How should unfalsifiable claims be handled?

Question

Sometimes claims are made that are unfalsifiable. Evidence could conceivably produced to show the claim is true, but no meaningful test could be produced to show the claim is false.

A silly example might be "Are there any white crows?" could easily be proven True if someone found a white crow, but is practically impossible to prove False.

A more real example is Has there been an Encounter of the Third Kind?. It is feasible to prove, with extraordinary evidence, that extra-terrestrials have been in contact with humans, but it is impossible to prove it to be False, even though that is the typical skeptical position.

Another example is about whether governments have broken encryption algorithms. Note: This question does not rely on the supernatural in any way.

A lot of unsupported conspiracy theories thrive on this unfalsifiability.

What should we do with such questions?

• Should they be closed?
• Should they be left open until evidence is found (i.e. presumably forever)?
• Is there an acceptable unreferenced answer that can be provided in these cases?
• Should they be downvoted into oblivion?

Answer 1

Honestly, I think that the accepted answer to "Are yowies real?" likely handles this in the best possible way:

Probably not, but also likely unfalsifiable.

Granted the answer would likely change a bit depending on the question, for example, in the case of the PGP encryption the best answer would be something along the lines of:

There are no known techniques other than a brute force attack; however, if there were they might not be disclosed to the general public.

Truth be told, there are a lot of questions out there - especially if you study history - where the only real accepted answer is you can speculate and provide evidence to back up your conclusions but we may never have a definitive answer or the definitive answer might be years away. I'd say as long as people occasionally check the accepted answers to make sure they are still valid we should be fine.

Answer 2

Here is a proposal. It is based on the example question "Are there any white crows?"

First, I explain the current system, then I propose a new form of acceptable answer.

Acceptable Answers:

Currently, the following are acceptable, in order of preference:

1. Yes, there are white crows. [Ref with examples]

   Assuming it is true, this is the best answer because, hey, we all love being surprised by the world.

2. No, there are no white crows. This was proven by a careful examination of every single crow that is alive. [Ref detailing method of global experiment]

   This answer is unlikely because of the infeasibility, but if it were true, it would be acceptable.

3. Experts have looked for evidence of white crows. They found none. If white crows existed, we would have expected the various bird-watching expeditions to have seen one by now. Absense of evidence where evidence has been predicted is evidence of absense. We should provisionally accept white crows don't exist until evidence turns up to the contrary. [Ref to literature review describing the copious expeditions and the lack of evidence, or to expert declaring that they have been unable to find any literature.]

   This answer is less satisfying because (a) it isn't a 100% definitive answer and (b) it relies on expert opinion. Nonetheless, we have a history of accepting such answers, as they are the best we can expect in the real world. Citing an expert shows it isn't just the answerer's inept Google-searching that failed to find evidence.

4. Leaving the question unanswered.

   We have questions that I expect will never be answered; in theory they are waiting for science to catch up, but science is unlikely to ever achieve that goal.

Unacceptable Answers:

Currently, the following are unacceptable.

• There are no white crows. No-one's ever found one. Trust me.

  This has no references, and cannot be verified. It might be the posted by someone incompetent, a troll, a shill for Big Crow, etc.

• According to my Bayesian model of bird movements and twitcher behaviour, the probability of there being an unseen white crow is 1 in 10,000,000.

  Original research isn't trusted. Mathematical models aren't trusted without a lot of support for the assumptions, premises and the appropriateness of the calculations performed.

New Proposal

None of these answers match the majority view amongst the skeptics. The skeptical position is to provisionally accept that there are no white crows, but to be open to having our mind changed if sufficiently robust evidence was produced.

We should be able to say that. Leaving an obviously false claim unanswered is indistinguishable from us having no position at all, and the question simply being ignored.

I propose that we allow a placeholder answer, copied from a community-approved template.

It would briefly explain (with a FAQ meta-question link for a fuller explanation) that we don't have evidence to prove a claim is false, but the onus is on the claimant to provide empirical evidence that that the claim is true. Until then, we provisionally accept it as false.

The answer should be Community Wiki; no-one deserves real rep for cutting-and-pasting a boiler-plate. Nonetheless, it is likely to be voted up, as people agree that that is their position.

If a counter-answer appears, with evidence, the templated answer is wrong and should be flagged and deleted.

This isn't a great form of answer. I would prefer any of the acceptable answers, above. However, the answer serves to

• explain to the OP and other interested visitors how skepticism works and what the onus is on the believers,
• takes the question off the unanswered list, so the questions that are addressable with research get more attention,
• removes the pressure to close/delete questions that are unfalsifiable, but are still of interest to the Internet.

Answer 3

We do not need to reinvent the wheel here. All that is not falsifiable, is not scientific by definition.

Falsifiability or refutability is the trait of a statement, hypothesis, or theory whereby it can be shown false by way of some conceivable observation practically possible to achieve. In this sense, falsify is synonymous with nullify, meaning not "to commit fraud" but "show to be false".

By the problem of induction, no number of confirming observations can verify a universal generalization, such as All swans are white, yet it is logically possible to falsify it, as by observing a black swan. Thus, the term falsifiability is sometimes synonym to testability. Some statements, such as It will be raining here in one million years, are falsifiable in principle, but not in practice.

The concern with falsifiability gained its great attention by way of philosopher of science Karl Popper's scientific epistemology falsificationism. In this, Popper stresses the problem of demarcation—sorting the scientific from the unscientific—and lays the demarcation criterion falsifibility, such that the unfalsifiable are unscientific, and the practice of declaring an unfalsifiable theory proved true by scientific method is pseudoscience.

http://en.wikipedia.org/wiki/Falsifiability

This doesn't mean "wrong" or "right". It could be either — the problem is that the truth cannot be found though scientific and fact based means, and hence it is not on topic on this site, however interesting or relevant it may seem.

Answer 4

I think the questions themselves should be worded in such a way they can be conclusively answered. This is standard across all StackExchange sites: Questions should fit the Q&A format.

So for example, instead of asking:

• "What proof is there that ghosts aren't real?" or even "Is it true that ghosts exist?"

The question should be:

• "Is there any evidence that ghosts exist?"

The burden of proof should always be on evidence, not on the lack of evidence.

This is similar to not asking overly broad or unanswerable questions on other SE sites (e.g. "What's a good book to learn to program PHP from?" or "What's the best Bruce Willis film?").

So for Have extra-terrestrials ever been in contact with humans?, the question it points to is a great example of asking the same question while making it answerable: Have there been any credible reports of unidentified flying objects?

Likewise, https://skeptics.stackexchange.com/questions/4163/has-pgp-been-broken-by-government-intelligence-agencies would be better asked as, "Is there any evidence that PGP encryption has ever been broken?" (Indeed, that's actually what the accepted answer answers.)

In regards to the "Do white crows exist?" question, I don't think questions like this should be entertained here unless there is a public claim or other disputable evidence for the existence of white crows. So the question should be: "Is there any evidence to back up the claim that white crows exist?" or "Is the evidence for the existence of white crows refutable?".

I would propose that questions framed in such a way that they cannot be answered with evidence are "Pseudo Questions" :)

Answer 5

I feel that those question should be allowed as well. The only real answer to them is "No proof is found of that". It's not perfect, but till it's proven correct, it's considered false.

The only other possible answer I can think of is a speculating/using logic. In lack of better options I think that should be fine.