Christians, but not all Christians are Catholic."

So from my point of view, to say atheism is not a belief system is not only illogical but intellectually dishonest.

"In the hegemonic state there is neither right nor law; there are only directives and regulations which the director may change daily and apply with what discrimination he pleases which the wards must obey. The wards have one freedom only: to obey without asking questions. "
Ludwig von Mises -- Human Action p. 199; p. 198