I. INTRODUCTION 

Epistemology is closely related to Ontology. Whereas Epistemology asks questions about the origins and validity of knowledge, Ontology asks questions about the nature and origin of being. Both philosophical disciplines attempt to address and study these basic issues regarding life on earth: “Why do I exist and what should inform my beliefs?” 

The Christian answers those questions with the presupposition that Scripture is the final authority; the Bible informs his thinking regarding Epistemological and Ontological concerns. On the other hand, the secularist is informed by other sources. Our presuppositions—i.e., what we utilize to formulate our answers in relation to these two disciplines—are as multiple as they are variant. For instance, many people habitually rely on the values they learned in their upbringing to inform their thinking and decisions for today; they conscientiously or subconsciously rely on their upbringing as the final authority in the decisions they make in living their lives. Others rely on their current experiences and conditions, i.e., the presenting situation; still others are guided by the ideology of their teachers and professors who taught them, or the books they have read. 

Therefore, wise is the individual who can identify not only another’s presuppositions in life (think of a presupposition as an assumption made in advance) but his own! What informs his thinking? What determines his actions? 

To think through things with a curiosity and investigative quest and to understand their epistemological basis is to be both discerning and wise. 

What informs that belief or action? The wisdom to ask these questions and answer them accurately is critically important, especially where the future course of a nation is determined. To live and think with epistemological discernment is the sheer opposite of what the Book of Proverbs characterizes as a simpleton. Discipline yourself to be a deep and discerning thinker! 

II. CONTRASTING VALID AND INVALID PRESUPPOSITIONS 

The growing Christian is conscientiously putting off and putting on. He is leaving behind invalid and limited epistemological presuppositions and in their place he is reprogramming worldly thinking with a biblical epistemology. Note this in Ephesians 4:22–25: 

“… in reference to your former manner of life, you lay aside the old self, which is being corrupted in accordance with the lusts of deceit, and that you be renewed in the spirit of your mind, and put on the new self, which in the likeness of God has been created in righteousness and holiness of the truth. Therefore, laying aside falsehood, speak truth each one of you.…” 

This internal growth process is synonymous with what Paul tells the otherwise worldly believers in Corinth. In 2 Corinthians 10:5 the Apostle states: 

“We are destroying speculations and every lofty thing raised up against the knowledge of God, and we are taking every thought captive to the obedience of Christ.…” 

This passage is in the same context of Paul’s earlier pronouncements regarding the fallacy of human reasoning apart from divine revelation (cf. 1 Corinthians 1:18–25; and Job 5:13, Psalm 94:11). The word speculations carries with it the idea of the world’s ways of reasoning, its philosophies and its false religions. All of these bombardments are attempts by the evil one to shelter the seeker of truth from the witness of his conscience and the ever-beaconing call of the Gospel of Christ. In summary, it is normative behavior, and the full-on expectation of God that His called-out representatives hone in exclusively on a biblical epistemology, forsaking all other presuppositions of truth. Every way of thinking must be brought captive to the obedience of Christ. 

A. THE ROLE OF FAITH IN PRESUPPOSITIONS 

It is by faith that all hold authoritative their beginning points of reasoning—or presuppositions regarding what is right and wrong. In respect to the aforementioned, one assumes by faith the correctness and authority of his parental, experiential, professorial, authorial, or revelational epistemology. This is an important distinction to make up front because in the illustrations that follow, non-believers will often state (in a game of one-upmanship) that the faith-based beginning point of Christians is not the case with them. 

B. TRUTH FROM THE INSIDE 

Now let’s go a step further. Two additional epistemological starting points that may be a bit more difficult to understand are called Rationalism and Empiricism. Rationalism begins with reasoning—internally reasoning outwardly from the human mind by the use of deduction and logic. Empiricism calls on man’s senses to gather knowledge and information which in turn is processed in the human mind and is utilized as the basis for determining what is right and wrong. What they have in common is the assumption (by faith, I might add) that the human mind— all by itself—can be relied upon to discern truth from falsehood. This is a huge presupposition! In contradistinction, the Christian believes: 

The origin of truth is outside of the human mind. It is found in God’s revelation to man: The Bible. 

