I have placed numerous quotations as a Survey of Philosophy by writers and philosophers over three millennia who have made statements that either define partially or more fully, directly or tangentially, what is philosophy or its characteristics. Here, I use those thoughts as background for my pursuit of a definition of philosophy.

From my reading of various texts of philosophy and online, it is reasonable to conclude that philosophy has four branches: metaphysics (cosmology), epistemology, logic (formal and informal reasoning), and ethics (value, esthetics). This particular designation comes from Titus et al. See References.

These branches are interdependent. One’s metaphysics will affect one’s epistemology. One’s epistemology will affect one’s ethics. As one develops and practices ethics, this activity may challenge both one’s epistemology and one’s metaphysics. Ideas or principles from one branch may cause a change in thinking in other branches.

Also, philosophical inquiry usually begins with one of these branches. A young person may wonder about his career (an ethical decision) and then begin to consider, “What is the meaning of life, anyway (value)?” An astrologist, grounded in materialism (metaphysics), may begin to wonder, “How does anyone determine what I ought (ethics) to do from what is?” Ludwig Wittgenstein, as an atheist (metaphysics), began to examine words and language and doubted that he could know anything for sure (epistemology).

The Issue of Truth Reflects This Interdependence

Two of the traditional tests of truth are coherence and correspondence. By definition, these words demonstrate that all the branches of philosophy are interdependent. One’s ethics must be correspond or cohere with one’s epistemology. One’s metaphysics must cohere or correspond with the surety of one’s knowledge (epistemology). Henry Stob in his definition of ethics demonstrates this interrelatedness.

Ethics deals with the voluntary conduct of individual man insofar as it is judged to be good or bad in reference to a single, inclusive, and determinative principle of moral value grounded in and validated by ultimate reality. (Stob, Reflections… page 24)

By now, the reader may have noticed that I have not included logic in this interdependency. Logic stands mostly beyond this interaction, at least in the process of logic and its rules.

So, (1) Metaphysics, epistemology, and ethics are interdependent. The degree to which one will affect the other varies among philosophers and their systems, but they can never exist independent of each other. (2) Logic is relatively independent of the other branches. (I say “relatively” because I am not sure of all the implications of that statement.)

What is it That Philosophers do? Methods

There is no one philosophic method. Different philosophers at different junctures of history have developed the procedure which seemed most promising in view of their own purposes and of the current methods in other disciplines. The Socratic dialectic differs markedly from the Aristotelian syllogism, the Cartesian deduction, and the Hegelian dialectic. Contemporary phenomenology and analysis are different again. Yet each method reflects a philosophical viewpoint, a larger epistemology and even metaphysical presuppositions. (Arthur F. Homes in Nash, The Philosophy of Gordon Clark, 1968, page 202)

I think that we can safely say that philosophy is a quest for truth. Certainly, truth encompasses metaphysics, epistemology, and ethics. Truth is the serious philosopher’s hope and dream. “Philosophical inquiry centers on a quest for truth about crucial issues that are perennially discussed by thoughtful men.” (Geisler, Introduction to Philosophy, page 19) And, perhaps we can agree on a definition of truth as “what is” or Reality. (I capitalize “Reality” because God is the Ultimate Reality. (I will discuss this idea in more detail at a later time.) So, philosophy is a quest for truth or Reality.

Arthur Holmes (above) has named a number of methods of philosophy. But the reader should note that these are not methods only. The Socratic dialectic would find truth in a sort of synthesis of minds. The Aristotelian syllogism takes propositions and reasons logically from them. Cartesian deduction posits the proposition, “I think; therefore I am.“ Thus, truth or knowledge is grounded in the person reasoning or in Descartes himself. The Hegelian dialectic assumes that truth is found in a synthesis of two opposite propositions. So, methods themselves are interdependent upon a metaphysic and an epistemology. They assume propositions of truth and reason from them.

The Law of Non-Contradiction

While all philosophers may not agree with the law of non-contradiction, it is widely accepted among them. And, one can forcefully argue that communication and rational thinking is impossible without this law.

Reality poses a dilemma. “There are no absolutes.” “Truth does not exist.” Each statement (proposition) contradicts itself! “There are no absolutes” is an absolute. “Truth does not exist” has no meaning if the opposite is not true. This situation is not complicated. Very simply, if communication by language is not possible, everyone should just shut up and be quiet. For Wittgenstein to deny the possibility of language to communicate, he had to use that dastardly method of language itself!

