Craig's presentation and defense of the kalam cosmological argument is characterized with the same analytical rigour that has embodied his other works. Craig summarizes the kalam cosmological argument thusly: whatever begins to exist has a cause to account for its existence; and the since the universe began to exist, it too was initiated by an independent cause. Atheists, such as the late J.L. Mackie, deny the universe had any origion at all, and postulate a beginningless series of events spanning infinitely backwards in time. Craig counters this objection with two philosophical arguments, one courtesy of German mathematician David Hilbert.
Hilbert rejected the idea that an actual infinite amount of things can exist in reality on the basis of the absurd consequences that inevitably ensue if one accepts such a concept. To better illustrate his point, Hilbert devised an argument he called "Hilbert's Hotel," a hypothetical hotel containing an infinite number of guests. If the hotel contained a finite amount of guests and was full, a new guest would be told upon arriving that all of the rooms were full. If, however, the hotel was full, but contained an infinite amount of guests, the hotel's proprietor could shift the guests in room 1# to room 2#, the guests in room 3# to room 4#, and so forth to make room for the new guest. Yet, the number of guests would now be no greater than before the guest checked in. An even odder instance would involve an amount of guests numbering infinity attempting to squeeze into the already full hotel. In this case, the hotel's proprietor could simply create a vacancy in the odd numbered rooms by shifting guests in rooms twice their own, since they would always equal even numbers. But again, the formerly booked hotel would contain no more guests than it did before. Thus, Craig concludes from this argument that a beginningless series of events in time is impossible, since a beginningless series of events in time necessarily entails an actually infinite number of things.
Moving on to scientific evidence that confirms that the universe had a beginning, Craig makes no bones about his preference for the Big Bang model, since it lends credence to that very conviction. Craig shoots down alternative cosmological models with relative ease, starting with the Steady State Theory. The Steady State Theory posits a beginningless universe, perpetually sustained by matter left in voids created by receding galaxies. This theory lost what little credibility it had in 1965, when Arno Penzias and Robert Wilson, two scientists working at Bell Laboratories, discovered that the background of the whole universe is saturated with microwave radiation. This discovery suggests that the universe was once extremely hot and dense -- i.e., not in the everlastingly "steady" state the Steady State model holds.
Another model Craig dismantles is the ocillating model, once popularized by the late Carl Sagan. The ocillating model holds that the universe expands, then collapses back to the initial singularity, repeating this process ad infinitum. The main problem with this particular cosmological model is the complete absence of observational evidence to support it. For one thing, the ocillating model cannot explain the even distribution of matter throughout the universe. As the universe contracts, matter becomes unevenly distributed as a result of black holes which begin sucking everything up. Unexplained is how matter somehow becomes evenly distributed after the universe rebounds from its contraction phase. This is one of the many difficulties with the ocillating model, which, as far as modern physics can tell, is only a theoretical possibility, not an actual possibility.
In addition to cosmology, there are chapters on the absurdity of life without God, the historicity of the Bible, and a rational basis for affirming one's faith. This book receives my strongest recommendation.
Craig discusses many topics of importance- The Existence of God, The Meaning of Life, The Resurrection of Jesus, and more. Every topic is covered in sufficient detail, with Craig's excellent writing style and clarity apparent on every page. Craig is at his best when discussing the Cosmological Argument for God's existence. However, this is by no means the extent of his capability. He is an able defender of all the topics he covers.
One of the best features of "Reasonable Faith" is the "Practical Application" section featured at the end of each chapter. Here, Craig discusses ways in which the material provided can be of use when witnessing to others. As a consequence, Craig's book is very relevant and useful for any Christian living in today's intellectual society.
Unfortunately, Craig does not provide an organized list of "recommended further reads". Also, many of the chapters (in my opinion) focused too heavily on the historical aspects rather than the current arguments. Despite these flaws, however, "Reasonable Faith" is a valuable contribution to the Christian library from an excellent Christian scholar.