The presupposition of the believer is that the human mind is biased toward sin and given to irrationality and partiality due to the fall of man in Genesis 3. In that the fall impaired man’s abilities to think truthfully at all times (theologically this is called the noetic effect of sin), the human mind is not a trustworthy source of certitude. To hold to an epistemology that assumes right and wrong, that moral truth can be determined by the use of one’s sensory perceptions, is to work in a contaminated laboratory. The Bible says we cannot trust ourselves to come up with the right answers. In other words, absolute truth, what is right and what is wrong, cannot be derived consistently and accurately from a secular humanist epistemology. In fact, the closer the matter being reasoned out is related to moral truth, the more biased the fallen human mind becomes. 

C. TRUTH FROM THE OUTSIDE 

The testimony of Scripture is this: truth must be derived from an external epistemological source untainted by fallen and defective human reasoning. The fallen sin nature of man is the reason why God had to reveal Himself to man outside of man. Both Jesus Christ and the Scriptures are testimony to that. God has revealed His plan to us not only through His incarnate Son, but through the external, objective written source that is untainted by sin called the Bible. In this way He purely communicates the message of redemption and objectively conveys truth throughout the course of time. 

It follows then that the degree in which man studies God’s revelation is the degree to which he possesses the certitude of truth, right thinking, and a proper ontological understanding of life’s purpose. 

Rejected by the unregenerate, and embraced by the believer, the Bible is the only reliable and certain epistemology in the universe; all other sources are tainted to some degree by the bias of endemic sin. Furthermore, to differ with this evaluation is to exalt one’s opinions over and above the authoritative teachings of the Bible. Of course, self-authority is the popular trend, and one does not have to look very far to see it playing out in American culture. 

One example of secularists’ epistemological hubris is the ardent reaction to Dan Cathy’s (Chick-fil-A) statement regarding God’s definition of marriage as being between a man and a woman. 

Secularists loudly assert that their latest cause du jour is morally superior to biblical authority, saying in essence, “We have a better understanding of marriage than God does.” The problem is this: Unbelievers whose reasoning flies in the face of divine revelation confront the daunting task of proving their beliefs have a stronger, more reliable basis than the Word of God. What authority or basis, what is the presupposition that informs their opinion? Is it not subjective 

D. TRUTH PERSONIFIED 

We have seen that truth comes from an external, untainted source: Notice what Jesus adds to this understanding in John 14:6: 

“I am the way, and the truth, and the life …” 

The Scriptures not only proclaim that the certitude of absolute, authoritative truth is outside of fallen man, but that Jesus, Himself, the second member of the Trinity, is the personification of truth. In other words, since one of the attributes of God is truth, one must accept God to know the truth; therefore to reject God is to reject truth. 

E. CIRCULAR REASONING 

Under the first point of this outline, I mentioned that starting points for any and all of man’s bases of authority are held by faith. That means that every epistemological argument is circular in nature. The fact that the Christian uses the Bible to uphold his premise—that the Bible is God’s Word—is no different than the evolutionist utilizing fossil evidence in an attempt to support his world view. Whereas the theory is informed by the source, the theory also informs the source. Why, then, should one understand the Christian’s epistemology to be superior? It is for this reason: 

In direct contrast to Christianity’s theistic intervention is humanistic invention. Whereas the former is imported from the outside, the latter is manufactured from within. This stark difference must be emphasized and underscored by the theistic defender (the Christian apologist). Put another way, by way of cogent argumentation, unbelievers need to realize the absurdity of their epistemology—theirs is a belief informed by internal estimation, whereas ours is a belief informed by external revelation. Christian epistemology is informed by the infallible mind of God, whereas Humanism is informed by the fallible mind of man. For this reason the believer’s by-faith starting point, his presupposition, is superior. In essence, it’s not all about me, it’s all about God. 

III. ILLUSTRATING VALID AND INVALID PRESUPPOSITIONS 

In order to create a better working understanding of the aforementioned, several narrative illustrations are in order. 

A. DONAHUE AND MOHLER 

Years ago Dr. Albert Mohler debated Phil Donahue on the latter’s television program. Dr. Mohler is the dean of a leading Evangelical seminary. Donahue pressed Mohler regarding the justice of a Nazi murdering a Jew, the Jew going to Hell and the Nazi’s remaining possession of the ability to possibly obtain Christian salvation. Rather than allow Donahue’s reasoning to place Mohler on the defensive, in my humble opinion Mohler should have challenged Donahue regarding his epistemological basis for his stated assumption that murder was wrong in the first place! What basis of authority did Donahue possess for assuming that murder was wrong in the formation of his question? The point being that Donahue borrowed from Mohler’s scriptural presuppositions in formulating his charge of theistic injustice (as though God were not fair—arrogantly implying that he was more fair-minded than the God of the Bible). Had I been in Mohler’s position (and without all the pressure of live TV), I would have said, “It’s obvious from your statement that you believe murder to be wrong. That is certainly my position, but what is your basis of authority to conclude that murder is wrong?” Donahue was clearly borrowing principles from Mohler’s playbook without attribution, while simultaneously discounting the veracity of the author of the Book! Donahue can’t have it both ways. Such hypocrisy should have been brought to the surface. 