We gain considerable insight into philosophy and philosophers here.

(1) Language Does Communicate

I have been married to my wife for more than 40 years. We have communicated fairly well (not perfectly). The newspaper arrives every morning on my driveway. It communicates (not perfectly) news from around the world. The Chairman of the Federal Reserve Board of the United States holds a news conference and millions of investors around the world make decisions based upon what he communicates! Now, such communication is not perfect, but it works to great degree of accuracy. So, in our pursuit of philosophy, let’s apply some reality that we all understand.

(2) The Law of Non-contradiction is Mandated by Language Itself

Not only is it obvious that two opposites cannot be true at the same time, but certain constructs of language (propositions above) mandate that this law is true. For example, a cat is not a dog, and a dog is not a cat. I am not you, and you are not me. A star is not a planet, and a planet is not a star.

Enter the Bible and Jesus

We did not start our reasoning with God except for a brief mention concerning Reality. But, based upon what we have discussed so far, Jesus enters the scene. “I am the way, the truth, and the life. No man comes to the father but by me” (John 14:6). Jesus has claimed an all encompassing philosophy; He has claimed to be truth! (Not only that but He has added a new dimension # the need of salvation (being with the Father)!

Based Upon the Law of Non-Contradiction, Jesus’ Claim to Truth Must be True or False

There are no other options. Many people could just reject the historical accuracy of this statement. But, there is another problem here. (1) We have determined that truth exists; not what truth, only that it does exist somewhere by the law of non-contradiction. So, Jesus, claim is at least plausible on this basis. (2) To deny His claim, we would have to deny that history of His time period is impossible to know because Jesus’ life, death, burial, and resurrection are (far and away) the best documented facts of the first century A.D.. So, to deny this claim of Jesus, we have denied the possibility of history for that period, but most time periods of history (the evidence of writers and witnesses). We have upset the basis upon which history is determined. So, a denial of His claim has repercussions far beyond the “religious” sphere.

(3) We would have to deny the experience of millions of Christians since the First Advent. Oh, you say, that is easy. Not so fast. Pragmatism is one of the traditional tests of truth. These Christians would testify to the “pragmatic value” of salvation in Christ and of his commandments to love God and man. Also, empiricism one of the major forms of epistemology. So, to deny the claims of Jesus, one has to throw out the possibility that what Jesus said was true, the historical method, one test of truth, and one theory of epistemology.

Why This Digression Into the Claims of Christianity?

What does Christianity have to do with trying to define philosophy? Surely philosophy can be defined without a discussion or reference to Christianity!

Actually, a definition of philosophy is not possible without a discussion of Biblical truth for this reason: the Bible makes a truth-claim that forces one to choose between that truth and all other claims.

The Bible makes many claims to be Truth. Chapters and books have been written on this subject, so an exploration into all those claims is not necessary here. I will simply state that Jesus’ use of the Old Testament verified it as truth and that the New Testament claims truth for itself (for example, II Timothy 3:16-17 and Revelation 22:18-19).

So, the law of non-contradiction divides truth into either Biblical Christianity or a non-Biblical reality. By coherence, the Bible itself divides the world with such designations as, light and darkness (as truth and error, not physical light and its absence), sheep (true Christians) and goats (pagans), believers (in Christ and the Bible) and unbelievers (in non-Biblical claims), and Biblical truth vs. the world (people as a group), the flesh (the sinful nature), and the Devil (the personification of everything that is against God).

We digressed into Christianity because the Bible (God) forces philosophy, as a search for the truth, into two unavoidable categories: Biblical Christianity and every other philosophy.

Then, if only these two categories exist, then all religions of the world fall into the second category. All other metaphysical claims (cosmologies) fall into that category. And, by interdependency, all epistemologies and ethics fall into this second category.

So, our definition of philosophy is the pursuit of truth within (1) Biblical Christianity or (2) non-biblical religions and philosophies.

Attention! Both Christians and Non-Christians


A denial of the truths of the Apostles’ Creed is not a simple matter. You must overthrow commonly accepted methods of scholarship in history and philosophy. If you throw in Pascal’s Wager, you have some serious thinking to do.


This article was really written for Christians, philosopher and non-philosopher alike, especially those who are incoherent, non-corresponding, and illogical about Biblical truth. But, I had to begin with a more or less “secular” approach. Even philosophers who are Christians are often assert philosophical “truths” before they assert Christian (Biblical) truth.

