Graeme Goldsworthy in his book Gospel and Wisdom (part of the Goldsworthy Trilogy, Paternoster, 2000), which i’m reading for a course in Old Testament Poetry and Wisdom Literature, presents the following brief and helpful discussion of the relationship between true and exhaustive knowledge, and how this applies to the Christian and non-Christian.
[T]he empiricist or humanist will claim to know things truly while not knowing exhaustively. In this he is inconsistent. No humanist would say that things exist in total isolation from each other. For a start he couldn’t investigate them if they did, for they would also be isolated from him. And there could be no such things as natural laws, or complexities of matter, for there would be only random particles. There would be no organisms, no people to become humanists! Once we recognize this, we will see that what things really are includes their relationship to everything else. When the humanist claims to know something truly, he is saying that he knows how it relates to everything else in existence. In other words, to know even one thing truly he must know all things exhaustively.
We can summarize this discussion by a contrast of three positions. First, the atheistic humanist claims to know enough to say that God does not exist. This is a claim to know everything, for if he admits that he does not know everything, how does he know that God is not included in what he does not know? Secondly, the agnostic humanist things to avoid the problem of the atheist by saying that we cannot know if God exists or not; he may or he may not. But this is also to claim exhaustive knowledge, for how can he know that God’s existence cannot be known other than by knowing everything there is to be known? The last thing left for him to discover may be the evidence that God either exists or does not exist. Finally, the Christian knows that he does not have exhaustive knowledge. But he knows also through revelation that God does have exhaustive knowledge and can therefore define for us what reality is. By the same revelation this God has told us all that we need to know in order to know truly. The Christian can know God truly. He can know man truly, and the created order truly. He knows none of them exhaustively, but he does know them truly.