Everything that man holds as valid data has been labeled as such because it, presumably, has been put to and through a test of science. What does a test of science truly prove? It proves that man, in his quest for knowledge, has tested a theory that in a controlled environment can provide an expected result. What I am interested in is the perception of that result. What man holds true, most commonly, as fact are those things in which he/she can verify with the tools provided to the human body for the express purpose of interaction and physical manipulation of the environment; the five senses.
As a general rule, it seems that man will most often dismiss that which he cannot see, touch, feel, taste or hear. For the purpose of argument, I will include emotions under the category of "feel" because emotion most definitely is registered within the body and causes physical reaction in much the same way as other senses.
If the above is true then the next logical step would appear to be that human kind believes itself (largely) to be the center of the universe. If we believe only in things that we, ourselves, can experience then we also must believe that things that we are not equipped to experience are non existent.
The opposite of a human centric universe would, I propose, be frightening to a great many people. What if, for example, there were many things outside of our realm of ability to interpret (5 senses), existing in the same dimensional plane that mankind exists in, that can see, feel, hear, taste and touch us without our knowing a thing about it? Is it arrogant of us to assume that because we cannot 'sense' something then it does not exist? Is it pointless to argue the possibility because due to our limitations (are they really?) we can never know of them anyways? It can be rather mind boggling to attempt to reconcile the two ideas.

Are we equipped with more senses than five?