Can Science Disprove God?
Can anything ever prove something's non-existence?
In one of his essays, French philosopher Jean-Paul Sartre mentions a French Marxist writer who describes atheism as a "scientific" position. Sartre comments on this description as follows: "I recognize that in denying the existence of God, I am no less a metaphysician than was (German mathematician) Gottfried Leibniz in affirming it."
This seems to me to be one of the few things Sartre has said that is indisputably correct. Atheism is and must be a metaphysical or, at any rate, a philosophical position. And any argument for atheism will be and must be a philosophical and not a scientific argument.
A philosophical argument can, of course, have various facts established by scientific investigation among its premises. The Oxford zoologist Richard Dawkins, for example, is an indefatigable champion of atheism, and most of his arguments for atheism draw heavily on the discoveries of evolutionary biology. They are, nevertheless, philosophical arguments - as much so as Thomas Aquinas's argument for a First Mover or Descartes's argument for the immateriality of the soul. They are as much so as the arguments of those scientists of the present day who see the hand of God in the values of the parameters that occur in the laws of physics.
Now, why do I say that any argument for the non-existence of God must be a philosophical and not a scientific argument? Science has many times shown that various things that people had believed in did not exist: the spontaneous generation of life, the rotating crystalline spheres in which the planets were supposedly embedded, the canals of Mars, the influence of the positions of the stars at the moment of one's birth on the course of one's life. If science was able to show that the crystalline spheres in which the planets were supposedly embedded did not exist, why should science be unable to show that God does not exist?
Let us look at the case of the crystalline spheres. How did science show that they did not exist? The answer is simple: when the orbits of certain comets were first accurately described, it was seen that these comets passed through the crystalline spheres - or rather through the space these spheres would have occupied if they had existed. So everyone immediately concluded that the celestial spheres did not exist - although, for two thousand years, belief in the crystalline spheres was widespread.
So: scientists made certain observations; these established the orbits of certain comets and the fact that these orbits passed through the space supposedly occupied by the celestial spheres.
From the austere point of view of pure logic, observations can never establish that something does not exist.
Of course, it doesn't logically follow from this fact that the spheres don't exist. Logic, blind as justice, demands another premise: that comets can't pass through crystalline spheres (spheres strong enough to bear the weight of the planets embedded in them). But this premise is pretty obvious, and no one seriously thought of doubting it; as far as I know, no one bothered to state it explicitly. From the austere point of view of pure logic, observations can never establish that something does not exist.
Before she authorizes you to conclude that something-or-other does not exist, logic will demand more than a premise about how things look; she will require a premise of the following form: if that "something-or-other" did exist, things wouldn't look the way they do. Scientific observation is a refined way of finding out how things look; scientific observations can establish that something does not exist only when they are conjoined with a premise to the effect that if that thing existed, things would not look the way science says they look.
There would seem, therefore, to be only two cases in which science, science alone, can prove that X does not exist: when the 'if things look such-and-such a way, then X does not exist' statement that is conjoined with the observations of scientists is itself a statement that can be established by science, or when it is so obvious that it needs no support.
Scientific observation is a refined way of finding out how things look.
Science, therefore, can establish that God does not exist only if there is some scientific observation - or scientifically established fact or experimental result - such that we can look at it and say with confidence, That's not how things would be if there were a God. And this 'if' statement must either itself be scientifically established or so obvious that it doesn't need to be "established."
But all this is rather abstract. Let's look at a possible example. I have heard some people argue as follows. "There are major design deficiencies in the human eye and knee. If God existed and were even a moderately good engineer, these design deficiencies wouldn't exist. But, of course, if God existed, he'd be a rather better than moderately good engineer. So God doesn't exist." For the sake of argument, let's suppose that the design of the human eye and knee could be improved. This is not the only premise of the argument. There is another premise, an 'if' statement. Something like this: If there were a God, human beings would exhibit optimal biological design.
What sort of statement is this? Is it a scientific statement? If it is, what science does it belong to? Theobiology? I think it should be evident that this is not a statement that has been established by any of the sciences.
Suppose the argument we are examining is to constitute a scientific disproof of the existence of God. In that case, therefore, this statement must be so obvious that everyone should just accept it - accept it without argument. Is this statement that obvious? It certainly doesn't seem so to me. I can see myself believing this statement on the basis of some argument, but it doesn't seem to me the sort of thing one could believe unless someone were aware of some consideration that could be adduced in its favor.
