Absence of Evidence and Evidence of Absence: The Atheist’s Teapot Argument
Many atheists assert that they are justified in believing that God does not exist because there is no positive evidence that he does exist. They often point out in support that this is a fundamental way that we reason about things. So suppose, for example, that someone claimed that there is a teapot orbiting the Sun somewhere between Earth and Mars. As the illustration goes, we have no evidence that there exists such a thing, and so we conclude that the thing does not exist. Thus, the absence of evidence for something’s existence is itself positive evidence that the thing does not exist.
The atheist here is equating the absence of evidence and evidence of absence, and supports this equation with what we may call the “teapot argument” above. She would then argue that the case of the existence of God is analogous to the case of a teapot between Earth and Mars. In both cases we have no evidence that the thing in questions exist, and so in both cases we can conclude that it does not exist.
I argue below, however, that it is not necessarily true that the absence of evidence is evidence of absence, and that the teapot argument fails.
Answering the Atheist’s Teapot Argument
Different variations of this teapot argument have been given in different contexts. Some variations reference an invisible teapot, whereas others merely reference an ordinary, physical teapot. I submit that on neither case do we justifiably believe that there is no teapot simply because we don’t have evidence for its existence.
Consider first the claim that there is an invisible teapot orbiting the Sun between Earth and Mars. Is it necessarily true that we believe that there is no such thing simply because we do not have positive evidence of its existence? No, for there is a better reason to believe that there is no invisible teapot: an invisible teapot is incoherent and thus cannot possibly exist. Teapots are by definition physical and composed of visible matter, and thereby cannot strictly speaking be invisible. This is positive evidence for the fact that there is no such teapot.
When it comes to a physical teapot, however, such an item is coherent. If we have no evidence that such a physical teapot between Earth and Mars exists, then should we conclude that it does not exist? No, for it seems more plausible to hold simply that it may or may not exist, for all we know. We are simply left in ignorance or agnosticism with regard to the teapot. The only justification we could have for knowing that there is no teapot is if we knew that no teapot has left the Earth such that it may enter orbit around the Sun. But if we knew that, we would have positive evidence that there is no teapot.
So however we understand the teapot, the absence of evidence for such a teapot is not enough to constitute evidence for its absence.
Absence of Evidence Is Not Evidence of Absence
We may give further counterexamples to the atheist’s original claim that absence of evidence is evidence of absence. For example, we have no evidence that there is gold on Pluto, but this does not necessarily imply that there is no gold on Pluto. For all we know it’s there, but we simply haven’t found it yet. Or again, we have no positive evidence so far that there is intelligent life outside our solar system, but that does not count as evidence that there is none. We clearly are just not yet in a position to be able to determine through contemporary science whether there is life outside our solar system, and our absence of evidence is a consequence of that.
All that to say, there are cases where there is some relation between absence of evidence and evidence of absence. If we have no evidence for something when we would expect to find evidence if it were there, then that would give us some grounds for supposing that it isn’t there. For instance, if there was a horse in the room, we would expect to see it, smell it, hear it, and so forth. Given that we have no such experiences of a horse, we reasonably conclude that there is no horse in the room.
The Existence of God
The atheist may claim here that the case concerning the existence of God is like this. If God existed, we would expect to find evidence of his existence, but in fact we do not. This claim is problematic in two ways.
First, we must clarify in what way we should expect to find evidence for the existence of God. Perhaps the evidence for God is such that it is visible to all, but the only people who are able to see it are the ones who are looking for it. Or perhaps God only wants to make the evidence for his existence visible to those who are seeking him. Finally, it could simply be that we are not yet in a good position to find certain evidence concerning God given the profound nature of the subject, in which case the evidence could be there but beyond our present grasp.
The general point here is that there are different ways of understanding this expectation of evidence for the existence of God. We may not be in a position to expect a certain kind of evidence for God’s existence in the same way that we would be in a position to expect sensory evidence for the existence of a horse in the room. Hence, it could very well be that the atheist expects a certain kind of evidence for God (such as a neon sign in the sky reading “God exists”), of which there is none, but that there are still other kinds of positive evidence available.
This leads to my second point, which is that it is false that there is an absence of evidence for God’s existence. Prominent arguments for the existence of God are based on the discovery of the beginning of the universe, the exquisite fine-tuning of the universe to permit intelligent life, the experience of objective moral values and obligations, personal experience of God himself, and so forth. Hence, if the teapot argument for atheism is to go through, it must do so only after it is shown that the above evidence is not really evidence after all, and that is no easy task.
The absence of evidence by itself is not necessarily evidence of absence. Thus, it is not enough to justify atheism to say that there is no evidence for God. The existence of God may well be compatible with the absence of the kind of evidence that the atheist expects, as well as the absence of any kind of evidence in our possession. The claim that there is no evidence for God is also highly questionable.
In short, in denying the existence of God the atheist is making a substantial knowledge claim, and she will need to provide some sort of positive argument or evidence in support of that claim if she wants us to rationally accept it.
What do you think about the relationship between the absence of evidence and the evidence of absence? Let me know any of your thoughts or questions in the comments section below!