Some basic questions I ask to determine a person's precommitments are:
"Do you believe that absolute truth exists?"Some questions we all ask ourselves are:
"What is your view of reality?"
"Do you believe that people can have certain knowledge of any proposition?"
"What is the nature and scope of reality?A problem that some philosophers have been reluctant to admit is that to ground any statement, proposition, or argument, we answer the above questions with an already assumed criterion for determining the scope and nature of reality and the scope and limits of what we can know. Again, everybody begins with metaphysical assumptions about the world that inform their epistemology. R. M. Chisholm had the courage to admit such, even though most philosophers in his day were wont to do so,
"What do we know?"
"What do we have a justification or warrant for believing?"
"How do we decide whether whether a proposition, p, is justifiably believed and true?"
"What will count as justification for believing some proposition, p?"
"What means do we utilize to determine whether p accurately represents reality?"
What few philosophers have had the courage to recognize is this: we can deal with the problem only by begging the question. It seems to me that, if we do recognize this fact, as we should, then it is unseemly for us to try to pretend that it isn't so. [R. M. Chisholm, The Problem of the Criterion, 37 as quoted in Greg L. Bahnsen, Presuppositional Apologetics: Stated and Defended, (Powder Springs, GA & Nacogdoches, TX: American Vision & Covenant Media, 2008), 84.]This brings us to a meaty philosophical issue: Since we, as finite creatures determine our own criterion to answer the above questions, how do we know that our starting assumptions about reality actually correspond to reality? That's what Chisholm defined as "the problem of the criterion", and it demonstrates the absolute interdependence of one's epistemology upon one's metaphysic. The two inform the other and are interdependent upon one another, and there is simply no way around this. This problem has lead to the many debates and disagreements in the world of secular philosophy and there appears to be no solution on the horizon; at least not a secular one.
Bahnsen rightly noted,
Common epistemological ground between disputants of different metaphysical positions cannot in principle be found, for answers to the questions of epistemology assume answers to the questions of metaphysics. [Bahnsen, 84. Italics his.]And so, given what we've considered thus far, the really meaty philosophical issues are these: If humans are left to choose their own criterion because metaphysics and epistemology are circularly interdependent, (a) how do we avoid utter subjectivism in doing so and worse, (b) how do we avoid utter skepticism as to what we can truly know since our ultimate assumptions about reality are not subject to external or empirical verification?
Starting with the Triune Starter
To avoid a subjectivist guessing game and/or utter skepticism, we must appeal to an ultimate locus of authority that is comprehensive in knowledge. This is what Christians call the Triune God, and I proclaim to you in Pauline fashion (Acts 17:23) that He is the only actual Criterion that humans can appeal to in order to justify knowledge. However, according to Scripture, while all men have some knowledge of the divine Criterion (Romans 1:18-32; 10:9ff), apart from regeneration, men will not submit to Him as the necessary grounding for their metaphysic and epistemology although they will necessarily assume things about the world that they can't otherwise account for on their secular program. Their failure to submit is rooted in hard hearts that are at enmity with their Creator and as such, they are darkened in their minds, their thoughts are futile (Ephesians 4:17-18), and they go about as Strato of Lampsacus, answering the world's questions using the world's principles, contra Colossians 2:3-8. Thus, this is not an intellectual problem, it is a moral problem that manifests itself in intellectual outward symptoms.
In conclusion, God's revelation of Himself in the 66 books of the Bible is the only valid escape from the skepticism that would otherwise logically result from the necessary, interdependence of metaphysics with epistemology. God's revelation of Himself in Scripture provides not only ultimate epistemic grounding, but also gives the necessary metaphysical content for the foundation of all of man's intellectual and spiritual pursuits. A Christian's apologetical presentation will be circular too since we have God and His revelation as our ultimate Criterion. However, what a Christian knows and how he knows it are both tied up with God's revelation and since God is infallible and comprehensive as to His knowledge, we can be certain that we have a "more sure word of prophecy" than that of worldly philosophy (2 Peter 1:19-21).