The statement 'If there were a God, human beings would exhibit optimal biological design,' therefore, should not be accepted in the absence of any argument. Or, if that's too strong a statement, at least this much is true: no one has to accept this statement in the absence of any argument for it. No one has the right to expect that of anyone. And this isn't true of all statements. There are plenty of statements that I have the right to expect anyone to believe.
Suppose I am trying to convince you that Alice wasn't in Los Angeles at the time the crime was committed, and my argument has the (probably unspoken) premise that no one can travel from Jerusalem to Los Angeles in ten minutes. In that case, I have the right to expect you to accept that premise without argument. If you challenged me on that point, you would simply be wasting your time and mine. But if someone asserted the thesis, 'If there were a God, human beings would exhibit optimal biological design,' and if you challenged him on that point, you would not be wasting his time and yours. He might have an excellent answer to your challenge, but it would be perfectly legitimate to ask to hear what this good answer was.
Now, if someone did offer an argument for the truth of 'If there were a God, human beings would exhibit optimal biological design,' what sort of argument would it be? Well, it would be a philosophical argument. What else could it be? And here is a reasonable principle: if some premise of an argument itself requires an argument, and if any argument for that premise would have to be a philosophical argument, then the larger argument is a philosophical argument. And if this reasonable principle is, in fact, true, the argument Human beings exhibit less than optimal biological design, and If there were a God, human beings would exhibit optimal biological design; hence, there is no God is a philosophical argument, not a scientific argument, despite the fact that its first premise (we have granted this) has been established by science.
There is no God is a philosophical argument, not a scientific argument, despite the fact that its first premise (we have granted this) has been established by science.
When it comes to classifying arguments, philosophy trumps science: if an argument has a single "philosophical" premise (a single premise that requires a philosophical defense), it is a philosophical argument. But an argument is a scientific argument only if all its premises are propositions that have been established by science or propositions so trivial that they require no defense.
I make bold to say: all arguments for the non-existence of God must be philosophical arguments. So far as I can see, any argument for the non-existence of God must be of one of two types. First, it may be an impossibility argument. An impossibility argument for the non-existence of a thing is an attempt to show that the concept of that thing is internally self-contradictory or conceptually impossible - as impossible as a round square, although the impossibility may be harder to see (which is why an argument is needed to show that the impossibility exists). I shall not discuss impossibility arguments; none of them has (in my view) any merit whatever, and discussions of them tend to be rather technical - that is to say, extremely yawn-inducing in people who are not professional philosophers. I note that it is obvious that any impossibility argument would be a philosophical one.
The second sort of argument is an argument that is based on some observed fact (or facts). We have already looked at an argument of this type - the "optimal design" argument. The argument begins by stating the observed fact; it goes on to contend that this fact would not be a fact if there were a God and concludes that there is no God. My thesis is that the second premise of any such argument, the if-then premise, will never be so evident as to require no argument and that any argument for it will have to be a philosophical argument.
But why must this be? As we have seen, there are plenty of arguments for the non-existence of things that are based on observation and in which the second premise - the if-then premise - is sufficiently evident that it requires no defense. How can we be sure a priori that the case of God is different? Suppose we can prove that the celestial spheres, astrological influences, or spontaneously generated life do not exist without recourse to philosophy. How can we be confident that the non-existence of God cannot be proved without recourse to philosophy?
The answer is that there is a vast difference between God and any object or kind of thing that science has proved does not exist. Take the crystalline celestial spheres. These are really very much like the objects that we see and touch every day—it's just that, if they existed, they'd be vastly larger than the objects that we see and touch every day. But God is not like that. The idea of God is not the idea of a being that is like that. I once saw a cartoon in which a fundamentalist preacher informs his flock from the pulpit that God's socks are as big as New Jersey and his tee-shirts are the size of Texas. That preacher had the wrong idea. If he had the right idea, it would certainly be possible to prove scientifically that there was no God. If there were such a being (at least if he were anywhere around here), we'd see him, and we could measure his gravitational influence on, say, the orbits of satellites. And, anyway, there couldn't be a solid, living man-shaped being of that size. Not only would there be no possible energy source for it, but the laws of physics simply wouldn't permit it to live or maintain its structural integrity.
