Do you then think it makes sense to consider a possible world where the Earth is a star rather than a planet? — Michael

I'm not sure about the relevance of this question - what does this have to do with rigid designation or naming? (honest question, I really don't understand).

I wrote a post above along those lines -- that rigid designators are akin to signfiers a la Mill's non-connotative proper names, in which they just represent the law of identity of a particular. — numberjohnny5

The importance of Kripke's intervention though (imo) has to do with the way in which he tackles questions of modality - that is, necessity and contingency with respecting to naming. For Kripke, a name is necessary - but this necessity is itself contingent (upon what he calls a primal baptism). It's no accident that Kripke more or less invented modal logic. It's where all the good stuff is.

That's where my disagreement with Kripke begins. I don't think we do, or can, speak literally about different Obamas. There is only one POTUS Obama, and he is not fluent in Mandarin. I believe that when people talk about imagining a counterfactual, they are visualising a world identical to this one except for a few specified differences. — andrewk

Whether you're speaking literally or figuratively here is irrelevant though. As is the talk of 'visualizing'. It's a question of formal identity conditions. Is the identity of thing qua proper name given by a set of descriptive features? Or are descriptive features irrelevant? Kripke affirms the latter, and then offers a reason why: because we can imagine situations in which every descriptive feature of a thing is replaced, and have the proper name still refer to the thing in question (cf. the thought experiment about Godel and Schmitt, which is alot of fun to read about if you're interested). Kripke makes an argument for this in Naming and Necessity, so it's isn't a case of 'interpreting' willy nilly. What Kripke or the normal person 'means' - or even what they think they mean - is not very relevant to the argument at all. Intentionality has got nothing to do with it.

I have no problem with taking it as idiomatic. But maybe it is literal if we take what is - for me - the most intuitive interpretation of the verb 'imagine', which is to visualise an alternative world. That world can be very different, as in a fantasy novel, or it can be almost identical to this one except that POTUS speaks Mandarin. — andrewk

If I may, one way to think about this is to consider what allows you to speak of two worlds with different Obamas in the first place. Kripke's point is that your very ability to speak of two different Obamas, has, as it's prerequisite, the ability to think of an entity designated Obama of whom 'can speak mandarin' can be predicated of (or not) in the first place. That is, you wouldn't even understand what it means to speak of 'two different Obamas' had you not already had some idea of a 'an Obama' which can be in some way different in two different worlds to begin with. Otherwise it wouldn't be two different Obamas, it would be two different people altogether. You wouldn't be able to speak of 'different Obamas'. This is why a proper name is a rigid designator: it designates the same thing in all possible worlds. Your very ability to speak of 'different Obamas' is parasitic on your ability to think a singularly designated Obama who can be different in the first place.

Or another variation: Who or what is different in the different possible worlds? Obama - the singular.

Does one have to subscribe to an essence-based metaphysics in order to make sense of Kripke's approach to counterfactuals? If so then I suppose that leaves me out. I had to give up in believing in essences decades ago when I realised I just couldn't persuade myself any longer that the small, circular, odourless, tasteless wafer at communion really was the bleeding, crucified body of Christ.

If an essentialist approach is not required, then the question remains: what does it mean to say that a human-like organism in another possible world, that shares many of the properties of the BO of this world, is Barack Obama? Or, more crudely, what is the difference between a BO-like organism in an alternative possible world that is BO, and one that is not? — andrewk

Part of your confusion I think stems from treating this as an 'metaphysical' problem. It isn't. Summerised brutally, Kripke's point about rigid designators can be put like this: to the degree that language works as it does, a thing is called what it is because it is called that. Rigid deisgnators are such because they have nothing to do with the 'properties' of the thing in question; this is why it is referred to as an 'anti-descriptivist theory' of naming: no elaboration of the properties of the thing in question can settle why a thing is named as it is. Rather, it is a matter of language: because language functions in this stupid, tautological manner (in which a thing is called what it is because it is called that), rigid designators mark the same thing in all possible worlds.