I can hear the reaction, “If philosophy is defined in this way, then philosophy becomes theology.” Well, yes and no. No, emphases and areas of interest will vary. Yes, philosophy cannot proceed except under a thoroughgoing Biblical authority. John Frame writes.

It is difficult for me to draw any sharp distinction between a Christian theology and a Christian philosophy. Philosophy generally is understood as an attempt to understand the world in it broadest, most general features. It includes metaphysics, or ontology (the study of being, of what “is”), epistemology (the study of knowing), and the theory of values (ethics, esthetics, etc.). (Ed: Frame left out logic.) If one seeks to develop a truly Christian philosophy, he will certainly be doing so under the authority of Scripture and thus will be applying Scripture to philosophical questions. As such, he would be doing theology, according to our definition. Christian philosophy, then, is a subdivision of theology. Furthermore, since philosophy is concerned with reality in a broad, comprehensive sense, it may well take it as its task to ‘apply the Word of God to all areas of life.’ That definition makes philosophy identical with, not a subdivision of, theology. (Frame, knowledge of God, page 85)

Cornelius Van Til says similarly.

Christian apologetics (philosophy) must concentrate on the central concepts of the Christian life and world view as a whole. It will stress rather the unity that the discreteness of a truly Christian theology and a truly Christian philosophy. It will make use of the main concepts of a true Christian theology and a true Christian philosophy, combining them for its own purposes.

Interdependency, Coherency, and Correspondence

A huge debate exists among Christians between presuppositionalism and evidentialism. While this debate primarily concerns apologetics, it has a specific application here to philosophy. At some point, I will enter that debate. For now, I simply posit for you to begin anywhere that you like. I believe that presuppositionalism is true because even evidentialists have to begin somewhere, even if they begin with empiricism being true or epistemologically sound. The point that I want to make here does not really concern either view. What I want to do is go back to interdependency of epistemology, metaphysics, and ethics.

At some point in their reflection, a person interested in Christianity will begin to evaluate the Bible at some level. Is it truth? How was the canon formed? Is the God of the Old Testament different from the God of the New Testament? Should the Apocrypha of Roman Catholicism be part of the Bible? May I steal from my neighbor when his food will save my starving family? What is a just war? Etc, etc.

There is a movement in thinking from metaphysics to epistemology to ethics, back and forth, among all three. Some ethics may challenge whether the epistemology of the Bible. For example, if my teenage daughter is illegitimately pregnant, and if God is love, why cannot she get an abortion? Or, science gives strong arguments for long periods of time when the Bible limits the same period to days or hundred of years; how can I reconcile the two different explanations?

At some point in this movement, the question should be confronted concerning the canon and the inerrancy and sufficiency of Scripture. That is, what books of the Bible should be considered the “very Word of God written?” And, if they are God‘s words, are they accurately delivered to me today so that I can trust my life, liberty, property, and future eternity to them?

I want to explore all these issues and more in greater detail. Suffice it here that I would like to apply the principles of philosophy that we have already reviewed. Correspondence, coherence (consistency), the law of non-contradiction, and the interdependency of epistemology, metaphysics, and ethics demand that the 66 books of the Protestant Bible stand against all other epistemologies, metaphysics, and ethics.

Back to Logic and Theology

John Frame goes on to say:

If there are any differences between the Christian theologian and the Christian philosopher, they would probably be (1) that the Christian philosopher spends more time studying natural revelation than the theologian, and the theologian spends more time studying Scripture, and (2) that the theologian seeks a formulation that is an application of Scripture and thus absolutely authoritative. His goal is a formulation before which he can utter, “Thus saith the Lord.” A Christian philosopher, however, may have a more modest goal–a wise human judgment that accords with what Scripture teaches, though it is not necessarily warranted by Scripture.

A Christian philosopher can be of great value in helping us to articulate in detail the biblical world view…. to interpret Scripture; philosophers often have interesting insights about language, for example. (Doctrine of the Knowledge…, pages 85-86)

And, I would add, philosophy is central to the role of apologetics, the defense of the faith.

But, Frame also addresses my concern which is one of the primary purposes of this website.

We must beware, however, of “philosophical imperialism.” The comprehensiveness of philosophy has often led philosophers to seek to rule over all other disciplines, even over theology, over God’s Word. Even philosophers attempting to construct a Christian philosophy have been guilty of this, and some have even insisted that Scripture itself cannot be understood properly unless it is read in a way prescribed by the philosopher! … But the line must be drawn: where a philosophical scheme contradicts Scripture or where it seeks to inhibit the freedom of exegesis without Scriptural warrant, it must be rejected.”

