The description of the book is a follows:
Concentrating on what he considers the two most strategic priorities of Christian apologetics -- the existence of God and the authority of the Bible -- this respected theologian surveys history's stream of thought, uncovers the common ideologies that work against faith, and affirms four principles of knowledge that are essential for all legitimate discussion. Sproul's work provides a convincing, logical defense of the faith that will prove an indispensable resource for personal, small-group, or classroom study.
There were a few points in which I did not entirely agree with the author. For example, he states on page 81, "...we can learn through science that the moon reflects light, but to our eyes it looks like a generator of light, and the Bible in fact describes it as such (Gen. 1:14-19). Is the Word of God therefore wrong? No, because its author was not intending to teach us about the moon's refecting of the sun's light but rather about how God divided the days from the nights..." On the surface, this is a true statement -- that the Word of God is not wrong simply because man does not understand it; however, there is one point to consider which the author did not bring out: that while the Bible writes from the point of view that the moon is a generator of light, it is probably because the author is writing it from the perspective of a viewer from earth; there are many instances of this in Scripture. So while I agree with the author's conclusions, I do think he should have added this last point so that any skeptic reading the book would not look at it as a contradictory statement.
However, I really enjoyed the book. Pages 111 and 120 had some great information on why spontaneous generation and chance don't work in the evolutionionary theory. Sproul also had some good points demonstrating that our faith is not a blind faith, and I loved how he applied the law of causality and the law of non-condradiction to the Scriptures to show that it is important to the Christian worldview (pg 60).
The main thesis of the books seems to be summed up by the following statement: "Virtually every attack against theism involves a rejection of one or more of the four basic necessary principles for human knowledge: 1) the law of noncontradiction, 2) the law of causality, 3) the basic reliability of sense perception, 4) the adequacy of human language to communicate. All four of these principles are assumed throughout the Bible. They are also assumed in the scientific method. They are all necessary instruments for knowledge -- indeed for all science. All denials of these basic principles are FORCED and TEMPORARY. People deny them only when they have vested interest in their denial. But these denials do not last long. They cannot last long, for these principles are necessary for surviving as living creatures." (pg 69)
In summary, I thought Sprouls book was a very straightforward attempt to demonstrate the rational basis of Christianity. At times, the wording got technical when Sproul added some background information (for example, on Kant's view); but generally speaking, everything was easy enough for any lay-person to understand and implement. This summary by Faith & Mission sums the book up perfectly:
Sproul, in his typical lucid, straightforward style, offers a much-needed reassessment of rationalbased apologetics. He answers well Scaeffer's call for a pre-evangelism that can reunite faith and reason, rational principles and spiritual truth-claims.