So I'm confused as to why you used quantum theory as an example of the "last refuge" of the theologian. Because it's not really the case that (serious) theologians (and not your neighborhood evangelical) are shoe-horning God into the picture. It's rather that atheistic (pop-) scientists are shoe-horning atheism into things like the Big Bang, evolution, and quantum mechanics in order to "prove" God does not exist and it's the theologians that have to fight back and explain why it's actually not so black and white. Theologians often get stuck in a kafkatrap. — darthbarracuda

Mmm, I should have qualified - the last refuge within the sciences themselves. Although to be fair, this too overstates the case somewhat. Abiogenesis is another favourite stomping ground of shitty theology, and once again, it's unsurprisingly another site where the scientific work is still underway (although it's made some damn fine strides in the last ten years). The larger point is that religious thinking about science has a tendency to latch on to the uncertainties necessarily latent at the bleeding edge of science, rather than at any point where the scientific work is well established. In every case it's just low hanging, God-of-the-gaps bullshit, a kind of desperation to slot God in to any (rapidly diminishing) space available. A theology with a bit of dignity ought to probably find the divine at work in everything, but then again, the theological engagement with the sciences gave up it's dignity long ago.

I'm not so sure if this is accurate, at least for all theologians. I'm only beginning my study of theology and philosophy of religion, but it seems to me that it is the atheist that commonly begs the question. The point of natural theology is to use empirical observations about the world to make an argument for something that cannot possibly be empirically tested but nevertheless is seen as necessary or important in some way. I don't think the cosmological argument has really been "refuted" by science. Teleology has been shoved aside as reductionist accounts of causality have emerged but it is precisely the latter that depends solely on the material and formal causes and continues to run into difficulties. — darthbarracuda

Frankly, I literally do not care about theology for the most part. In truth, I think the only proper atheistic response to theology ought to be sheer indifference, right up to the point where it starts making claims about naturalism or the sciences. The philosopher Francois Chatelet once spoke of the need for a 'tranquil atheism', one for which "God is not a problem. The non-exis­tence or even the death of God are not problems but rather the conditions one must have already acquired in order to make the true problems surge forth." God is a false problem. I think this is more or less right. Anyone who tries to 'prove God doesn't exist' has already conceded too much to theology - has taken God to be in any way a legitimate problem at all. So I don't much care for those scientists who attempt to shoehorn their atheism into the science either. But once claims are made about naturalism, or about the sciences - or philosophy more generally - which are plainly wrong, misleading, or ignorant, I think that's where one ought to affirm one's atheism by arguing back, at every point.

Not God's 'existence' but his relevance ought to be perpetually put into question - which is why I much prefer 'naturalism' to 'atheism', insofar as the latter is still too oppositionally defined by a relation to the divine. I would prefer simply not to care about the very idea of God, let alone to argue 'against' it.

We expect results from science. When we don't get them, it's probably because we screwed up somewhere and need to re-assess the situation.

We don't necessarily expect results from theology or metaphysics. These two disciplines, in my opinion, are not deserving of the title "discipline" but are nevertheless important (at least the latter is, not sure about theology as I'm leaning towards atheism) as speculative attempts at understanding. — darthbarracuda

I think it's important not to confuse or conflate science with naturalism. If the former refers to a series of methodologically constrained practises of explanatory construction, the latter simply says that our approach to the world ought to take place on grounds that don't appeal to extra-worldly sources or forces. It's possible, in the Quinian mode, to say that these are one and the same thing, but I think it is both possible and desirable to disentangle the two. One can be a speculative naturalist without, for all that, simply falling into the black hole of scientism.

So I don't have a problem with theology just because it is 'metaphysics and not science'. I do have a problem with sloppy distinctions that are illegitimately posed on some a priori, unargued for basis, as when science is somehow disqualified - by sheer power of fiat - from having anything of value to say about the coming-into-being of order. Not only is there no basis for it at the level of principles, it is also simply wrong at the level of fact as well. It has nothing going for it.

