The most distinguishing aspect of belief is that there is the possibility that the thing one believes is false. We all believe a few things, especially what we'll have for dinner tomorrow. In an astonishing display of denial, many supernaturalists insist that evolution is a belief. It's true that we'll never have a complete fossil record of every generation of every species, thus we are forced to speculate and thus believe certain specific scenarios took place. But we don't have to believe in evolution as a whole. We know that mutations take place and we know that nature provides pressure to select the most adapt individuals, thus we know evolution is a fact.
The two main arguments about knowing things from science and philosophy come from the quantum and matrix worlds. In the quantum world, pundits claim that since we can not know where a particle is or how fast it's going with absolute certainty we are forced to believe in its existence. Luckily most of the particles we interact with are clustered up into atoms and molecules. We don't have to believe they're there, we just have to except that our knowledge of they're exact location will always remain undetermined.
In the Matrix multiuniverse adherents claim that we can only believe because we interpret the world through our senses and our senses can be fooled. Therefor, we can never know what is real and what is being feed into our brain by a master programmer. And for that matter, we might not even be humans. We might be independent programs in a massive virtual reality program run by gamers one flight up in reality. Although I know that thinking is proof of being, we are not dependent on ourselves for proof of reality. The entire objective universe is proof of existence and it reveals a constancy through cause and effect. But I can hear Morpheus whisper, "The matrix has laws like gravity and stuff like matter..."
The belief in gods led naturally to this computer simulation version of dysfunctional disbelief in the natural world. And just as so many theologians claimed that they are spirits stuck in a fleshy imperfect body, todays sci-fi matrixlanders subordinate to computer operators, a sentient program thinking their self human, will says to their self, I believe this reality is not real. It's an evasive argument because it's relatively impossible to disprove and assumes that artificial computer simulations exist and can be self aware. It, along with the pink unicorn and god argument, demand that total knowledge of everything be achieved to discredit it's assertion. These people, or spirits/programs, "ought" to recognize the belief aspect: It is very possible (actually relatively infinitely probable) that they are wrong. The reason is simple and revolves around reason. In both scenarios there is a master agent, a being of some sort that has intent. The reason a master agent would create sub agents (programs/sheep) that lack the information of their true situation, would be for the entertainment of watching them try and discover the truth. But seeing as though the master agent would be the one setting the rules it would be they who allowed the sub agents to discover the truth. Or as in the movie The Matrix, we would be powering the process of fooling ourselves. Thus, the sub agents (people) would simply be extensions of the master agent (god) or a completely ridiculous redundancy which will eventually burn itself up. And that would mean that not only are we not real, but the agent that created us is also not real.
Obviously we are. To believe that we need to constantly believe that we are to be is ridiculous. Programs and spirits may be useful tools in describing the complex identity we have, the only thing we'll ever have, as we rent this body and dart around in a storm of fired synapses. But there is no reason to doubt reality. I know, therefor I am.
