His opening chapter discusses the necessity of worldview for establishing any principles or practices of education. Worldview is an inescapable category, not because one's thought must be coherent (though we should strive for such an ideal), but because thought itself imposes its perspective upon whatever subject matter is directed at contemplating. I may decide I want to eat a burger and fries, but my decision is not made apart from underlying assumptions. Even if my decision is one of pure emotion (I'm so hungry!) it is the underlying beliefs that determine what significant factors will come to mind as I seek to fulfill the urge to satiate myself. Consciousness of worldview is not a necessary component of having a worldview anymore than coherence is a necessary component of worldview.
The assumption of these two factors (consciousness and coherence) lead many folks to reject the idea of worldview on the basis of its philosophical idealism (that is, ideas or the intellect underlies or determines action, rather than irrational or material forces). Yet even the thorough-going materialist has a worldview, for his explanations of experience are based upon the assumption that ideas do not determine human action, but rather chemical and biological reactions do. It is precisely on the basis of the inescapability of worldview that the Christian must be self-conscious of his or her own assumptions, and the implications that follow from them. The less coherent the worldview, the less Christian, for a fundamental assumption of the Christian worldview is that God is eternally omniscient, and therefore His thought thoroughly determines the knowledge of all things whatsoever. Thorough intellectual determinism implies coherence, or system, as Clark puts it.
Clark's second chapter outlines the Christian worldview on the basis of Scripture and in distinction with several outstanding alternatives offered throughout the history of philosophy. The main point of the chapter is to prove how pervasive worldview must be if it is to remain consistent and coherent with God's revelation. To poison the Christian worldview with external presuppositions is to undermine the sum of knowledge that constitutes the system of beliefs that God has given us to know, to contemplate, and to direct our lives upon. The third chapter further clarifies the necessity of a thorough Christian worldview by demonstrating the impossibility alternative worldviews face in explaining the most basic assumptions regarding knowledge (and therefore man, the world, God, and everything).
Chapter four provides what may be the most applicable chapter to the contemporary Christian culture in the United States: No neutrality can be found among worldviews. Superficially, worldviews may arrive at the same conclusions, but they can never arrive there by the same steps of reasoning. Though superficial thinkers may conclude that it is only the conclusion that matters, such a conclusion is not only hasty, but irreverent. If God demands all of our thoughts to be directed toward worship (Clark labors to demonstrate how pervasive "religious" activities are in the Scriptures) then not even the chains of reasoning we follow are quarantined from the commandments of God to love Him and love one another. Beside the commandments given by God, the unbeliever is no more able to maintain neutrality. By rejecting the God of Scripture, all of his knowledge is purposed upon something other than glorifying God.
Even the most basic instruction in arithmetic cannot escape this factor. It may be inconsequential whether an atheist or a devout Christian instructs a child that 2+2=4, but the application of such knowledge, as well as the labor of relating that knowledge to all other knowledge (for Christianity is a system of beliefs, not a disconnected mass of propositions and feelings) demonstrates how opposite is the instruction of each. To the objection that young children need not learn how to apply or relate arithmetic until some later age, we may reply that children enter the world no-less-like adults in their attempts to synthesize and explain the information they receive. Children are already, apart from any instruction, attempting to "put two and two together." This conclusion is necessarily implied by the doctrine of the imago Dei. Because God has made man a reasoning being, and because reasoning follows the laws of logic, and because the laws of logic reveal the systematic nature of knowledge, therefore all knowledge must interrelate. We may be marred by sin and reason mistakenly, but we no-less strive to integrate what knowledge is to be had.
After neutrality, Clark spends a chapter on ethics because it is prerequisite to the development of the practices of education. There is much philosophy in this chapter, which may lead the reader to wonder how exactly it relates to the subject of education. A key thought that helps to remember is that skepticism--the conclusion at which all non-Christian philosophies of necessity arrive--not only destroys our ability to know the truth, but therefore as well our ability to live according to the truth. Since education is not simply instruction of what is, but also of what may be done with what is, only the Christian worldview is adequate to make men holy as well as well-informed. Though humanism's overarching purpose is the improvement of man, its inherent skepticism ensures that it can never maintain that purpose in any definitive manner--all is groping in the dark, or as Scripture states it; the blind leading the blind. So while humanism may affirm the very same conclusions of Christianity, its underlying beliefs destroy all of its ability to accomplish such ends, all the while hating the very philosophy (Christianity) that can ever have success toward the improvement of humanity.
