Burden of Proof.

[WordWolf]

From time to time, some of us discuss things.  Some of those times, someone correctly invokes points of logic. Other times, someone INcorrectly invokes points of logic. One of the worst examples of a repeated error involves "Burden of Proof" and "Shifting the Burden of Proof."

So, some basics.

http://rationalwiki.org/wiki/Burden_of_proof

"Burden of proof (also known as onus probandi in Latin) is the obligation on somebody presenting a new idea (a claim) to provide evidence to support its truth (a warrant). Once evidence has been presented, it is up to any opposing "side" to prove the evidence presented is not adequate. Burdens of proof are key to having logically valid statements: if claims were accepted without warrants, then every claim could simultaneously be claimed to be true. "

"If someone has presented you with an idea and says that the burden of proof is on you to disprove the idea, work out what the null hypothesis is and then put their evidence for the idea against it.

The person claiming something is possible or has happened needs to produce evidence to refute the null hypothesis."

"Fallacious shifting of the burden of proof occurs if someone makes a claim that needs justification, then demands that the opponent justify the opposite of the claim. The opponent has no such burden until evidence is presented for the claim. "

 

https://en.wikipedia.org/wiki/Philosophical_burden_of_proof

"One way in which one would attempt to shift the burden of proof is by committing a logical fallacy known as the argument from ignorance. It occurs when either a proposition is assumed to be true because it has not yet been proved false or a proposition is assumed to be false because it has not yet been proved true."

http://rationalwiki.org/wiki/Extraordinary_claims_require_extraordinary_evidence

"

"Extraordinary claims require extraordinary evidence" was a phrase made popular by Carl Sagan. However, Laplace writes: "The weight of evidence for an extraordinary claim must be proportioned to its strangeness."^[1] Also, David Hume wrote in 1748: "A wise man ... proportions his belief to the evidence", and "No testimony is sufficient to establish a miracle, unless the testimony be of such a kind, that its falsehood would be more miraculous than the fact which it endeavors to establish."^[2] and Marcello Truzzi says: "An extraordinary claim requires extraordinary proof."^[3]

Either way, the phrase is central to the scientific method, and a key issue for critical thinking, rational thought and skepticism everywhere.

The evidence put forth by proponents of such things as gods, ghosts, the paranormal, and UFOs is highly questionable at best and offers little in the way of proof. Even if we accepted what evidence there is as valid (and it is highly debatable if we should), limited and weak evidence is not enough to overcome the extraordinary nature of these claims."

"Alice and Bob are two friends talking after school. Alice tells Bob that she watched a movie the previous evening. Bob believes her easily, because he knows that movies exist, that Alice exists, and that Alice is capable and fond of watching movies. If he doubts her, he might ask for a ticket stub or a confirmation from one of her friends. If, however, Alice tells Bob that she flew on a unicorn to a fairy kingdom where she participated in an ambrosia-eating contest, and she produces a professionally-printed contest certificate and a friend who would testify to the events described, Bob would still not be inclined to believe her without strong evidence for the existence of flying unicorns, fairies and ambrosia-eating contests. "

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So, where does the burden of proof lie? With a little practice, this is easy to determine.  Find the original assertive claim.  THAT is the statement that must be proven.  If the supposed "original" claim is SKEPTICAL (it says something DIDN'T happen or is IMPOSSIBLE, for example), then look further back. THAT statement is challenging a preceding statement that something DID happen or CAN happen.   THAT's the claim that needs to be proven.  One does not definitively prove the NON-existence of something-one proves the existence of it. 

Example: A standing claim exists for a town that it was founded in 1491 by Don Rodrigo Diaz de Carreras.  The entire town accepts this as fact.  One day, someone comes along and loudly insists that this can't possibly be true-he was never anywhere NEAR that town!    Who has the Burden of Proof?    Someone claimed once that the person speaking up "first" or "LOUDEST" has the burden of proof. That's never been so.  In this case, the Burden of Proof is on the townsfolk to provide SOME evidence for their claim. Do they have evidence Don Rodrigo was in the area, or documentation of their founding, or some other reason to believe their account other than "we're sure this is right"?   If not, then they failed to meet the burden of proof. It's obvious the town exists, but they can't prove Don Rodrigo founded it.    

It's a separate issue of the new arrival can also provide evidence that the town was founded after Don Rodrigo's death and he was never on that continent, but that's not necessary under the burden of proof.   If they want to consider that SEPERATELY ("The town was founded by COLUMBUS in 1942"), then that's a different question and now a different burden of proof must be met.

 

Really, this isn't hard.

 

 

 

 

[Rocky]

Hopefully (and if the town has had the services of a credible historian) the town would already have some evidence to back up the claim that Don Rodrigo founded it, when he founded it, and who he was anyway.

If that's that case, then wouldn't the person attempting to refute the professed history of the town have the burden of proof to reasonably challenge the previously accepted history of the town?

I'm not really challenging your example, just suggesting that the town's burden should already have been established and fulfilled.

[Raf]

You mean like everyone knows Rome was founded by Romulus and Remus?

[Raf]

I can already see how exactly one line from WW's post will be exalted as the rest is ignored.

[Longhunter]

Establishing the null hypothesis is important when determining who has the burden of proof when addressing pre-existing claims or historically accepted. 

This is why the null hypothesis is important:
1. It can be falsified
 (Validation is less useful because "consistent with" doesn't tell you anything about the the accuracy of the given came.)
2. You don't accept conflicting claims on the outset.
3. You can't prove a negative
 

[Bolshevik]

So this outsider comes and attacks a community's identity and tells them the burden of proof is on them.

I can see the pitch forks . . . "here's your proof"

 

 

[WordWolf]

7 hours ago, Bolshevik said:

So this outsider comes and attacks a community's identity and tells them the burden of proof is on them.

I can see the pitch forks . . . "here's your proof"

 

 

There's TACT and there's TRUTH.  They don't ALWAYS get along.   In this HYPOTHETICAL case presented to illustrate the point, the outsider was more concerned about truth than tact.  That may or may not be wise for him in the practical sense of "will the townsfolk ignore his point despite it being correct" or "will the townsfolk turn hostile in response."

[chockfull]