Skeptics (relativistic atheists, agnostics, liberal theologian etc...) want us to believe that we need to suspend judgment concerning TRUTH. These skeptics further attempt to claim dilemmas, validity of arguments, variance of opinion, and the relativity of thought (etcetera...), will lead us to the conclusion that truth (in general) is unknowable; that the "wise man: will simply withhold belief (as we are told by these skeptics). As commendable as this view may sound in many cases, it cannot be consistently applied to the majority of truth claims. Complete skepticism itself is self-defeating. The very declaration that "all truth is unknowable"is itself presented as a truth confirmation.
But, the truth statement purporting that no "truth statements can be made" undercuts itself (i.e. is "Self Defeating"). If this is not a truth statement OR if this is not a universal truth statement, then it is not even in the philosophical arena.
Stated succinctly: this claim of the skeptic/atheist and agnostic (etc...) that "truth is unknowable" is either:
1) a universal truth claim,
2) a particular truth claim, or...
3) neither a "universal" nor a "particular" truth claim.
First - If it is a universal truth claim, then it defeats itself (is self-stultifying); for it is claiming that no true statements (including that truth claim itself) can be made.
Second - If it is offered only as a particular truth claim, namely, that some (many, most, etc...) truths cannot be known, then it is self-consistent. However, in this case it does not eliminate the possibility that someone can know or establish the truth of some other world view. And if the question of the truth of these views is important or momentous to another person, then it would be a kind of defeatism, if not a cruelty, to dissuade him/her from attempting to discover what seemed so significant to his/her life and thought. Therefore it is "particularly" self-defeating.
Finally - If the skeptic claims he is making no truth claim at all, with his recommendation to suspend judgment about "all truth claims", then he must explain how a statement about whether truth is knowable can avoid being (itself) a truth statement/claim. In other words, when the skeptic states emphatically that the "Truth cannot be known!" he is begging the question(s): "Is that true?" And Then how do you know that?
So, why does the so-called skeptic not see the fallaciousness of their own world-view? Why could not the skeptic be "skeptical about all skeptical statements" without himself being a skeptic? Or, how can the skeptics claim sanctuary in alleged meta-truth statements about what is knowable in the realm of truth?
The problem with skepticism is this: Skepticism as defined is "the philosophy that holds that true knowledge is not possible". But Philosophy defined is "The branch of knowledge or academic study devoted to the systematic examination of basic concepts such as truth, existence, reality, causality, and freedom". So when we dig a little deeper, we find that the very claim that the premise of skepticism ("all truth is unknowable") is not a truth claim would automatically disqualify it philosophically; for philosophy is concerned with TRUTH and REALITY. To allow meta-truth or non-truth statements to dictate whether or not one can know truth is as un-philosophical as one can get. So if the skeptic maintains that his claim is a truth statement, then itself is SELF-DEFEATING (if universal) or UNSUCCESSFUL (if limited). Otherwise it is not a truth claim; in which case it is not even philosophical, that is, it has nothing to do with TRUTH and REALITY.
The claim of the skeptic (relativistic atheists, agnostics, liberal theologian) that skepticism is merely a non-truth proposal about the question of truth, which one finds most fruitful and usable for whatever theoretical or practical reasons will fail in its self-defeatism!
First, the assertion of the skeptic does not eliminate contrary positions. Someone (a solipsist for example)may ALSO conclude that dogmatism is right for the same reasons, claim victory, and win the debate.
Second, the assertion of the skeptic implies a consistency or pragmatic test for the truth of skepticism and opens it to all the criticisms of these positions, and the fallacies they contain.
Furthermore, especially the pragmatic test for the skeptical proposal is double-edged and it boomerangs. Skepticism may not work for most in the long run, and total skepticism fails totally. As Hume himself confessed, one of the most persistent arguments against skepticism is that even the skeptic cannot live it completely and consistently. Hence, skepticism cannot be established pragmatically.
And even if the allegedly non-truth proposal of skepticism were not defeated pragmatically, it is still self-defeating. No statement about all truth can disavow all truth implications, and the skeptical proposal is a statement about all truth.
Even working presuppositions about truth must be cognitive and meaningful. And whatever is meaningful must be subject to truth or falsity via the law of noncontradiction, for apart from noncontradiction we cannot even know what the statement means. But if the skeptical proposal is subject to the truth test of noncontradiction, it cannot avoid being offered as a truth statement. In short, to disclaim the possibility of knowing any truth is indeed a truth claim of the highest and most serious kind.
Truth cannot be denied unless some truth is being affirmed.