OK, look - from a formal logical point of view the belief that the universe is ordered is of the same value as the belief that God exists.
WE INFER - from our observations that the universe proceeds in an orderly fashion under the governing principle of cause and effect - this is the "governing assumption".
BECAUSE - the universe proceeds according to cause and effect you can investigate it using scientific experiments.
HOWEVER - because cause and effect is the governing assumption you cannot actually prove that what we are observing is a causal relationship and not merely a correlative one.
BECAUSE - if cause and effect did not operate you could not construct any experiments.
Now, this has all sorts of reprecussions - it's the same as with Newtonian Physics, just because it appears to fit the facts doesn't mean it does. That applies to the entire body of scienfic knowledge, including the "governing assumption".
Just because the body of Natural Philosophy known as "Science" has become so incredibly complex does not prove it to be correct any more than the massive complexity and elegence of Roman Catholic theology proves the Pope is God's Vicar on Earth.
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