If God isn't like that, what is God like? Or, for those who don't believe in God, what is God supposed to be like? Well, to begin with, God is or is supposed to be omnipresent. As you might guess, this word means present everywhere. But this definition is ambiguous. Consider the luminiferous ether, that all-pervasive, perfectly elastic subtle stuff that, according to nineteenth-century physics, stood to light as air stands to sound. According to the nineteenth-century theory of light, the luminiferous ether was everywhere - in a laboratory vacuum flask, inside the earth, at the center of every star - and it was, therefore, in the most literal sense of the word omnipresent. It was present everywhere because every region of space was filled with a part of it: one part of it was conterminous with the Mississippi River, another (a large ball-shaped part) occupied the same region of space as the star Arcturus, and so on.
But God has no parts. The first of the Anglican Articles of Religion begins, "There is but one living and true God, . . ., without body [or] parts. . . ." So God can't be omnipresent in the sense that one part of him is in one place, another part in another, and some part in every place. In what sense, then, is God omnipresent? This question is best answered by means of an analogy. Consider a painting - say Rembrandt's The Night Watch. There is, surely, a very good sense (even if it is not the most literal sense) in which Rembrandt is present everywhere in that rather sizable painting. How does Rembrandt manage that? Obviously not by having one of his parts in one section of the painting, another of his parts in another, and at least one of his parts in every section. Rembrandt, unlike God, did have parts, but he didn't manage to be present everywhere in The Night Watch by distributing them across the canvas. Rather, he managed it in this wise: his creative activity is present everywhere in the painting; everything, at every point in the painting, is the way it is because it was Rembrandt's will that it should be that way; he made it that way. This bit of black here, this bit of gold there. . .they're all the way they are because those are the colors and shapes that Rembrandt's will decreed for that spot.
Similarly, God is present everywhere in the physical universe not because he is a space-occupying being who happens to be big enough to occupy all space (like the ether) but rather because every space-occupying being is a product of his creative power. This rock here, that elephant there, that neutron star over yonder, all exist and have the properties they do because it is God's will that they should. Each exists from moment to moment and continues to be the kind of thing it is only because it is God's will that it should continue to exist and be that way, and if God were to stop willing that, say, the neutron star, should continue to exist, it would vanish, all in an instant. And it is not only individual-created objects that have this feature, this continuous moment-to-moment dependency on the will of God; the laws of physics, the basic rules by which the physical universe works, stay the same from moment to moment only because that is what God wills.
Perhaps I should remind you that I am not making any existential, ontological, or factual claim when I say this. I am telling you not how things are but rather what concept the concept of God is. I am telling you what features a being would have to have to count as God. No being who is present in the physical universe otherwise than by the continuous exercise of its creative power would be God. If it should turn out that some immensely powerful and wise and ancient being made us, and if this being has a size and occupies space and has physical properties, and if there is no greater being than this, then the atheists are right: there is no God. If the immensely powerful, wise, and ancient being who made us claimed to be God, it would be either an impostor or confused. An impostor if it claimed to be omnipresent, and confused if it admitted to being a physical thing that occupied space and still claimed to be God.
In the special sense I have been laying out, Omnipresence is, therefore, an essential part of the idea of God. And this implies that God can be connected with our observations of the physical world in only the most indirect and subtle of ways. Certain medieval philosophers said that a thing that was present in a region of space by literally occupying that region, by filling it up, was "locally present" in that region. They would have summed up what I have been telling you in these words: God is locally present nowhere and totally present everywhere. (He is totally present everywhere in that the totality of his being is reflected in the sustaining power that keeps every spatial thing everywhere in the physical universe in existence from moment to moment.)
But consider. Only a locally present being can reflect light, and thus only a locally present being can be visible. Only a locally present being can exclude other beings from the space it occupies, and thus only a locally present being can be tangible. Therefore, none of our sense-organs or instruments can possibly detect God, for they can detect only locally present things. Unbelievers sometimes challenge God to come out of hiding—they refer to him as "the hidden God." But there is nothing God can do to come out of hiding, for he isn't hidden. He isn't the sort of being who could be either hidden or on display.