I hear a lot of atheists complaining that they shouldn’t have any burden of proof because it is impossible to prove a universal negative, i.e. – “there is no God”.
Here’s a post from William Lane Craig about it.
The first claim is, ironically, usually found on the lips of atheists, who thereby seek to excuse themselves from bearing any share of the burden of proof in the discussion. Usually, the claim is that a universal negative cannot be proved, and therefore the claim that “There is no God” is unprovable. The second claim is typically given as the reason why a universal negative cannot be proved: no matter how much knowledge you have acquired, there will always be more facts that you do not yet know, and perhaps the exception is among them. So one can never prove that there is no God. Perversely, this is somehow interpreted, not as an admission that atheism is indefensible, but as a demonstration that it is in no need of defense!
Unfortunately, the argument is misconceived on a couple of counts.
First, negative, universally quantified statements can be proved. We do this all the time. When we make statements about “all” or “none,” we are speaking about what is the case with respect to a certain domain. We are saying that all or none of the members of that domain have or has a certain property. If the domain is not too large, I can confidently make universally quantified affirmative and negative statements. For example, I am quite confident that “No U.S. Senator is a Muslim.” Or again, if I have a typical sample of the domain, I can make inductive inferences on the basis of the evidence from the sample to the whole, even if the whole domain is too large for me to canvass; for example, taking as my domain all the microbes on Earth, I can confidently assert, “No microbes have brains.”
Now someone might say that while it is admittedly true that negative, universal statements can sometimes be proven, still the point remains that in the case of God, the domain is too large and our sample too small to come to any negative conclusion. But those who propound this argument seem to think that the way one determines whether God exists is by taking a sort of universal survey to see if anything answering to the description of God exists somewhere out there. There are, however, other ways of coming to a knowledge of negative, universally quantified statements than doing an inductive survey.
For example, we can have knowledge of negative, universally quantified statements on the basis of things’ essential properties; for example, “No water molecules are composed of CO2.” (Even if something looked and behaved just like water but was made of CO2 , it still would not be water but just a look-alike substance.) Or if we could show that a notion is logically impossible, we would know that it does not exist; for example, “There are no married bachelors.” Significantly, many atheists have tried just this route to proving that God does not exist, arguing that the idea of a being which is all-powerful or all-knowing is logically incoherent.
[...]Second, the statement that “God does not exist” is not a universally quantified statement. When the theist asserts that “God exists,” the word “God” is being used as a proper name, not as a common noun. It is not a statement like “Dogs exist” but rather like “Lassie exists.” In order to prove that God does not exist, one need not prove that there are no gods whatsoever. Our interest is in one specific being, not in all the other beings which may have been imagined or worshipped throughout the world. So the claim that “God does not exist” is really a singular claim, like “Sherlock Holmes does not exist” or “Harry Potter does not exist.” No one thinks that negative, singular claims cannot be proven.
So there are two ways to disprove a universal negative. Look where you expect the thing to be evident, and show that the evidence is not there. For example, show evidence that the universe is eternal. You can’t have a Creator if you can show evidence that the universe is eternal. The second way is to show that the concept of God is logically contradictory, e.g. – that the concept of a “timeless person” is self-contradictory. Scholarly atheists try to do this, but this has not filtered down to the rank and file, which is why they still hold to these atheist slogans like “you can’t prove a universal negative”. Of course you can.
And finally, Craig concludes with some good advice:
The bottom line is that we have no choice but to go on the basis of the knowledge and evidence that we do have—just we do in all other affairs of life.
Rank and file atheists seem to be very keen on holding out for today’s scientific and historical data to be overturned by Star Trek theories of the future. But the more we study the good, scientific arguments for God’s existence, the harder it is for naturalism to account for it. I am talking about the origin of the universe, the cosmic fine-tuning, the habitability argument, the origin of life, the origin of phyla, scientific evidence for consciousness and free will (e.g. – mental effort) and so on. Not to mention other arguments like the moral argument and the minimal facts case for the resurrection of Jesus.
We have to decide on the data we have now. And the data we have now fits better with a theistic worldview than an atheistic worldview. I can imagine all kinds of data that would argue against Christian theism. Finding the bones of Jesus. The universe being eternal. Experimental evidence for the multiverse. A probable naturalistic scenario for the origin of life. Etc. Arguing against Christian theism is not hard, it just takes work. That’s why intelligent and informed atheists like Peter Millican and Austin Dacey can do it, but rank and file atheists want to talk about “I lack a belief in God” and “I can’t prove a universal negative”.
No one is asking atheists to prove anything, just as theists don’t prove anything. We are asking them to give logical arguments with premises that are supported by the evidence. And that’s what we expect theists to do, too. Once we have all the arguments and evidence on both sides, then people can decide for themselves. You don’t have to “prove” anything in a debate, you just have to state your case as persuasively as possible and the other side does the same, then people decide. Simple.
UPDATE: My favorite atheist Jeff Lowder mentioned this post from Internet Infidels which is on the same topic. His perspective is always worth reading.
UPDATE: And my friend John Fraser has some thoughts on evidence for and against God.
UPDATE: My FB friend Bruce sent me this video:
It’s William Lane Craig answering the question in a debate situation.