What is truth? Even if the Enlightenment assertion that reason leads to truth is correct, this theory is useless unless the premises reason employs can themselves be verified. But how can any human being driven fundamentally by a rationality that seeks to ensure survival and to justify pleasure rather than to discover truth hope to lay hold of such absolute knowledge of reality? Our senses clearly are not sufficient; individual sensory experience frequently varies from one person to the next, resulting in innumerable “facts” that may be true, but only subjectively so, reliant for their truthfulness on the imperfect minds that hold them. Reason is not entirely neutralized by subjective premises—but as its postulates are, so also will be its conclusions. Even proper syllogisms necessarily produce falsehood if they employ false presuppositions. Thus, reason must rely upon the superrational to procure objective truth.
Literally, a subjective truth is any truth that relies upon something else—a corresponding state of affairs in the physical or metaphysical world—for its veracity. In a sense, then, this universe does not provide a basis for any ultimately objectively true facts. While the universe itself and every planet, human, and quark within it (presumably) exists objectively at a given moment, any of these things, from the smallest particle to the entire universe, quite conceivably might not have existed and might not exist the next moment. Only an entity that cannot not exist can provide the basis for an unshakable truth—or, more succinctly, as St. Augustine long ago formulated, truth cannot exist objectively unless an unchanging God exists to uphold it.
Yet here is an awesome theological paradox. If God is who He claims to be—“I am who I am” (Exodus 3:14), “the same yesterday and today and forever” (Hebrews 13:8 ESV), the great Creator who does not change His mind (Numbers 23:19) in Whose necessary existence our contingent existence is wrapped up—if this is true, then our existence, thanks to His unchangeable character, is as unshakable as His. Being good Himself, God wonderfully saw fit to create the universe He deemed similarly “very good” (Genesis 1:31) in such a way that its existence would be inextricable from His and, incredibly, His existence inextricable from ours.
What, then, is truth? Truth is the facts about the world that is in an astounding sense as objectively real as the God who created it, and, of course, the facts (barely conceivable to the human mind though they be) of that God Himself. Furthermore, these facts are gathered by the senses and reason with which God equipped humanity to leave His children “without excuse” (Romans 1:20) for denying their knowledge of His existence. Ultimately, reason proves to be integral to the eyes of faith that are more trustworthy than the eyes of flesh because, unlike our physical senses alone, reason can direct us to the great Truth that upholds our own existence.