The best chapter in the book, in my opinion, is the sixth, where Clark outlines a Christian philosophy of education in general. He masterfully reduces heretical epistemologies to absurdity and affirms the necessity of intellectualism and the subscription to, use of, and glorifying nature of creeds. Many Christians in the present day are opposed to the intellect and therefore to creeds, because they have imbibed the Kantian doctrine of knowledge that was promulgated into religion by Schleiermacher. Kant believed that God was unknowable because human knowledge could only grasp the finite, temporal objects of knowledge, and because God is infinite and eternal, He is not even an object of knowledge to be known by men. Therefore, since God cannot be known, yet He is, He can be felt. Schleiermacher developed this notion of Kant into a thoroughgoing religion of sentiment. Later authors, such as Kierkegaard, were dissatisfied with intellectual and sentimental Christianity and therefore asserted the will as the primary means of worshipping God. One must do, and do sincerely, if one is to please God. But Clark demonstrates that one cannot do without first knowing something, nor can a feeling such as love be made superior to the feeling of hatred without knowledge, which is intellectual. Those who would wish to make all three equal (emotion, will, and intellect) have no basis upon which to decide whether to follow an emotion rather than suppress it; for all things being equal, none can be used to determine a decision.
Because the intellect directs the human being, the most natural form of expressing one's devotion to the truth is to intellectually reproduce it, summarize it, meditate upon it, and memorize it so as never to lose it or have it fall away from consciousness. Creeds are precisely this sort of worshipful engagement because they seek to make explicitly those truths which are both explicitly and implicitly given by God in His revelation to us. Clark points out the numerous Scriptural passages dealing with the relationship between knowledge, truth, and fellowship with God, but perhaps this one expresses the idea best:
Before the enjoyment or possession of the object, whether it be picture or God, there is desire, love, or volition; afterward there is enjoyment, possession, contemplation. The will is directed toward an end or aim that is future; possession present. Clearly the desire of an end is not the attainment of that end. Now the Scriptures make certain definite characterizations of the end of our endeavor. The Apostle John records the words of Christ in his High Priestly prayer: "This is eternal life, that they should know thee, the only true God". . . .The end is something we long for now; it is something we desire. When we come to this final state, we shall desire it to continue, we shall still love to see God face to face. But the act of desiring and the act of seeing are two conceptually distinct acts; the former is the means and the latter, the beatific vision is the end.
Seeing is a metaphor for understanding with our mind what is true, and the chief end of man is to glorify God, which implies a true knowledge of Him, unfettered and unveiled. Here is why the intellect is supreme, because it is God's purpose to be known and thereby glorified. What else then should any and all education be directed at than this chief end?
The last two chapters deal with two subsidiary matters (chapter 7) and an outlook on how Christian education might proceed in practice (chapter 8). There are a few helpful applications to be gleaned here, but which I will refrain from commenting upon in detail. One note of importance for contemporary readers is that Clark sees both the family and the Church as responsible for the education of children, and therefore accepts as valid both family cooperative (parochial) schools as well as church incorporated Christian schools. The practical costs and benefits of either are circumstantial, but both--unlike public schools run by the State--are commanded and sanctioned by Scripture.
It should be evident to all reading this post, and even more so those reading Clark's book, that State-run public education is inherently anti-Christian--even in a Christian State. The tendency of State-run education is to inculcate its own doctrines into the minds of its pupils (Roman Catholicism is explicit in this regard) and a secular State is no less inclined by necessity to this end than is a religious State. Education is the province of the family and the Church, and though the State is duty-bound to protect the rights of families and Churches to instruct their own, this duty does not extend to State-controlled (this includes funding, even funding such as school vouchers) educational programs.