It is hard to imagine any institutions in human culture and existence today with deeper roots than religion and science. Religion is so basic to human history that the human species has been called homo religiosus, the religious animal. Indeed, some scholars even connect the origins of our species, Homo sapiens sapiens, to the first archeological signs of religious rituals and practices. A huge proportion of the world’s population today is identified with at least one of the major religious traditions of the world. It is equally impossible to imagine humanity without science. By 1900, about three centuries after the dawn of modern science, it was clear that this new means of studying the natural world and organizing our beliefs about it was transforming humanity more than perhaps any other development in the history of our species. By the end of World War II, when much of Europe had been reduced to rubble and Hiroshima to an atomic fall-out zone, science had changed the face of the planet for ever. Today there is virtually no aspect of human existence that does not depend in some way upon scientific results and technological inventions. From immunizations to heart surgery, from fertilizer to genetically modified crops, from our cell phones to our computers, from roads to airplanes, from the bananas on our table to our ‘cash’ in the bank, existence without science has become inconceivable. As we will see in the following pages, the impact of science is not only limited to its products. The scientific mindset has transformed humanity’s views of what knowledge is, how it is obtained,

and how knowledge claims are evaluated. Even people whose central moral and religious beliefs are not determined by science are still impacted by the growth of science, since others will judge their knowledge claims in light of their agreement with or divergence from scientific results. Science and religion: compatibility or conflict? Should we talk about ‘science and religion,’ or should it be ‘science versus religion’? By the time you finish this book, you will have a good sense of the whole range of answers that have been given to this question and the best arguments that are being made on both sides. This should give you enough information to make up your own mind and to defend your own positions in each of the major areas of the debate. Certainly the dominant message in our culture today is that science and religion stand in deep tension. Nowhere is this message clearer than in the debate between naturalism and theism. Naturalism is the view that all that exists are natural objects within the universe – the combinations of physical mass and energy that make up planets and stars, oceans and mountains, microbes and humans. In normal usage, naturalism usually implies the claim that real knowledge of these natural objects comes through, or is at least controlled by, the results of scientific inquiry. Cognate terms are materialism and physicalism. The former has traditionally meant ‘all is matter’; the latter technically means reducible to the laws, particles, and forms of energy that physicists study. Theism is the belief in the existence of God, an ultimate reality that transcends the universe as a whole. Passing over a few exceptions, Jews, Christians, Muslims, and Hindus are theists. When the term is used broadly, it includes pantheists, panentheists (‘the world is in God’), and polytheists – hence most of the native African religions and the world’s indigenous or tribal religions. Typically God is described as a personal being, often with the qualities of omniscience (all-knowing), omnipotence (all-powerful), and omnibenevolence (all-good). Based on the sacred scriptures of their particular tradition (the Bible, the Qur’an, the Upanishads), theists often ascribe other qualities to God, such as consciousness, love, justice, and righteousness. Theists usually defend specific ways of knowing, distinct from science, through which humans are able to know something of God and God’s nature. Traditionally, they have believed that God

created the world, providentially guides it, and reveals God’s self in it. This means that God does things in the world (‘divine action’), carrying out actions that are either consistent with natural law or that involve setting natural regularities aside (miracles). At first blush, theism and naturalism appear to be incompatible positions. Naturalists affirm that all that exists is the universe (or multiverse) and the objects within it, whereas theists claim that something transcends the universe. Naturalists generally use science as their primary standard for what humans know, whereas theists defend other ways of knowing as well, such as intuition or religious experience. So let us explore. Are the two positions incompatible? Or, when one probes deeper, can one detect any deeper compatibilities? The best way to find out is to arrange a debate between a knowledgeable representative from each side and then to see what emerges. As you know, good debates between naturalists and theists in real life are hard to find; they often deteriorate into name-calling and shouting matches. Fortunately, in a book it is possible to imagine a calm and civil discussion between defenders of the two positions:

