Reason must know its limits in order to be truly reasonable.
Rancho Sante Fe, Calif.
Religion has faced formidable foes in its history. But atheism hasn't generally been one of them – until today. A recent string of bestselling books has put believers of all stripes on the defensive. Religion, say authors such as Richard Dawkins, Daniel Dennett, and Christopher Hitchens, is an unreasonable form of blind faith, often leading to fanaticism and violence. Reason and science, they contend, are the only proper foundations for forming opinions and understanding the universe. Those who believe in God, they insist, are falling for silly superstitions.
This atheist attack is based on a fallacy – the Fallacy of the Enlightenment. It was pointed out by the great Enlightenment philosopher Immanuel Kant. Kant erected a sturdy intellectual bulwark against atheism that hasn't been breached since. His defense doesn't draw on sacred texts or any other sources of authority to which people of faith might naturally and rightfully turn when confronted with atheist arguments. Instead, it relies on the only framework that today's atheist proselytizers say is valid: reason. The Fallacy of the Enlightenment is the glib assumption that there is only one limit to what human beings can know – reality itself. This view says we can find out more and more until eventually there is nothing more to discover. It holds that human reason and science can, in principle, unmask the whole of reality.
In his 1781 "Critique of Pure Reason," Kant showed that this premise is false. In fact, he argued, there is a much greater limit to what human beings can know. Kant showed that human knowledge is constrained not merely by the unlimited magnitude of reality but also by a limited sensory apparatus of perception.
Consider a tape recorder. It captures only one mode of reality, namely sound. Thus all aspects of reality that cannot be captured in sound are beyond its reach. The same, Kant would argue, is true of human beings. The only way we apprehend empirical reality is through our five senses. But why should we believe, Kant asked, that this five-mode instrument is sufficient? What makes us think that there is no reality that lies beyond sensory perception?