The non-Christian scientist must be told that he is dealing with facts that belong to God. He must be told this, not merely in the interest of religion in the narrower sense of the term. He must be told this in the interest of science too, and of culture in general. He must be told that there would be no facts distinguishable from one another unless God had made them and made them thus. He must be told that no hypothesis would have any relevance or bearing on these same facts, except for the providence of God. He must be told that his own mind, with its principles of order, depends upon his being made in the image of God. And then he must be told that if it were not for God’s common grace he would go the full length of the principle of evil within him. He would finish iniquity and produce only war. His very acts of courtesy and kindness, his deeds of generosity, all his moral good is not to be explained, therefore, in terms of himself and the goodness of his nature but from God’s enabling him to do these things in spite of his sinful nature. “Will you not then repent in order to serve and worship the Creator more than the creature?”
– Cornelius Van Til, Common Grace and the Gospel p.165-166
Augustine of course stood squarely for the Pauline principle, having told us that the whole of history consisted of one deadly, no-give, no-take combat between two “cities,” that of God and that of man, the “citizens” of the former kingdom being in basic disagreement with those of the latter on the respective questions of the beginning, the middle, and the end of history. To be sure, citizens of the kingdom of God must not press upon those of the kingdom of man what Jesus said to the Pharisees, namely, that they be of their father, the devil, since only Jesus knew the heart of man. Thus, His followers may speak only of the two opposing principles activating men. Similarly, it is not possible for them to predict in each instance whether a certain individual belongs to one kingdom or the other, as history is never and nowhere a finished product. Nonetheless, there are two main and exclusive tendencies in it: men are in their hearts either for or against the Christ whom Paul preached, and what is in their hearts will usually find expression in the sympathies manifested by their actions.
– Cornelius Van Til, Who Do You Say That I Am p.33-34
The non-regenerate man seeks by all means to “keep under” this remnant of a true theistic interpretation that lingers in his mind. His real interpretative principle, now that he is a covenant-breaker, is that of himself as ultimate and of impersonal laws as ultimate. It is he himself as ultimate, by means of laws of logic that operate independently of God, who determines what is possible and probable. To the extent, then, that he proceeds self-consciously from his own principle of interpretation, he holds the very existence of God, and of the creation of the universe, to be not merely improbable, but impossible. In doing so he sins, to be sure, against his better knowledge. He sins against that which is hidden deep down in his own consciousness. And it is well that we should appeal to this fact. But in order to appeal to this fact we must use all caution not to obscure this fact. And obscure it we do if we speak of the “common consciousness” of man without distinguishing clearly between what is hidden deep down in the mind of natural man as the revelation and knowledge of God within him and what, in rejecting God, he has virtually adopted as being his final interpretative principle.
– Cornelius Van Til, An Introduction to Systematic Theology p.82-83
Thus we have the “relative good” in the “absolutely evil” and the “relatively evil” in the “absolutely good.” Neither the “absolutely evil” nor the “absolutely good” are epistemologically as self-conscious as they will be in the future. God’s favor rests upon the reprobate and God’s disfavor rests upon the elect to the extent that each lacks epistemological self-consciousness. In neither case is it God’s ultimate or final attitude, but in both cases it is a real attitude. As there is an “old man” in the believer, so there is an “old man” in the unbeliever. As there are the remnants of sin in the believer, so there are the remnants of the image of God in the unbeliever. And as the “old man” in the believer does not, in the least, detract from his status as believer, so the “old man” in the unbeliever does not, in the least, detract from his status as unbeliever. Each man is on the move.
– Cornelius Van Til, Common Grace and the Gospel p.109
In Calvinism more than in any other form of Protestantism the message of Christianity is clearly presented as a challenge to the wisdom of the world. The natural man must not be encouraged to think that he can, in terms of his own adopted principles, find truth in any field. He must rather be told that, when he finds truth, even in the realm of the “phenomenal,” he finds it in terms of principles that he has “borrowed,” wittingly or unwittingly, from Christianity. The fact of science and its progress is inexplicable except upon the presupposition that the world is made and controlled by God through Christ and that man is made and renewed in the image of God through Christ.
– Cornelius Van Til, The Case for Calvinism p.106-107
In view of the facts mentioned above we shall have to concern ourselves first and primarily with the two opposing principles of interpretation. The Christian principle of interpretation is based upon the assumption of God as the final and self-contained reference point. The non-Christian principle of interpretation is that man as self-contained is the final reference point. It is this basic difference that has to be kept in mind all the time. It will be difficult at times to see that such is actually the case. The very fact that by God’s common grace fallen man is ‘not as bad as he could be’ and is able to do that which is ‘morally good’ will make the distinction between two mutually exclusive principles seem an extreme oversimplification to many.
In fact, it is in spite of appearances that the distinction between the two principles must be maintained. The point is that the ‘facts of experience’ must actually be interpreted in terms of Scripture if they are to be intelligible at all. In the last analysis the ‘facts of experience’ must be interpreted either in terms of man taken as autonomous, or they must be interpreted in terms of God. There is no third ‘possibility.’ The interpretation which takes the autonomous man as self-interpretive is an ‘impossible possibility.’
– Cornelius Van Til, A Christian Theory of Knowledge p.44-45