Perhaps I'm dense or I just haven't read the right book yet.
But I've heard frequently in the discussions of God's exitence or lack thereof the statement (and I paraphrase) "You can't prove God doesn't exist because you can't prove a negative."
And that seems to be a conversation stopper.
But I've never heard any proof for the statement that you can't prove a negative.
The claim that one cannot universally and unequivocally prove that God doesn't exist is valid, because yes, proving a negative is impossible. Bertrand Russell proposed the unfalsifiable idea of a teapot orbiting the sun somewhere between earth and Mars, and Dawkins uses this idea in his book The God Delusion. Of course neither Russell, Dawkins, nor anyone else on earth thinks that a teapot is orbiting the sun, yet none of us can unquestionably disprove it. Another somewhat humorous hypothetical worth considering is Pastafarianism, a satirical statement about God and creationism. It is a "religion" claiming that the "Flying Spaghetti Monster" created the universe. The whole system is of course absurd on purpose; its point is to show that no one, not creationists or even scientists can prove that such a being does not in fact exist and did not in fact create the universe. Similar to the idea that a teapot is orbiting the sun, no one believes this, but no one can fully disprove it either.
I have often heard this statement when theists try to point out that atheism is irrational because a universal negative cannot be proved: "Absence of evidence is not evidence of absence." That statement is true, but only tenuously so because it hinges on the use of the word "evidence." To show the validity of an atheistic position, I modify the sentence this way: "Absence of evidence is support of absence." Since there is no evidence that Apollo, Tabaldak, the Flying Spaghetti Monster, or the biblical God exists, that supports their nonexistence, though of course it does not absolutely prove it.
Hopefully that makes sense. It is true that one cannot prove a negative, but this by no means needs to be a conversation stopper. It is logical to assume that something does not exist if no support or indications of its existence can be found, but it is illogical to claim that that such a thing absolutely and without question does not and has never has existed. The former is the position of nearly all atheists; the latter is the straw man that theists knock over.
But I've never heard any proof for the statement that you can't prove a negative.
That's because it's not true, it's an oversimplification of an occasionally valid claim. There are tons of negative statements proved in mathematics, for example, there is no rational number whose square is 2 or the number pi is not rational can be proved.
The better—but still false—claim is that you can't prove negative existential claims, that is to say, a statement of the form: there are no _____. (The classical example is there are no black swans.) The reason given for this claim, which is often false for particular cases, is that to prove it, you would have to examine every swan in existence. If there are very many swans and they are spread throughout the entire universe, this is clearly an impossible task. However where the candidates to be examined are few in number and easily located this is not the case. For example, there are no works by Gassendi in our Carlsbad library is rather easily proved by checking the catalogue or the shelves. A surgeon may establish that there is no sponge left inside the patient by accounting for all those used in the operation.
There may be other reasons you cannot disprove the existence of gods or of the Christian God, but it's not because you can't prove a negative. In the case of God, I would say the principal reasons are lack of definition and postulation of unsensibility.
Can't agree with this.
The claim that one cannot universally and unequivocally prove that God doesn't exist is valid.
The sentence is grammatically correct. But that doesn't mean it has any meaning.
The reason is that the word 'God' has no definition. God is a meaningless word. So before we even get started on God, we need a definition of God and a place where God exists. If there is no definition of God or place where he exists, then what are we proving or disproving?
If we compare 'you can't prove there are no black swans' with 'you can't prove there is no God', there is a difference. We know swans exist. We know their features, the environments the live in, their genetic make up. We just need to find a black one in a place that exists. Or, in today's world of science, we could probably genetically manipulate some part of the swan genome to produce a black swan.
When somebody says 'dog' to me, I know pretty much what they mean. I don't know exactly what they mean, because of the variety of dogs that exist, but I have a good idea. And the same goes for banana and cat. BUT what about God. For me, I draw a blank in my mind when I think about God. Zero. Nothing. It doesn't exist. Probably because I have no personal definition of God.
Can it be proven there is no tea pot orbiting the Sun? Maybe. First we would need to find the size of the average tea pot. Then we could calculate the distance and speed needed for a tea pot to orbit the Sun without it falling into the Sun or drifting off into space. Additional considerations would be the orbit of Mercury and other planets. So even Bertrand Russell's tea pot may be falsifiable because tea pots exist as does the sun. I wonder if there is a Goldilocks zone in the Sun's gravitational field for Tea pots.
Skeptic had an article on just this topic.
It's a good article in general, but does not adequately explain where the notion came from—namely, from the idea that you can't prove an existential negative, which although not true in general is true in some particular cases.
I wonder if there is a Goldilocks zone in the Sun's gravitational field for Tea pots.
Perhaps teapots collect at stable Lagrangian points.
Found this to be a good explanation of them.