Host: The definitions of your positions have already been presented. So let me ask each of you to give a basic defense of your position. Let us start with the theist. Theist: Religion is one of the oldest and most notable features of humanity. Some of the greatest wisdom and some of the most ennobling ethical ideals are contained in the world’s religious traditions. These ideals are intrinsically linked to metaphysical beliefs, beliefs about the nature of ultimate reality. In my particular case, for example, I believe that an infinite personal being exists, one who is the Creator and ultimate ground of all finite things. Naturalist: I don’t dispute the role that religions played in the childhood and youth of our species. Indeed, although much evil has been done in the name of religion, I concede that it has sometimes also brought some good. But humanity in its maturity has invented science and begun to guide its decision-making by scientific results. If religion is to play any positive role today – and at least some of my naturalist friends believe it still can – it must

function in whatever spaces are left over by the results of the various sciences. T: There is no reason to think that the advent of science spells the death of religion. I advocate a more complex worldview, in which both serve important functions. I agree that religion should not compete with science in science’s own proper domain, but many of the most important human questions lie outside the sphere of scientific competence. Host: Thanks for those opening statements. Here’s our next question. Are there areas of human experience, outside the domain of science, where religion provides knowledge? T: Science describes what is but cannot tell us how we ought to act. Hence, ethics and morality lie outside its sphere. Science can tell us about the laws of nature and can explain the motion of physical bodies in the universe, but it cannot tell us what came before the universe or why it was created. Yet for many of us the meaning of human life turns on questions like these, questions about the ultimate nature of reality. Religion provides knowledge in these spheres. N: You wrongly set limits on science, for example, by claiming that it has no moral implications. For example, there are values that arise in the process of doing science, and these provide good models for human interactions, for institutions, and for politics.1 To know what kind of animal we have evolved to be tells us something about how we should live if we are to be happy and successful. Hence science does provide some guidance for how humans ought to live. Of course, many human decisions are not dictated by physics or biology. In cases where there is great variability across cultures and moral systems, and where the beliefs in question do no damage, we can be relativists, allowing each person to choose for himself or herself. Religion falls in this category. And on the meaning question: I find meaning in the pursuit of knowledge about the world, as well as in my family, friends, and hobbies. What more meaning do I need? Host: Okay, next question. Does anything exist beyond the natural world taken as a whole? N: I think such questions are meaningless. We can observe empirical objects; we can measure them and make predictions about their causal interactions with each other. Why would we

want to make truth claims about the existence of anything else? I tend to think that all such metaphysical language is literally meaningless – sort of like the famous poem from Lewis Carroll’s Alice in Wonderland: ‘ ’Twas brillig and the slithy toves did gyre and gimble in the wabe . . .’ T: I think I can show that it’s impossible to argue against metaphysics (in this case, belief in God) without doing metaphysics, and therefore contradicting oneself. I also think that a number of positive arguments can be given for affirming the existence of God. I don’t actually share the view of a school called ‘Intelligent Design,’ which claims that these arguments are scientific arguments and can win in a head-to-head competition with contemporary scientific accounts of the world. They are to me instead philosophical arguments. But I think they are compelling nonetheless. I affirm the classical proofs for the existence of God: the ontological, cosmological, and teleological arguments. They do not force belief in the existence of God, but they at least show that it’s not unreasonable to believe in God. N: Those classic arguments are no longer persuasive in the scientific age. Some of them make assumptions about nature that we no longer hold today. For example, the teleological argument, the so-called argument from design, is no longer valid after Darwin. It argues that God exists based on the fact that animals and plants are matched to their environments; otherwise, it says, it would be impossible to explain why organisms are so perfectly suited to their surroundings. But Darwinism as a whole explains evolution and adaptation in scientific terms. T: I agree that modern biology has rendered certain forms of the argument from design unconvincing. So let me give two arguments drawn from the context of modern science, which I think are still persuasive. The first is the ‘fine-tuning’ argument. We now know that the fundamental physical variables had to fall within a very narrow range for life to be possible, and in fact they do. This suggests that we live in an ‘anthropic’ universe – a universe designed for life, or at least the only kind of universe in which life could arise. As the cosmologist Edward Harrison writes somewhere, ‘Here is the cosmological proof of the existence of God. The fine tuning of the universe provides prima facie evidence of deistic design. Take your choice: blind chance that requires multitudes of universes, or design that requires only one.’