Probably thanks to Popper, a scientific theory would never be taken seriously if it wasn't as least in some way falsifiable. Without getting into the nitty-gritty of the many theories of justification, (though feel free to do so in an answer), such an idea could contribute to the question of general knowledge, which is typically understood as 'justified true belief', in that a belief that is not falsifiable wouldn't be knowledge (or at least should be accepted as meaningfully true).

Other than tautologies (which includes anything provable by formal logic), are there cases where someone might be justified in meaningfully believing a statement that is non-falsifiable? (I saw meaningfully in light of cases such as this one).

It appears to me that many (even somewhat plausible) metaphysical claims are often non-falsifiable. Does this make them meaningless, or not deserving of belief?

(Somewhat related: this question regarding justification necessary for knowledge)

  • 1
    String theory is seen as non-falsifiable and hence not science by some, but "taken seriously" by others. Your beliefs are primarily a social construct (you believed in atoms because your teacher told you, not because you had direct evidence); falsifiability is rare in your own mind as a precondition to belief. I doubt that in practice you often think "Oh no, I can conceive of no way to prove this wrong, therefore I reject it." You don't have any way to disprove that I have a friend called Steffan who lives in Wales, nor can an experiment prove I love my wife, but it's reasonable believe these.
    – AndrewC
    Commented Jul 20, 2014 at 1:29
  • A scientist being true to empiricism would see believing a particular theory as unhelpful - theories have relative merit according to how closely they fit observed data (which is why Relativity is seen as a better theory than classical Newtonian mechanics). If you go about believing theories you're less likely to spot the new, better one. Many folk I know were put off science because they got tired of teachers telling them what they learned last year was wrong. The mistake was presenting it as fact - it would be better and more scientific to say it's a model we can use.
    – AndrewC
    Commented Jul 20, 2014 at 1:38

4 Answers 4


Poppers criteria is a useful one, but like many criteria operating on the metaphysical field its only a beginning. (I say its metaphysical because is his theory itself falsifiable? It isn't of course, and that should give us pause in denying metaphysics).

Joan Robinson, in The Philosophy of Economics writes:

The hallmark of any metaphysical proposition is that it is not capable of being tested. We cannot say in what respect the world would be different if it were not true, the world would be just the same except we would be making different noise about it. It can never be proved wrong, for it will roll out of every argument on its own circularity; it claims to be true by definition of its own terms. It purports to say something of real life, but we cannot learn nothing from it.

She agrees with Popper, and alludes to him

Adopting Professor Poppers criterion for propositions that belong to the empirical sciences, that they are capable of being falsified by evidence, it is not a scientific proposition.


Yet metaphysical statements are not without content. They express a point of view and formulate feelings which are a guide to conduct.


Metaphysical propositions also provide a quarry from which hypotheses can be drawn. They do not belong to the realm of science but yet are necessary to them. Without them we would not know what it is that we want to know.

She points out

Perhaps the position is different in the respectable sciences [meaning the physical sciences], but so far as the investigations of psychological and social problems are concerned, metaphysics has played an important, perhaps indispensable role.

Since Robinson didn't know the physical sciences - its worth pointing out that the Newtonian conception of space as homogenous, absolute and everywhere the same, sounds quite close to the adoption of a Parmenidian monism in this physical context; and the historical development of atoms (adopted by Newton for his corpuscular theory of light) by Democritus was forced by the challenge that Parmendian monism had on the conventional understanding of change in the world.

Its worth also pointing out that religions, music and the arts are not falsifiable and encode metaphysics; they are meaningful, though not universally so. The correct scientific disposition towards them, is rather than dismissing them out of hand as not encoding verifiable principles; it is to understand their importance - that is anthropology in its widest sense - phenomenological rather than structural.

  • Good, but music an and art do not make claims or statements that one could 'believe' (and I'm not going to comment on justifying religious beliefs). And I'm going to have to read the book you quote, because I had understood economic to make falsifiable claims (it tests its models in similar ways as other sciences, even if such tests must often be done retrospectively)
    – That Guy
    Commented Jul 18, 2014 at 12:17
  • 1
    Sure; but not all knowledge is propositional - recall Wittgensteins notion of private language & Sraffa gesture "Wittgenstein was insisting that a proposition and that which it describes must have the same 'logical form', the same 'logical multiplicity'. Sraffa made a gesture, familiar to Neapolitans as meaning something like disgust or contempt, of brushing the underneath of his chin with an outward sweep of the finger-tips of one hand. And he asked: 'What is the logical form of that?'" Commented Jul 18, 2014 at 12:51
  • Hew, your explanation seems to be convincing at the surface, but I am not able to give you an upper arrow. So Popper, his theory itself remains aloof, but still according him the religion is non-falsifiable same with which he criticized Marxian thoughts. Well... so is Popper a God? I may be ridiculing but may be not.
    – user13955
    Commented Apr 5, 2015 at 4:30

To my mind, questions like this conflate a lot of layers of subtlety, and at the risk of oversimplification, I would like to enumerate a few:

1) One goal of a metaphysics, at least in modern times, is to delineate what is and what is not amenable to materialistic philosophy.

