Posted by
Jack Fisher on Wednesday, June 17, 2009 7:59:04 AM
It's an age-old mantra. You can't prove a negative. Reasonable people engaging in reasonable debates understand this. Irrational people engaging in baseless propaganda do not. Unfortunately, it's the irrational people in power throughout government and religion that abandon reason and spew nonsense to the masses with no basis in fact. This is all well and good in a free society. The problem is, uneducated and uninformed people believe it can lead to destructive policies.
First off, the idea of proving a negative isn't so clear cut. While the mantra is true for the most part, in a strictly philosophical sense it
is in fact possible to prove a negative. But it is only possible when the claim is falsifiable. For instance, if someone asks a random person to prove that there
isn't a rat in their left pocket, the person can prove that by reaching into their pocket and showing that there is nothing there. The claim stated was falsifiable, meaning it could be disproved.
Proving a negative with reason: Evolving Thought
Other claims made in this context are a lot more complicated and more often then not, they are impossible to prove. Many of the claims come across every day and are used as arguments. These include questions such as:
You can't prove Obama's stimulus package
didn't help the economy.
You can't prove banks and customers
didn't know the loans they were giving out were bogus.
You can't prove the drug war
didn't contribute to the violence in Mexico.
You can't prove that god
doesn't exist.
You can't prove that Jesus Christ
wasn't the son of god.
You can't prove creationism
didn't happen.
You can't prove homosexuality
isn't a choice.
You can't prove gay marriage
won't harm society.
You can't prove abortion
isn't murder.
Every one of these claims has the same fallacy. Proving something
isn't present just isn't reasonable. This is because proving negatives require that the entire domain of the argument is understandable, measurable, and verifiable. It must fit the test of falsification. But the breadth of these matters is beyond falsification because it is impossible to verify facts with esoteric and intangible factors.
That is why rational people making rational arguments ask that those making the claim prove it. Their mantra is positive claims require positive evidence (evidence that something is present). Extraordinary claims require extraordinary evidence. Making the claim that a certain bill from the president
did improve the economy can be verified by quantitatively measuring the changes of the economy in conjunction with the changes of the bill and verifying that there was a causal relationship. That is purely reasonable. The problem is, most people in the news and in politics don't do this. Obama famously said "We can't afford to do nothing." It is a negative claim that isn't verifiable, but most people didn't understand that and nothing could be done to stop it.
The same issues emerge in religion. Believers often put the burden of proof on the non-believers, saying they are the ones who have to prove their invisible deity
doesn't exist. But the same fallacy applies. Richard Dawkins made the same argument by claiming you can't prove there
isn't a teapot orbiting the sun. That is why reasonable people say unless you can prove there
is a teapot there, then they don't believe it. It is the believers that are making the claim that there is a deity present, but they offer proof of it. They rely on other fallacies like anecdotal evidence, emotional appeals, and religious texts they allege were divinely inspired. None of this is proof. That is why it is assumed on faith. In a strictly reasonable context, it is impossible to prove any deity. One can only have faith that the deity is there. But too often people equate faith with truth or fact. It isn't. It is an unprovable claim that too many people avoid and pass off as truth and those who do not understand reason are prone to accept it.
Fearmongering, propaganda, and moral panics all emerge from irrational rhetoric. Religion and government use it all the time and so does the media because in many ways, it's easier than checking facts. In a free society people are free to believe, behave, and carry themselves as they wish so long as they do not impose on others. But to defend these freedoms, there needs to be rational policy with reasonable people. So long as religion and government stand in the way, the free society will constantly be challenged. And reason is the best weapon against nonsense.