Twenty Arguments For The Existence Of God
by Peter Kreeft & Ronald K. Tacelli
In this section you will find arguments of many different kinds for the existence of God. And we make to you, the reader, an initial appeal. We realize that many people, both believers and nonbelievers, doubt that God’s existence can be demonstrated or even argued about. You may be one of them. You may in fact have a fairly settled view that it cannot be argued about. But no one can reasonably doubt that attention to these arguments has its place in any book on apologetics. For very many have believed that such arguments are possible, and that some of them actually work.
They have also believed that an effective rational argument for God’s existence is an important first step in opening the mind to the possibility of faith—in clearing some of the roadblocks and rubble that prevent people from taking the idea of divine revelation seriously. And in this they have a real point. Suppose our best and most honest reflection on the nature of things led us to see the material universe as self-sufficient and uncaused; to see its form as the result of random motions, devoid of any plan or purpose. Would you then be impressed by reading in an ancient book that there exists a God of love, or that the heavens proclaim his glory? Would you be disposed to take that message seriously? More likely you would excuse yourself from taking seriously anything claimed as a communication from the Creator. As one person put it: I cannot believe that we are children of God, because I cannot believe there is anyone to do the adopting.
It is this sort of cramped and constricted horizon that the proofs presented in this chapter are trying to expand. They are attempts to confront us with the radical insufficiency of what is finite and limited, and to open minds to a level of being beyond it. If they succeed in this—and we can say from experience that some of the proofs do succeed with many people—they can be of very great value indeed.
You may not feel that they are particularly valuable to you. You may be blessed with a vivid sense of God’s presence; and that is something for which to be profoundly grateful. But that does not mean you have no obligation to ponder these arguments. For many have not been blessed in that way. And the proofs are designed for them—or some of them at least—to give a kind of help they really need. You may even be asked to provide help.
Besides, are any of us really in so little need of such help as we may claim? Surely in most of us there is something of the skeptic. There is a part of us tempted to believe that nothing is ultimately real beyond what we can see and touch; a part looking for some reason, beyond the assurances of Scripture, to believe that there is more. We have no desire to make exaggerated claims for these demonstrations, or to confuse “good reason” “with scientific proof.” But we believe that there are many who want and need the kind of help these proofs offer more than they might at first be willing to admit.
A word about the organization of the arguments. We have organized them into two basic groups: those which take their data from without—cosmological arguments—and those that take it from within—psychological arguments. The group of cosmological arguments begins with our versions of Aquinas’s famous “five ways.” These are not the simplest of the arguments, and therefore are not the most convincing to many people. Our order is not from the most to the least effective. The first argument, in particular, is quite abstract and difficult.
Not all the arguments are equally demonstrative. One (Pascal’s Wager) is not an argument for God at all, but an argument for faith in God as a “wager.” Another (the ontological argument) we regard as fundamentally flawed; yet we include it because it is very famous and influential, and may yet be saved by new formulations of it. Others (the argument from miracles, the argument from religious experience and the common consent argument) claim only strong probability, not demonstrative certainty. We have included them because they form a strong part of a cumulative case. We believe that only some of these arguments, taken individually and separately, demonstrate the existence of a being that has some of the properties only God can have (no argument proves all the divine attributes); but all twenty taken together, like twined rope, make a very strong case…