Properly and lovingly interrogated, Donahue would have to state that he believed murder was wrong based on his own thinking. (The Humanist will typically attempt to counter this conclusion with “everyone thinks murder is wrong, therefore it is wrong,” which can be summarized as an argument from convention.) The problem with postulating an argument from convention is that not everyone believes murder is wrong: witness Saddam Hussein and, of course, Adolph Hitler—they both headed up conventions of people who thought similarly. So then what’s Donahue’s basis of authority other than self-opinion for thinking he is right? 

B. SUMMARIZING DONAHUE AND MOHLER 

Apart from the Scriptures, Donahue possessed no moral authority other than his personal opinion to wage his attack on Mohler. Mohler could have carried the day had he stated that Donahue’s morality was a matter of his own interpretation to begin with. Unless one borrows from the presupposition of Scripture’s teaching, i.e., in this case, “thou shall not kill,” one can only say that Hitler was wrong to murder the Jews based on a personal opinion. Conversely, the believer can authoritatively and congruently proclaim murder is wrong based upon an objective third party source outside of self that is applicable to all, not just one’s self. For the unbeliever to remain congruent he must say, “I believe murder to be wrong, but it may not be wrong to you, so I cannot tell you to not murder someone.” 

In summary of this illustration, developing and utilizing epistemological discernment will enable you to wage your battles further upstream where guns aren’t loaded and opponents are the least fortified and equipped to defend themselves. 

It’s not your word against mine: it’s your thinking versus God’s. 

The believer is said to be God’s ambassador (2 Corinthians 5:20). To the degree believers represent the Book, they speak with the authority of God. Apologist Greg Bahnsen summarizes leading Reformed apologist Van Til’s epistemological genius when he states, “[Unbelievers] face the challenge of justifying [their source of knowledge] with good reason.” (Van Til’s Apologetics Phillipsburg, New Jersey, P&R Publishing, 1998.) The unbeliever is his only source for concluding what is right and wrong and his opinions are thus devoid of any authority other than themselves and not enforceable on anyone outside of themselves. In fact many an epistemology “is informed by an ethical hostility toward God.” (Ibid., p.157.) When considering a bill in subcommittee or voting, take this into account. 

Is this bill or the candidate’s viewpoint rooted in Scriptural truth and principle—or is it based on what someone subjectively thinks is right or wrong? 

What is the underlying epistemology related to the presenting matter? That is the question! If you develop a smell for this, you will be wiser in the days and years ahead. 

IV. SUMMARY 

In subscribing to an epistemology based on outside revelation, I am always excited to get to the point in a discussion with a nonbeliever where I can ask the philosophical haymaker question, “So who should I believe— your opinion or that of the Bible?” This is the essence of epistemological authority. And then it is always good to lovingly and kindly follow up with the comment, “Something to think about, isn’t it?” 

The believer does the unbeliever a great service in helping him to clearly understand that his basis of authority is self and self only. It is this sobering exercise that can bring a person toward repentance from arrogant pride and lead him toward faith in Christ. Paul had this same thought in mind when he wrote to the Corinthian believers in 1 Corinthians 2:14: 

“But a natural man does not accept the things of the Spirit of God, for they are foolishness to him …” 

Why? In John 3:19, Jesus says: 

“‘… men loved the darkness rather than the Light, for their deeds were evil.’” 

Jesus goes on to say in the next verse that the reason unbelievers do not come to the light is that they do not want their sin to be exposed. Probing someone’s epistemology can, hopefully, help him begin to see the foolishness revealed by his lack of any objective basis for what he believes. Romans 1:22 states in this regard: 

“Professing to be wise, they became fools …” 

Humility is a necessary (God-given) first step in conversion to Christ, and effective apologetical argumentation can often serve to achieve those ends. Before some piece of legislation gets your support or some candidate gets your vote, will it or they face your challenge of their need to justify the source of their knowledge?