Some astronaut really ought to kick a teapot out into orbit sometime.
By a negative, it means the complete absence of a particular "thing" from the universe, typically "God", or the flying spaghetti monster or unicorns, ie. it's non-existence. This is only true if the "thing" has no properties which we can detect.
The negative: "There are no eggs in this egg carton", is easy to prove - just have a look. The properties of egg-ness and egg carton-ness allow us to check.
But what of "God"? What properties does "God", (if there is such a thing), have? Are these god-properties testable? If there are no testable properties of "God", then "God" actually has the same properties as a non-existent "thing". But "God" does, it is claimed in theology, have some properties which are testable, and have been tested.
For example "God" supposedly answers intercessionary prayers, ie. "he" will intercede in the lives of people, in response to prayer. Carefully conducted statistical experiments show that the outcomes for patients with life-threatening illnesses is no better, and sometimes worse, for those patients whose healing is prayed for, en mass, (ie. by whole church congregations).
We can conclude from that, that there is no evidence for a god that answers prayers under those circumstances. There is a website called 'Why Wont God Heal Amputees ?', (http://whywontgodhealamputees.com/). The idea is that sometimes people claim "God" has helped in their healing, but that is just a good imagination - they heal godlessly, but attribute their good fortune to "God". On the other hand, good fortune cannot grow back an amputated arm or leg or finger etc. This complete failure of "God" to heal amputees is strong evidence that "he" does not exist. It is the impossibility of good fortune in amputee healing, which explains "God's" failure in that arena.
"God" is also supposed to do miracles, but it has never be verified that miracles have occurred. The Roman Catholic Church say that miracles have been done through the saints, but they have a vested interest in finding truth in miracles. What evidence of miracles is ever passed on to the more sceptical scientific community for verification ? None! Furthermore, unexplained events may be explicable in the future, as our knowledge of nature increases.
Also, "God" is supposed to have made prophesies, but they have never been shown to pan out. Prophesies tend to vague, open-ended, rigged etc. The end of the world is prophesised in Armaggedon. It may come true, if enough religious fanatics believe it will come, want it to come, and actively do things to bring it about. But this can happen godlessly. People can bring about fulfillment of prophesies, wittingly or unconsciously, in order to satisfy what is supposedly preordained.
You can't prove a universal negative on something that has no properties or effect on the world. Claims that such a "thing" exists makes the "thing" indistinguishable from being non-existent. Claims that "God" does have an influence on the world are not borne out, if looked at properly.
If prayers are not answered, we can say that it is extremely unlikely that a prayer-answering god exists.
If miracles do not occur, we can say that it is extremely unlikely that a miracle-doing god exists.
If prophesies do not pan out, we can say that it is extremely unlikely that a prophetic god exists.
With imagination, believers can convince themselves that "God" does affect the world and that there is evidence for that. I have not experienced any such things myself, despite looking, and praying.
If some event or property can be adequately explained in more than one way, then we do not have a proof, not unless we have a test which can separate one possible explanation from another, as truth and falsity.
complete absence of unicorns
There is indeed a unicorn. It's the Asian unicorn, or saola. It's very rare so it was only discovered in the 90's.
The saola or Asian unicorn actually is a rather magical creature. It weighs about 200 pounds, it looks rather extraordinary and it was only discovered (by scientists) in the 90's.
Magic uses people's assumptions to astonish them. People tend to think that there aren't huge surprises in the world. "Rational" types especially tend to think this. They don't think large beasts could be in the woods, that they don't know about. The saola violates that assumption.
The saola admittedly does have two horns ... It's a unicorn in an abstract sense: because it's called a unicorn, and because it has the rare and magical nature of a unicorn. It exists and it's abstractly a unicorn.
The unicorn you're talking about, exists in an abstract sense, in people's minds.
Actually the saola is considered one of the most spectacular zoological finds of the 20th century (see the link I gave). And yes it is magical, in the sense that I explained: it violates this common belief that many people have, that our current knowledge is complete. With animals, this translates into the belief that large animals can't be hidden around us.
This belief is especially common among "sensible" and "rational" people. See the Wikipedia article on pseudoskepticism for a reasonably good explanation of this kind of thinking. I put "sensible" and "rational" in quotes because this belief isn't actually sensible or rational. It's a mental shortcut that saves the person the effort of thought, while maintaining an appearance of being sensible and rational. Most of the time, the pseudoskeptic believes implicitly that any claim beyond what is already scientifically established, is false. If you asked them explicitly if they believe this, they would say no. But this assumption is implicit in their thinking.
The actual scientific researchers tend to be more humble and tentative in their beliefs, in their own area of research. They have a feeling for how much is unknown.
Indeed, I have found that less "rationally-oriented" people are more open to the possibility of things unknown. They don't do the mental shortcut "anything beyond what is already scientifically established, is false".