I contend that many philosophers who are Christians have transgressed in the way that Frame has named. On the one hand, this transgression is only consistent. Where one spends most of his time reading, thinking, writing, and speaking will strongly influence his thinking elsewhere.

In Christianity on the other hand, this transgression is dangerous. (1) The thinking of men (philosophy) becomes authoritative over Scripture. In my writings over 30 years, I have given numerous examples in medicine and psychology, two fields which I have studied extensively. (2) The Christian’s life is weakened because he is not following “the way, the truth, and the life.” (3) Christians’ influence in the Public Square is weakened because God will not honor man’s thinking, and He will not honor other gods. (4) The glory of God among men is diminished because the people bearing his name, Christians (Christ one’s) have exchanged the truth of God for a lie.

Strong accusations. But, over time I hope to give many concrete examples on this website I have given hundreds of examples in medicine, psychology, and other areas of worldview over nearly four decades. For laymen, I hope to write a book that will give simplify philosophy without compromising either the benefits of philosophy or the truths of Scripture.

Quo Vadis, Christian Philosopher?

I do not Want to Diminish the Benefits of Philosophy

Philosophical inquiry and history makes the faith in our God and His Bible a more solid foundation or “rational.” The greatest philosopher who ever lived was Jesus Christ. Next could be argued are the Apostle Paul and Augustine of Hippo. As I will fault Christian philosophers on this site, I will also show how the best of philosophy strengthens our faith and worship.

For example, coherence is a challenge for our theology and our ethics. What is right for an individual must be right for the family, for society, for the church, for the nation, and for the world without conflict. God is One and He has One Plan.

We must show that the truth of the Bible corresponds completely to the universe. Science and the Bible speak two different languages. Every attempt must be made to resolve apparent conflicts. Understanding and critique of language is a legitimate tool of philosophy.

What could be more pragmatic than Biblical ethics? First, there is the effect at the personal, social, and political level. But, there is also an effect at the physical level. In the Old Testament, prosperity and crop production were linked to the ethics and worship of the people. And, creation groans for its own redemption (Romans 8:18-22). If Biblical Christianity is true, then it can only be a thoroughgoing pragmatic system.

Then, there is apologetics. For the past four decades, Christians in philosophy have argued tit for tat with pagan philosophers. Some of the latter have come to faith in association with the argument of the former. Many philosophers throughout history have tried to find peace and meaning in their work. No philosophy will ever provide that, as only regeneration and Biblical obedience can accomplish those ends. While the Christian philosopher should show grace (more accurate than “love” which Christians commonly use) towards unbelieving philosophers, they dare not let them rest in their false reasonings.

And, perhaps the best is mentioned last. Remember the four branches of philosophy? What have we left out? Logic. Logic. Ah! How many issues could Christians resolve if they learned to reason more carefully in Bible understanding, theology, ethics, and apologetics? We have the true propositions of Scripture. We only need to reason logically from them.


So, I am not diminishing philosophy at all. In fact, I am arguing for a more thorough application of it. But, the Scriptures as God’s Word Written cannot be compromised for the reasons name above. Perhaps, God will honor this website to His glory and the greater understanding and good of Christians and the world.


I started out in this article to show that “philosophy,” as such, does not exist. There is so much conflict of ideas and difference in methodologies among philosophers for the past three millennia that any claim by any one of them to be true is preposterous. Therefore, philosophy is just an exercise in one man’s or a group’s opinions about what might be true. Philosophy is also a way for a thinker to avoid God. He can indulge himself in complicated systems, old or new, and never have to face the issue of God and His Revelation.

But, the tools of logic itself drove me to conclude that “philosophy is a quest for truth.” The law of non-contradiction about the statement, “No truth exists,” mandates that there is at least one form of truth. Then, the law of non-contradiction applies to Jesus’ statement, “I am the truth,” in that it forces a necessary conflict between His claim and all other claims to truth, whether religious or philosophical.

The following quote was found several months after I wrote the above:

Thus we can see that logical implication is not a religiously neutral something. It is dependent on ethical values, which are ultimately religious values. Logical necessity can be understood as a form of ethical necessity, which is ultimately a religious necessity. Logic, therefore, can be viewed as a brand of ethics. But the only true ethical values are those revealed to us by God. Therefore, logic presupposes Christianity. (John Frame, The Doctrine of the Knowledge of God, page 248.)