"This book is about the war between God and fallen man."
If you were to put "The Divine Challenge" in a particular genre, it would probably be classed as apologetics. The author (a professor of mathematics who earned his Ph.D. in astronomy, which makes his book doubly interesting) presents himself with, pun intended, a challenging task: to show the basic presuppositions of the major worldviews of the day, especially naturalism, and how they fail to answer many of the basic questions of life. Chapter by chapter he deals with the fundamental, undeniable pillars of our world - matter, mind, and mathematics - and ties them off with the universal quest for meaning. Is there any meaning in the world? Does "blind chance" exist? Does belief in miracles undermine the practice of science? Can nonphysical mind arise from matter? These are a handful of the extremely important questions he addresses.
Many of the points he raises are fairly obvious if you stop and think things through, but he lays them out in a neat, logical format. I confess I struggled at times to understand some of his chapters, especially those on mathematics and the Christian view of mathematics; but nevertheless, I wouldn't call this a difficult book. It is very accessible, even for those who haven't studied philosophy or logic. And, what is more important, The Divine Challenge is a timely and appropriate book. Published a decade ago, its observations and criticisms continue to hold true. Thus I highly recommend it as a start to any study on worldviews and their presuppositions - including Christianity's.