Attempt at criteria for truth in a spiritual science

Traditional science relies on objective, interpersonal proof of its hypotheses, as the objective, interpersonal reality is its area of study. If knowledge of the spiritual is the opposite of knowledge of the physical, it follows that if the last need objective proof, the former needs subjective proof. We are, however, used to thinking that objective proof is the only form of proof. That without empirical evidence, knowledge is not truly possible. I will attempt to show that within the science of the spirit, such proof is possible, and indeed the only possible form of evidence.
Now, all of this presupposes the excistence of some sort of spiritual substance. I will hold that such a substance does indeed excist, but I will not argue this point here, as the genre of the blog lends itself to shorter texts. I might return to this problem at a later date, even though it is my belief that it is actually impossible to prove such a thing; it is for the individual to accept or reject at his or her own whim. I do, however, have some arguments in favor of my position on this issue, and thus may return to this in future posts.
Anyway, the excistence of some kind of spiritual substance accepted (if for nothing else, only for the sake of argument), we can move on to trying to establish a base on which to build the knowledge we seek. The first tool we have at our disposal on this quest for knowledge is logic. Any argument in support of a particular truth must be logically consistent. I do see that there are problems with this approach. First, it must be admitted that logic is a tool of traditional science, which we have just defined as the opposite of the doctrine we are trying to establish. Second, as we can not directly observe the spiritual substance, we actually have no proof that this realm is governed by logic at all; it might be entirely irrational, inaccessible to logic.
At this point, I need to formulate a second postulate to be accepted by the reader. In addition to assuming that there is such a thing as a spiritual substance, we must also assume that we have access to this substance in some way. Without such access, everything we are trying to achieve here will be meaningless. The only way I can think of that such access could be possible is through the soul, which idea is the basis for the idea of a spiritual substance in the first place. The theory must be, that in some way (I will get back to this later), our souls are the part of us that belongs to the spiritual realm. The part of our consciousness that lies one level above our thoughts. We have access to this world through such excercises as meditation or other techniques for achieving what is called altered states of consciousness. In these states, where normal consciousness and the mind are removed from our being, we experience pure excistence within our own souls, and thus observe its nature. It is also what we catch a glimpse of when we experience epiphanies, short feelings of complete knowledge that evaporates as quickly as it materialised.
I stated earlier that evidence of spiritual truth must be subjective. What is meant by this is that such knowledge can only be valid for the subject, that is, you can never prove to someone else that your vision of the spirit is true or valid. It can only be proven within the confines of the self. Such knowledge can still be communicated, though, but each individual, when exposed to something claimed as a spiritual truth, must decide for himself whether it is valid or not. Keep in mind, however, that I am still not claiming that each and everyone is entitled to his or her own version of the truth, and that all religious-dogmatic superstitions can be valid as spiritual truths as long as the individual decides for him or herself that this is what he or she believes in because it is written.
No, this is where I arrive at my main point: What must be devised, is a method. A method through which the individual can test any claim to spiritual truth he or she is confronted with. Now, the method itself must be interpersonal, but it is of such a nature that it can only be applied subjectively. My first proposition for an element in such a guide is the principle of irreversability, as it might be called. Certain ideas, once scrutinized thouroughly, can not be rejected. A most obvious example of this kind of thruth is mathematics. Once you have learned a mathematical axiom, it can not be unlearned. It is an inescapable truth once accepted. This also presupposes an open mind, and a sincere willingness and perpetual readyness to abandon your convictions.
A cuple of issues must be addressed. First (indeed for this post, I think it must be the last, I must continue on this later), philosophical, ethical or metaphysical claims are not the same as mathematical truths. They are much more complex, and thus a lot harder to judge according to the method I describe above. In fact, any metaphysical claim, such as "God is red", can not be absolutely proven or disproven through this method, but in fact, this is not the point here. It is not the point of this method to enable one to do such a thing. It may seem that this invalidates the whole system, but I will try to explain why I believe that it does not.
Take the afforementioned epiphany as an example. If indeed this is an experience of the pure spirit (it may not be, though, but it still serves as a useful example). When you "come to your senses" after such an experience, you feel at a loss to explain the truth you feel you have grasped. I have stated in an earlier blog that I believe our thoughts to be the products of our physical brains and not our souls. Our brain operates logically (not necessarily in a strict, scientific sense), and our language even more so. Logic is dependent on categorizing, while the spiritual truth is a truth of the whole. Our logical brains can not fully comprehend the concepts of complete oneness or eternity, and our logical language can not explain them, for language is dependent on duality for its operation. Thus, the absolute truth can not be spoken, but words may lead you in the right direction, and it is on this higher level that the method must be utilized; as an overall judge of your complete body of knowledge rather than at the level of individual claims.
(To be continued...)