Take the 2-minute tour ×
Philosophy Stack Exchange is a question and answer site for those interested in logical reasoning. It's 100% free, no registration required.

In terms of science, this claim has a pretty straightforward answer. Evidence is the base of all scientific claims, and without sufficient evidence any knowledge claim is meaningless. However, what are the implications of this idea for other subjects like art, history, ethics, etc.? Do these subjects require the same type of evidence that science does? Clearly, art and ethics, subjects that tend to be highly subjective, don't necessarily require evidence for knowledge claims, do they?

share|improve this question
You'll have to narrow this down a bit. What do you mean by "implications of this quote for other subjects like art, history, ethics, etc."? You seem to suggest that it makes sense that scientific claims (what we might call "facts") ought to be supported by evidence. Are you under the impression that historical facts don't require the same justification? Ethical beliefs in the same way? What about art (where does evidence even come into play there?)? –  stoicfury Sep 5 '12 at 2:53
I edited the description to make it clearer. –  Adi Sep 5 '12 at 2:57
Thanks for your edit. I still fail to see, however, how art makes knowledge claims. I can see how ethics makes knowledge claims, since ethics are relative and based on one's view of the world (their "knowledge"), but then it should face the same criterion for acceptable as scientific facts, no? If you want to say that knowledge should be supported with evidence, this applies to all knowledge, whether it's ethical knowledge, historical knowledge, etc. Art simply doesn't seem to apply, since artists don't typically make knowledge claims with their works... –  stoicfury Sep 5 '12 at 7:23
I find this quote problematic only if it is understood as an epistemic justification. We can't use it to deny the existence or possibility of existence of something, which is how its sometimes erroneously used. For instance, we cannot deny that UFOs have visited Earth, but we have no reason to pay any attention to particular claims if no evidence for these particular claims exists, provided we are interested in knowing the truth of these claims. @stoicfury - Ethics are relative? Hmmm... –  danielm Dec 16 '12 at 14:40
add comment

7 Answers 7

Clearly, art and ethics, subjects that tend to be highly subjective, don't necessarily require evidence for knowledge claims, do they?

Of course they do.

What would it mean to make a claim completely devoid of evidence?

Do you think there is any philosopher who claims that murder is wrong, or that a work of art is beatiful, for no particular reason?

share|improve this answer
fully agree, but I think the question ask more precisely about "the same type of evidence that science does". The question would be better rephrased as "is there a meaning in trying to make a difference between evidence of science and that of art, ethics, ... " don't you think ? interesting question by the way ... @elena answer here would also involve Spinoza or Heraclite for all evidence being that of the nature speaking through our language of differentiation/assimilation ? –  robin girard Sep 25 '12 at 17:19
I disagree. Ethisist would often start with the premise that murder is wrong, and then gather evidence to support their claim. Scientists, on the other hand, are supposed to look at the evidence first, and then arrive to whatever conclusion the evidense would lead them. –  Michael Oct 21 '13 at 13:34
add comment

art and ethics, subjects that tend to be highly subjective,

I agree with Michael D. and I'll go even further : arts and ethics can be philosophical objects, and as so, they are part of a science. You may not consider philosophy a rigourous science, but it is, for its strengh comes from observations, deductions and conclusions. It's not always that simple, but that's how philosophers like Leibniz built their whole theories. Read Spinoza's Ethics or his Theologico-Political Treatise, and see if his conception of politics, religion and moral is asserted without justification.

share|improve this answer
add comment

this is a great first question :) welcome. one of the things about philosophy is it's very hard a lot of the time to empirically test the things philosophers say. Take for example Sartre's thesis that consciousness is a palpable absence: inheriting Husserl's idea of the directed nature of consciousness (that it is only consciousness insofar as it is a consciousness of an other), Sartre proposes that it in itself is a 'nothingness', devoid of content, a 'Pierre who is never there' .. seeing as you characterise evidence as empirical facts, one thing to question would be does it do justice to dismiss this formulation merely because there can be no physical proof to substantiate it?

share|improve this answer
add comment

Every human endeavor is proposed and argued for from everyday reason, in the so-called arts and in so-called religion and in poetry and politics and so in. It makes as much sense to say we take a leap of faith and believe in cause and effect or in facts by a certain community thematization as to say we take a leap and consider some doctrine of revelation in so much as we are granting them a privilege: that of being considered the highest truth about our world.

In the contemporary arts, practically speaking, the ability to argue and present conceptual reasons (the evidence could be what people pay, when people report liking, when they go to see, a work of art, or what they report feeling about it, or many other things)for the merit of one's work is almost the center of gravity and almost art itself: it is equivalent to a science community where the ground of the paradigm is in constant argument and opaque transformation. And it is obvious various religions are contently doing polemics, polemics in everyday speech and advanced theology based on logic, with the post-Enlightenment certainty that it is in a privileged relation to truth as scientific facts, which, after all, are nothing but a kind of dumb pointing from a ground of neutral receptivity to sense-data (i.e. theoria in the mystical, Husserlian sense of pure consciousness) at sense-images that correspond to symbols.

