Actually Phi is exactly correct. One cannot prove a negative, so you have to be willing to accept that anything is possible as long as it is not in violation of things which have already been investigated using an evidence based methodology. No other assumption is logical. For example one could neither be certain of, nor certain of the lack of the existence of aliens. One can be relatively certain that young-earth creationism is bullshit, however, because geology, biology, and many other areas of study have produced absolutely insurmountable evidence contradicting young-earth creationism.
Until there is evidence for something, there is no reason to believe nor evidence not to believe it, and no need to prove it unless you are serious about finding out if your opinions have merit. Like you, I am a fan of Occam's Razor, but I must say that its application can hamper you in the area of martial arts and philosophy. In those areas it is often prescribed to hold your mind open to a wide range of possibilities so that you don't miss something which your preconceptions might have had you label impossible.
But we're not talking about martial arts or philosophy. Corky is asserting the existence of a specific force/power/energy which can produce measurable effects in the physical world; he is making a scientific assertion. This is not a subjective artistic or philosophical statement. There is no reason to believe him -- and ample reason not to -- until he provides verifiable scientific evidence for his assertion.