Why Evolution Works (and Creationism Fails)

Foreword

xiii Foreword Some time ago after a public lecture I gave, I had the pleasure of a long and fascinating conversation with several young men who were obviously very intelligent, educated, conservative Christians. They had good questions and they listened to what responses I could offer them, and in return, they were able to ponder some of my own questions for them and provide good answers. They asked me why, if evolution was governed by random processes, it was not completely incompatible with the idea that there was a purpose and meaning to life, one that could be directed by a divine Creator.This is a good question , but it also begs the question that evolution is in fact governed by random processes. It isn’t. Natural selection, the great insight of Darwin and Wallace, is anything but random,which is also true of sexual selection,Darwin’s other great evolutionary process. In fact, I don’t know of any really important processes in evolution that are random (random drift is one,but we don’t know how important it is;neutral evolution isn’t important to evolution until something happens to it, which is usually selective).When we talk about “random mutations,” we’re not talking about causes or effects of mutations (anything can’t happen), but about the distribution of predictable effects of mutations in populations (we can know risk factors, causes, and statistical incidences, but we can’t predict in advance which individuals will be affected). For scientists, “random” is just a term that describes the statistical distribution of some known effect in a sample. So, if evolution is not random, does it still deny a purpose or meaning to life? These really aren’t questions for science, at least in the sense of ethics, aesthetics, or morals.The purpose of life is to make more life: to survive and reproduce.This is not a conscious purpose of any organisms except humans, as far as we know, but without surviving and reproducing, a species becomes extinct.Then, does life have a direction?The only direction in science is time, and we know from our studies of the evolution of life that species have evolved through time by changing and adapting to whatever the physical environment and other organisms throw at them. This history—or macrohistory , if you will—is certainly a direction, a chronicle of events and changes through time from which we derive ideas about patterns and processes. And beyond this, science does not go. Prelims.qxd 3/26/09 5:36 AM Page xiii But, one of my companions asked, if you don’t have the fear of losing salvation to provide the basis for your morality, what’s to stop you from killing this guy next to you and taking his stuff? I really didn’t know, but I replied by asking him why he would want to do that. Wouldn’t he regret it? Wouldn’t there be reprisals, pursuit, conviction in a court of law? Wouldn’t he feel terrible for the victim’s friends and family? My companions replied that they could not understand how a system of morality could be built without being based on the fear of divine retribution. So, apparently, for them the problem of good and evil is purely theological, not rational. Upon further questioning it turned out that my companions had not read Plato, and so could not conceive of the idea of the Good in a purely philosophical sense that could be put into social practice.There is also a long tradition of deriving morality from biological principles, and these are discussed in this book. In America today, and in some other parts of the world, we face a dichotomy of approaches to the world. One is authoritarian, based on the primacy of revealed knowledge that is subject to discussion and examination (and sometimes to revision, though this is not always admitted), but not to test and refutation.This approach is religious, and is based on sacred texts whose wisdom is not questioned; if secular experience is contrary to sacred revelation, the former must be wrong, not the latter.The second approach to the world comes from the Enlightenment, and regards reason, rationality, and empirical experience as the best guides to navigating the real world—by which is meant the understanding of the natural world as well as the development of moral, social, and political precepts. It admits useful ideas from theology and religion, but...