So why is it important to establish what is relevant?
Simply put, if one aims to pursue truth, one must therefor be constrained to look at that which is relevant, as they cannot find the truth of that which is not relevant.
This means that theology cannot be considered a path to truth. For example, lets take the idea of whether or not a god exists. As is currently defined by every religion I am aware of, gods cannot be found through human effort to observe them (not in a way that I feel is conclusive at any rate). That isn't to say that they cannot be observed under any circumstances mind you. But if we cannot observe them without change from outside our ability to influence, the existence of such a god is not relevant to our existence in its current form. Despite the fact that we could observe a god that descended from the heavens to proclaim its existence, until it decides to do so, we must consider it irrelevant.
So theists might at this point interject that I might have a soul, and thus the existence of such a god might be extremely relevant to the point where ignoring it might cause me eternal suffering. That's all well and good, but the idea of a god that punishes all who are not atheist to eternal suffering is just as valid. As we have absolutely no way of knowing which of these two (if either) scenarios exist, our reaction to their existence is blind. Therefor it is perfectly valid to simply assume that neither scenario exists, as any action you would take would be utterly disconnected to anything relevant.
When I said that the two gods are equally valid, I've stepped into a conclusion that can apply to anything that is not part of the relevant universe. As we have no way of knowing anything about anything not relevant, there is no reason to assume any one hypothetical is any more valid than any other. That is not to say they are equally likely however. It is more likely that a stone exists than it is that a blue stone exists. And following that, it is more likely that a blue stone exists than it is that a round blue stone exists. What this boils down to is that for all that is not relevant, it is safe to assume that nothing exists. This is not to claim that nothing exists that we cannot observe, just that there's no difference to us whether there is or not. As all non-relevant possibilities are equally valid, the most logical course of option is to live your existence as though the relevant universe is all that exists. You cannot gamble with this as that would be like gambling in a game you do not know the rules to, cannot see any part of, and do not know you're playing in the first place. Which is of course why Pascal's wager is so flawed.
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