Burden of proof

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{{cquote|These guys [[Pseudoscience|wanna play]] in the realm of [[science]]. They wanna claim, "We have ''evidence'' for our beliefs!" Ok — what is it?|||[[Michael Shermer]]<ref name="P&T">''[[Penn & Teller: Bullshit!]]'', S02E01, ''The Bible - Fact or Fiction''</ref>}}
'''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 [[Logical validity|logically valid]] statements: if claims were accepted without warrants, then every claim could simultaneously be claimed to be true.

==Null hypothesis==
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.

If they have considerable and well-tested evidence, the burden of proof may reasonably be considered to be on the person claiming that the evidence does not hold.

==Science==
In a [[science|scientific]] context evidence is experimental or empirical data (although in some branches, well thought out mathematics may suffice). For example, in identifying a [[chemistry|chemical]] compound, an analyst may present a [[spectroscopy|spectrum]] to support their hypothesis but a [[peer review|reviewer]] may point out that it is insufficient, explain why by offering an alternative interpretation and state that more data is needed, usually suggesting specific data that would be required. This sort of procedure happens constantly in the [[scientific method]], repeating until everyone is happy (or at least until a [[Scientific consensus]] is reached) that the data and explanation match.

=="New" idea==
A burden of proof is generally (though not always) believed to lie with the person asserting some idea that deviates from the "normal" idea. This is not always true — society's views should not be presumed to be true ''if questioned'', but provide a useful background on which arguments can be made.

[[Debates]] frequently descend into arguments about which side the burden of proof lies with.

[[Denialism|Denialists]] of [[evolution]] and denialists of [[global warming]] have a habit of merely ''ignoring'' evidence and claiming that the burden of proof still rests with the proponents of those concepts.

==Abuse==
[[File:Trump retweets fallaciously.png|thumb|right| Donald Trump shifting the burden of proof.]]
The burden of proof is often abused in [[rhetoric]] and arguments.

===Shifting the burden===
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. This is especially a favourite among pushers of [[unfalsifiable]] claims, most likely because the opposition's inability to prove it wrong subconsciously plants the idea that [[Argument from ignorance|the claim being made has merit]] without ''actually'' having to present any evidence of their own.

===Falsifiability===
{{main|Falsifiability}}
Often, someone will present a new idea and say that it must be accepted because it cannot be ''disproven''. This is insufficient because without supporting evidence, there is no reason to accept an idea, even if there is no contrary evidence. One example is that of a [[simulated reality]], which proposes that the human race does indeed live in ''[[The Matrix]]'' and we are inside a [[computer]] simulation. There is no evidence ''against'' this idea. In fact, it may be impossible to fully disprove. As there is no real evidence for it, however, there is no reason to accept the idea as real. Another famous example is [[Russell's Teapot|the teapot]] proposed by [[Bertrand Russell]], the existence of which cannot be disproven.

===Exceptional claims===
{{main|Extraordinary claims require extraordinary evidence}}
Indeed, if one is making an ''exceptionally'' bold claim (such as with [[alternative medicine]] that claims [[Patent medicine|miraculous cures]]), then exceptional evidence is expected in its support.

===God===
[[File:UnoReverseCard.png|right|thumb|165px|Basically, this.<br/><small>(click to enlarge)</small>]]
Some [[theist]]s maintain that unless [[atheists]] can disprove the existence of a [[god]], or [[gods]], their position is untenable. It does, however, depend on which of the many thousands of humanity's gods one has in mind; strangely, such theists cheerfully accept the arguments against every god except their own preferred one(s).

On similar lines, some [[Antitheism|antitheists]] maintain that because theists cannot prove the existence of their chosen god or gods, their position is untenable. A similar fallacy, from the opposite direction.

The burden of proof lies with whoever is making the assertion. If there's no evidence either way, it's a matter of [[faith]], or lack thereof. Expressing a personal [[belief]]/disbelief in the existence of a certain god/goddess is sound enough, but claiming their opinion is factual or denouncing the opponent's claim as false without any proof supporting one idea or disproving the other is fallacious. While an unfalsifiable claim/[[hypothesis]] can be proven neither right nor wrong, it is reasonable to dismiss it as non-factual if it lacks logical supporting evidence.

==In a nutshell==
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{{#ev:youtube|KayBys8gaJY}}
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==See also==
*[[Argument from incredulity]]
*[[Falsifiability]]
*[[Flying Spaghetti Monster]]
*[[Negative evidence]]
*[[Russell's Teapot]]
*[[Presumption of innocence]]

==External links==
*{{wpa|Burden of proof}}
*[http://www.nizkor.org/features/fallacies/burden-of-proof.html Burden of Proof], [[Nizkor Project]]
*[http://www.infidels.org/news/atheism/logic.html#shifting Shifting the Burden of Proof], [[Secular Web]]
*[http://www.atheistfrontier.com/glossary/love.pl Logical, Objective, Verifiable Evidence (L.O.V.E.)]
*[https://www.youtube.com/watch?v=KayBys8gaJY The burden of proof], [[QualiaSoup]]
*[https://yourlogicalfallacyis.com/burden-of-proof Your logical fallacy is burden of proof], [[YLFI]]

==References==
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[[category:Latin phrases]]
[[category:Philosophy of science]]

Categories: Latin phrases, Philosophy of science