2) The goal of a materialistic philosophy is the reduction of everything amenable to materialism to a collection of sciences.

3) The goal of a science is the reduction of all explanations of certain events to a the predictions of single paradigm.

4) The goal of a paradigm is the reduction of the whole science to 'normal science' (in the sense of Kuhn).

5) Popper's criterion defines what is an acceptable step in the process of 'normal science'.

Each layer here omits a huge range of questions that may be important but are outside the focus of the layer below.

And none of these layers can justify a belief, they simply keep us from mixing different kinds of belief that historically have trouble getting along.

  • Comments are not for extended discussion; this conversation has been moved to chat.
    – stoicfury
    Commented Apr 7, 2015 at 7:05

As Popper pointed out in Chapter I of "Realism and the Aim of Science" justification is impossible, unnecessary and undesirable. If you assess ideas using argument then the arguments have premises and rules of inference and the result of the argument may not be true (or probably true) if the premises and rules of inference are false. You might try to solve this by coming up with a new argument that proves the premises and rules of inference but then you have the same problem with those premises and rules of inference. You might say that some stuff is indubitably true (or probably true), and you can use that as a foundation. But that just means you have cut off a possible avenue of intellectual progress since the foundation can't be explained in terms of anything deeper. And in any case there is nothing that can fill that role. Sense experience won't work since you can misinterpret information from your sense organs, e.g. - optical illusions. Sense organs also fail to record lots of stuff that does exist, e.g. - neutrinos. Scientific instruments aren't infallible either since you can make mistakes in setting them up, in interpreting information from them and so on.

We don't create knowledge (useful or explanatory information) by showing stuff is true or probably true for reasons so how do we create knowledge? We can only create knowledge by finding mistakes in our current ideas and correcting them piecemeal. You notice a problem with your current ideas, propose solutions, criticise the solutions until only one is left and then find a new problem. We shouldn't say that a theory is false because it hasn't been proven because this applies to all theories. Rather, we should look at what problems it aims to solve and ask whether it solves them. We should look at whether it is compatible with other current knowledge and if not try to figure out the best solution. Should the new idea be discarded or the old idea or can some variant of both solve the problem?

There are metaphysical ideas, that is ideas that can't be empirically tested, that solve problems. For example, the idea that it is a good idea to empirically test theories when it is possible to do so, is not empirically testable. You can't specify what would count as a test without an explanation of the merits of testing, so any test would presuppose the idea that testing is worthwhile.


The issue with falsifiability is it seems to be an overwhelming response by misinterpretation.

It begins when you assert that somebody, eons ago, made the specific truth claim that there are no black swans, on evidence.

Now, such a claim wasn't made specifically, it was rather what was thought to be the case, like a tentative view. That probably, there are just white swans. The evidence is that at this point in what we know there are only white swans.

When you realize that even if someone was making specific claims of this type ["There are no black swans. Period."] they had no evidence for it and it was a bare assertion, then there's simply no need for a falsifiability test. In fact, it seems to correlate with the uncertainty principle and a pyrrhonistic skepticism that one cannot know anything. So its basically the idea, without evidence, that you cannot be certain of anything. And you know what. They seem pretty 'certain' about that.

i.e., its all just another front in undercutting the notion that you can know objective reality, that your senses are valid, etc etc. Basically, Kant: that you can't see precisely because you have eyes, that 2+2 is 5, that you can have your cake and eat it too, etc.

  • The falsifiability test is useful: it leads us to actual certain knowledge (though negative).
    – user2953
    Commented Apr 4, 2015 at 7:35
  • It seems to drop the idea of certainty. Which is wrong. So long as you are specific, and treating knowledge as contextual. You can know reality. 2+2 is 4 is true. The standard of 2+2 being 4 is 2 and 2 quantities being 4, reality correspondence theory of truth. 2 and 2 is 4 isn't such because its somehow falsifiable. It has no capacity to be false.
    – ethug
    Commented Apr 4, 2015 at 9:50
  • Concerning the hypothetical claim there are only white swans (stressing it is irrelevant whether someone poses this claim or not), with the falsifiability test we can, if we falsify the claim, gain the knowledge that it is not true that there are only white swans, from which we can deduce there are swans that are not white. So, by falsifying some claim we in fact do gain knowledge.
    – user2953
    Commented Apr 4, 2015 at 9:52
  • 1
    Sure, as in, falsification as in proving false, but that a theory, a theory being something that describes reality, to be true, has to be falsifiable. That's a contradiction. Its not a theory if its false.
    – ethug
    Commented Apr 4, 2015 at 13:56
  • I think we're talking past each other here. I'm talking about your statement "... they had no evidence for it and it was a bare assertion, then there's simply no need for a falsifiability test." - you seem to suggest that a falsifiability test in such situation doesn't add anything. My example shows that it actually can add something, and that whether or not there is evidence is irrelevant for the test to be useful or not.
    – user2953
    Commented Apr 4, 2015 at 13:59

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .