I asked this in a previous form, but since I asked for a "proof" of mind-independent objects I understandably got few takers.

It appears that ever since the "modern" subjective turn, from Descartes through Locke and Kant, there has been a lingering agnosticism concerning the "real" existence of external or mind-independent objects. Significantly, this was never even an issue for the ancients, though "appearances" were. Even for modern empiricists and positivists it is not the naive "object" that is directly perceived but our "idea" of the object.

Yet science gets on with its business, and even philosophical language seems to fall back on a common-sense ontology, "sense-data" models, or a phenomenology that simply dispenses with the problem.

Due to big gaps in my reading, I am unclear how this problem has been typically treated. What are the most influtential contemporary arguments for a common sense ontology or the existence of mind-independent objects? Or does the matter simply continue in a state of "as if" agnosticism?

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    I don't know enough to feel confident about responding (given my position that we can't tell and it never mattered anyway), but I think the two main ones are pragmatics (we act as if they existed) and consistency (the inter-relationships and stability of sense experience is most parsimoniously explained by an external reality).
    – R. Barzell
    Commented Oct 9, 2015 at 15:31
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    @ R. Barzell "it never mattered anyway" I think you miss the point of one of the most important philosophical matters in the history of philosophy
    – John Am
    Commented Oct 9, 2015 at 16:07
  • @JohnAm Something matters if it will change behavior, and by this definition, ontology doesn't matter. For instance, if I bump my foot on a table, it's the pain that motivates me to act, not some belief about whether the table really exists (whatever that means). In all fairness, my belief that other minds exist motivates my stance towards them (that others can suffer gives weight to consequentialist ethics), so in that sense, ontology matters. However, some philosophers (like Berkeley) have proposed ways in which a idealism need not imply solipsism.
    – R. Barzell
    Commented Oct 9, 2015 at 16:24
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    @R. Barzell Can you affirm logically that other minds exist or you rely on belief and you don't care about the secureness of such a belief? Do you really think the philosophy has often wasted time on silly problems?
    – John Am
    Commented Oct 9, 2015 at 16:31
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    Worrall, the current proponent of structural realism, calls Putnam's no miracles argument the "master argument" for realism courses.washington.edu/phil560/Worrall.pdf He admits though that "representations of ‘the’ NMA as either an attempted deduction or as an unadorned probabilistic argument are... undeniably and straightforwardly invalid... The ‘argument’ should be thought of as doing little more than setting the default position." This "little more" lets him argue "for" realism by arguing that no objection to it is conclusive. But one can make a similar maneuver with solipsism.
    – Conifold
    Commented Oct 10, 2015 at 21:34

3 Answers 3


I consider the success of natural science the strongest argument for the existence of "real" external objects. It is very influential in so far it convinces at least all natural scientists :-)

The results of natural sciences are intersubjectively testable. In general, the experts find consensus whether a scientific claim should be accepted as valid or should be refused. In the domain of experimental physics, measurements of one group must - and can - be confirmed by measurements of other groups.

The most simple explanation for the fitting of the measurements of different groups is the hypothesis that all groups measure properties of the same external objects.

On the other hand, I consider Kant's introduction of the concept "thing-in-it itself", about which we do not know anything, a deep insight and a warning against a naive realism: We measure only what passes the filter of our instruments and we construct our knowledge from this input. Hence our knowledge about the external world is at first restricted in its scope. And secondly, it is branded with the characteristics of our mental capabilities.

  • Again, I don't know who down voted,but this is a good answer, in the broad sense. It's true that this question seems to have been off-loaded onto the "opinions" of scientists, some of whom are positivists, some idealists, most pragmatist. Commented Oct 10, 2015 at 2:09
  • Success of science by itself is not an argument for realism since it can be explained along neo-Kantian or naturalistic lines, there is even scientific anti-realism. The missing piece is something like "it would be a miracle if science could be this successful without latching on to something real", the Putnam's no miracles argument. Unfortunately, NMA is a case of the base rate fallacy, and recourse to the inference to best explanation does not save it, as modern realists like Worrall admit. courses.washington.edu/phil560/Worrall.pdf +1 for the last paragraph.
    – Conifold
    Commented Oct 10, 2015 at 21:47
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    @Conifold Could you please expand a bit: What does neo-Kantianism object against taking the high consensus about measurements of independent groups as an argument for the existence of real external objects? - My answer did not deal with the different question, whether the predictive power of a certain theory is an argument in favour of its truth. Concerning that question I tend to the view that we can never decide that a given scientific theory is true. Best we can do, is to falsify a wrong theory and to state a better hypothesis.
    – Jo Wehler
    Commented Oct 10, 2015 at 22:52
  • Let me give you Quine's version, neo-Kantians (e.g. Friedman) are less cynical. Paraphrasing, I affirm says Quine that things, and less so electrons, really exist. Where "exist" means that we can talk about them, and "really" that we can understand each other talking. Basically, both groups believe that intersubjectivity is established through social practice here, not through correspondence with x out there. Even Kant's things in themselves are realism in name only, for all he lets on about them "they" might as well be Parmenides's One. Non-hollow realism proved hard to defend.
    – Conifold
    Commented Oct 10, 2015 at 23:31
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    @Conifold Please indicate a reference to corresponding papers of Quine and Friedman, thanks.
    – Jo Wehler
    Commented Oct 11, 2015 at 21:52

Here i present a rational dialectical view. i.e. When i watch a painting of course i have an idea of the painting but i know under certain circumstances that this is an objective idea. It corresponds to the painting itself and it is not an idea of an elephant camouflaged as a painting tricking my mind. Of course looking and thinking about the painting does not magically present me the "whole reality" of this painting, but i can study it if i like i.e. the paper, the technique, the meaning, the era everything, and at the end i will know that i study this specific painting objectively and not some hidden elephant like the Kantian thing-in-itself. So here it is:

Considering "external reality of objects" is a bit tricky. External is regarded in opposition with "ourselves"-minds. Reality is ascribed on objects that exist on themselves in contrast with imaginations, some other type of false existence or non-existence. Objects are the things under consideration.

So let's consider an example: I have here in my room a nice drawing above my bed. Is this external object real? I watch it everyday for the last 2 years so it must be real. Is there a possibility i watch an optical illusion for two years and i can also sense the paper etc? Sense and assumption can fool me but let's speculate that i confirm the existence of the object in a rational way. (i bring the poor scientists from the other answer so to make their tests on the painting and on me). So it should be real. On the other hand this painting is a specific object. A lot of people have drawings and have the same type of experience that these objects are real. Of course all these paintings are not the same object. Each of these is a different one. And we all confirm according to our experience tested in a rational way that these objects are real and different.

Now let's consider that I take the painting and shred it to pieces. Is the object of the painting still real? No, now it is a shredded painting. Actually it is a mishmash of colored paper. What happened to the reality of the painting? It no longer exists. I still have a memory of the painting before i shred it to pieces. But from now on, it is no more an external but an internal presentation in my memory of the object before i destroyed it. The reality of the painting object was so fragile that it could stand only a small amount of force before it turns to its opposite. If I come to your house and i brought with me a bulk of shred colored paper and i present it to you and i say "here is a nice painting, i bring it to you as a gift", you will surely suppose that i' m a fool.

Now i have a bulk of paper. Is it real? Yes it is real. What will happen if i burn it, will it still be real? Of course not. The paper is gonna turn to ashes and energy. The paper/object i had has disappeared and is no more real. Now i have to do with the reality of this lump of ash and the heat that diffused in the environment.

So the most influential arguments for the "existence of real external objects" must take into account all aspects of the being. Existence is a dialectical category and is contradicted with non-existence. Worst of all, objects are real and not real at the same time. I'm real as a man but also I'm not really an elephant.