The short answer is, it is not obvious that so-called evidence in the sciences have any special claim to content (just as in the arts we sit before a schemata of symbols called facts and then put together some technological item, a piece of art in the Greek sense, and ask if it is valuable to us, a computer for instance: what good is empty knowledge about causes and effects or blueprints for making things that we don't care about?). We only pretend that they do (have a content as evidence) by convention and long training in everyday life: go to more primordial people, they will not find such ideas valid or true as weighed by their common sense due to the fact they are lodged in a different community of shared belief or relgio, post-Enlightenment modernity is also one such community.

share|improve this answer
add comment

Does Christopher Hitchens' very statement (apparently known as Hitchens' razor) have any evidence to support it? This is doubtful, because it expresses an ought, and we have the naturalistic fallacy telling us that one cannot reason from is to ought. Unless we can provide 'evidence' for ought, upon Hitchens' argument, every single ought can be dismissed 'without evidence'. That includes his own statement!

What does this do to ethics and morality? We must be careful to not appeal to people's feelings or sensations, for those are all is-type statements. In his After Virtue, Alisdair MacIntyre argues that without a telos (final purpose/end goal), morality and ethics collapse into Nietzschean power-plays, sometimes masked by appeals to emotivism. Copying a bit from this answer, MacIntyre says on p53:

Each of the three elements of the scheme—the conception of untutored human nature, the conception of the precepts of rational ethics and the conception of human-nature-as-it-could-be-if-it-realized-its-telos—requires reference to the other two if its status and function are to be intelligible.

If we cannot know man's telos—final purpose—then where does morality get us? Likely toward some covert telos shared by a subset of the population in the form of their competing-but-cooperating desires for power. If 'evidence' is required for knowing anything and this 'evidence' is exclusively of the scientific kind, then there are two options (have I missed any?):

  1. Ethics is meaningless because it isn't based on evidence.
  2. Ethics is built on something other than evidence and must be judged based on something other than evidence.

So I will give a qualified yes to Hitchens' argument: it is true in a way I don't think he intended. I think he meant to say:

That which can be asserted without evidence, can be dismissed without evidence.

This form is fallacious, because it is self-defeating, just like Hume's Fork, which is (arguably?) a similar argument.

share|improve this answer
add comment

In terms of science, this claim has a pretty straightforward answer. Evidence is the base of all scientific claims, and without sufficient evidence any knowledge claim is meaningless. However, what are the implications of this idea for other subjects like art, history, ethics, etc.? Do these subjects require the same type of evidence that science does? Clearly, art and ethics, subjects that tend to be highly subjective, don't necessarily require evidence for knowledge claims, do they?

If a claim is not backed up by some sort of evidence how would people ever convince others that what they say is true? What constitute evidence may differ from one discipline to the other. If I may illustrate my point with a example. A chemist may consider the observation of a chemical reaction as pretty trustworthy source of knowledge in his field and then base his conclusions on this

The ethicist may look at the effect of Nazi morality on 20th century Europe and make his judgement on Nazi morality on that.

Now they both may be perfectly acceptable "evidence" in the broad sense of the word yet the type of evidence a chemist requires to accept a position and what the ethicist require may be of a different sort. My examples may be a bit simplistic but I think they illustrate my point.

It is to me plain that different disciplines may have different methodologies and would in certain cases also operate under different epistemology conditions. The logical positivist does not entertain such ideas. To them the empirical method is the Alpha and the Omega of knowledge and anything that uses different means to uncover truth is meaningless. Everything that does not try and confirm its beliefs under their narrow ideas of what constitutes evidence is also discarded as a matter of principle.

“That which can be asserted without evidence, can be dismissed without evidence.” - Christopher Hitchens

As witty as such a quote surely is does he really think people who believe in God do so without any explanation or evidence as to why it is so? He may think the evidence unconvincing but that does not make it disappear for those who have beliefs contrary to his own.

Also I'm left wondering as to why a person reasons for believing something has any influence on the truth of the claim. If I were to say to you that a voice in my head told me God exist would that have any influence on whether Jesus of Nazareth did in fact rise from the grave? Would this call into question the eyewitness testimony telling us so? Will this really have any influence on anything the Bible claims to be true?


It may just be really hard to try and convince other people of your belief if that is your reason, but still it has nothing to do with the truth of the claim.

share|improve this answer
add comment

If I assert (loudly and honestly) that I just saw a boy run over by a car, should you dismiss it without evidence? Both in its import, and its utterance by another functional human being, presumably the same (or at least similar) in capability in their grasp of reality as you. I think not. It will be up to the rejector to explain how another human being has failed while your grasp of reality has not.

(Note: this answer has been completely edited. Comments below are no longer applicable.)

share|improve this answer
"No scientist has risked his life for a theory" , Mark J? That is just not true. Thanks largely to the investment of religious organisations in suppressing evidence-based critical analysis of knowledge claims, plenty of people practicing empirical science throughout history have been threatened or coerced into silence. Equally, many have risked their lives to stand up for their theories in the face of such oppression (and continue to do so). –  user3142 Feb 12 '13 at 4:04
I am not saying that scientists haven't been threatened by religious officials, but that none have ever offered their life for it. That's a bit bigger commitment than merely practicing science under threat. –  Mark J Feb 13 '13 at 4:24
-1 for "No scientist has risked his life for a theory" and then doubling down on it. Complete conjecture. –  obelia Apr 20 '13 at 21:34
explanation for -1: en.wikipedia.org/wiki/Self-experimentation_in_medicine. This is just medicine. I can pull up physicists and chemists too. –  prash Apr 29 '13 at 21:59
add comment

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.