One famous line in philosophy is "Cogito, ergo sum" which means "I think, therefore I am" from Rene Descartes related to the "mind-body problem" of philosophy and out of skepticism. He could doubt all external reality, but could not doubt his own existence, the internal source necessary to doubt all external reality. Now, this of course assumes an autonomy which does not exist, but it does demonstrates several things like the interpretation involved in external facts, and it brings to the forefront the "other minds problem" in philosophy. It is a perspective of pure relativism, that is helpful in so far as it brings out the need for contact with an external reality to indeed give justification and grounds for knowing external or objective that is reality outside of one's own existence. This is where being made in the image of God comes into play, such that our Creator has endowed us with an innate ability to be interpreters of reality, and our justification comes from the point of contact with the mind of God Himself. In this we are as it were, thinking God's thoughts after Him, for every true interpretive thought concerning reality. Of course the anthropological doctrine of being made in the image of God comes from the external Revelation from God in Scripture, it is how our Creator made us, to be dependent on Him, and so it is. All of this is to say that very very little can be proven 100% especially with regards to natural material reality. The only proofs that come to mind which are absurd and insane to deny, are immaterial conceptual reality, such as the laws of logic, mathematics, and so on, which are necessary for language, and interpretation of external material reality. So it is what it is, and what it is, is a kind of Creator-creature dependency that is theonomous, however the fallen nature of creatures such as us lends towards hiding from God, which for the mind amounts to suppressing the truth, while the Heavens declare the glory of God.