  • I gave an up vote for your effort, but wish you stop down voting all over the place because answers are not your answers. The closest you get to a specific answer is: "arguments for 'existence of real external objects' must take into account all aspects of the being." That's not very helpful. Commented Oct 10, 2015 at 2:21
  • Sorry, you seem to have interrupted my completed comment. That was a fragment. My "permission" is irrelevant. You give no references in your answer. The fate of your "drawing" is a reiteration of Descartes' famous identity of "wax," and your "contradiction of nonexistence" seems like a bad or vague misreading of the early sections of Hegel's "Science of Logic." Your arguments, minus citation, seem to rest on something like your "originality," your "certainty," and your "innate intelligence." Plus, when needed, Wikipedia. Forgive me, this is not a compelling style of argumentation. Commented Oct 10, 2015 at 3:02
  • I am original, certain and innate intelligent. And at the same time i' m not. The same applies to you. You are not always an anti realist, an illusionist, and a person who doesn't know the meaning of the words. Life is simple. It's out there.
    – John Am
    Commented Oct 10, 2015 at 14:57

One of the big issues here is what you consider to be "real" and "external". We have to have some sort of definitions of these terms. You seem to be implying by this that you want to know if objects have existence independent of our own conscious perception of them.

The problem with this is that once you cease to be conscious your perspective ceases--so you have no way of ascertaining the existence of anything. One possible argument would be that there is a point during sleep where we cease to be conscious, yet consciousness is later revived. There is still, however, a continuous experience, and we perceive in the world that this is the result of continuous brain activity even during unconsciousness. Even if we doubted the reality of the brain, we could imagine that a similar process might be at play with our mind--our consciousness "sleeps" and "wakes" but continuous experience marches on.

So if our continuous experience finally ceased, we still have no evidence that there would be the independent existence of anything. We can't because we are confined to our own perspective.

However, given that we cannot perceive anything prior to our continuous experience and we cannot perceive anything following it, our continuous experience is the only reality we know--and it makes sense to treat it as such. Within our continuous experience, we do observe that objects continue on despite our period of unconsciousness, and there is no evidence within our continuous experience that our mind is capable of producing such a vast, complex, and persistent world whole cloth.

Therefore, short of a future revelation from beyond our present continuous experience that gives us reason to doubt the "reality" and "externality" of objects around us, these objects are the most "real" and most "external" things we know.

One could call this pragmatic, but really we have no way of defining anything more real or more external than that which we know.

  • Thanks, don't know who down voted, but I voted back up. Yes, this is somewhat like "object permanence" in child psychology. We learn that objects are "gone" then return, seemingly the same. (Hume might find this a very poor proof.) But it does not seem that anyone really makes such inferences to solve some prior problem with the "given object." It's "just there." You may be right, everyone has pramatically just set the problem aside as useless. Commented Oct 9, 2015 at 15:45
  • @NelsonAlexander For contemporary exploration of similar lines of reasoning, see Jürgen Habermas. Commented Oct 9, 2015 at 15:48
  • @NelsonAlexander Consider one approach people use to challenge the "realness" of reality: the idea that it is all a simulation. The problem is that the simulation is what we are acquainted with as reality, so the world beyond the simulation would be a "meta-reality" not a reality from our perspective. Commented Oct 9, 2015 at 15:52
  • I down voted because this answer don't address a rationalist way of argument, it argues based only in experience and after a lot of unnecessary words it finishes exhausted, with only a mere affirmation in quotation marks of the reality of external objects.
    – John Am
    Commented Oct 9, 2015 at 16:03
  • @JohnAm My answer is not meant to conclude any reality, but instead point out the difficulty in doing so. Rationalism is not explicitly mentioned, but is implied in that one cannot empirically verify the existence of objects. Instead one has to reason that one cannot perceive any other existence. Furthermore, an answer need not be exhaustive; other answers may supplement. Commented Oct 9, 2015 at 16:10

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