Schaeffer's influence on evangelicalism in the 20th century is incalculable and overwhelmingly positive. In this book Schaeffer challenges Christians to engage with modern culture where it is at, particularly by discovering modern man's presuppositions and forcing him to recognize the final end of those presuppositions. He suggests that in the end, every worldview except the Christian worldview will prove to be inconsistent. Schaefer's main paradigm in the book involves the "line of despair," below which a man has fallen when he refuses to recognize the reality of thesis and antithesis. According to Schaefer, modernity has fallen below this line, and as Christians we must address this problem before we address the problem of man's guilt before God.

For all of its strengths, this book is thin in places. Schaefer doesn't spend as much time as I wish he would explaining himself. I also wish he would have spent more time in his section on critiquing art. Even though I often found myself wanting him to elaborate, Schaeffer does make me want to strive to engage culture more and to do so in an apologetically Christian way.