It doesn't help either that the constant and brazenly fallacious appeal-to-ignorance that is the invocation of quantum theory is basically the last refuge of the theological scoundrel, having been driven from literally every single other explanatory level of existence other than where - surprise, surprise - the dark and fuzzy frontier of scientific knowledge lies. There's a reason you don't get religious kooks barking shrill over the divine properties of say, silicon chip engineering. At some point, apparently, the perpetual embarrassment tips over into shame.

Well, I don't think it succeeds in so doing, I think it looks a lot less likely to be able to do that now, than it did at the beginning of the 20th Century. I mean, have a look into all the interminable debates on the 'many worlds interpretation' - there you have version of 'naturalism' that has to invoke infinite parallel dimensions, in order to preserve the purported reality of the objects of observation. — Wayfarer

Frankly, the 'interminable debates' on quantum theory - itself a tiny sliver of the unquantifiable success of naturalist approaches to nature - has got nothing on the millennia of theological wrangling over the nature of God. If the less-than-century year old debate over this disqualifies naturalism as a viable position, then theology ought to be once and for all confined not simply to the trashcan of history but it's landfill.

Given order, then something can emerge - triangles will do as an example - but I don't think you're presenting why order should emerge. Nor would I expect an explanation of that, I don't think it is something that can be explained. Naturalism assumes order, or takes it for granted - once it begins to try and explain that order, then it's dealing with a problem of a different kind. — Wayfarer

But this is just wrong - both at the level of facts and definitions. The whole point of naturalism is to abjure transcendent explanations such that the universe can be explained immanently, on it's own grounds, without appeal to the super-natural. The entire idea is not to 'take anything for granted', including and especially 'order'. And this is cashed out in the actual science of things, which, since the discovery of far-from-equilibrium thermodynamics in the mid to late twentieth century, has done pretty much done nothing but demonstrate time and time again, in different fields across different domains, exactly how 'order arises from chaos'.

You attempt to invoke a 'difference in kind' is simply a projection aimed at securing a little piece of the divine for yourself by means of sheer fiat; it exists only as an imaginary line to stave off the real encroachment of naturalism upon a sphere you simply don't want it to cross. But there's no logical reason to draw any such line, except as a theological desideratum motivated more by fear than by facts.

Doneski.

A philosophic theory is a developed question, and nothing other. By itself, in itself, it consists not in resolving a problem, but in developing to its limit the necessary implications of a formulated question. It shows us what things are, what they would have to be, supposing that the question is a good and rigorous one. To place in question means to subordinate, to submit things to the question in such a way that, in this constrained and forced submission, they reveal an essence, a nature. To criticize the question means to show under what conditions it is possible and well-posed, that is, how things would not be what they are if the question were not posed in that way. Which is to say... there is no critique of solutions, but only a critique of problems.

- Gilles Deleuze, Empiricism and Subjectivity

Daniel W. Smith - Essays on Deleuze

May or may not be my last Deleuze reading for a while, unless I decide to pursue a Logic of Sense reading project, which is not altogether unlikely.

Interestingly though, the claim that God is Being has tended to hew worryingly close to atheism itself, insofar as the difference in kind from God to His creation becomes threatened by any such affirmation. It's possible, of course, to create finer and finer distinctions like one between, say, Being and Existence, but then you revert to being caught up again in the problems that the identity of God and Being is meant to solve: precisely how God is meant to relate to the rest of creation. So the God=Being thesis has always had to proceed very carefully, and has generally turned around the rather esoteric theses regarding the various types of 'distinction' advanced by different mediaeval theologians. Thus the Scholastic literature is littered with debates regarding God's 'numerical', 'formal', 'real', or 'analogical' distinction from creation (among others), and all of which tends to runs rings around itself trying to hold on to two ends of a chain that spans from God to Creation.

Thus you have, for example, Nicholas of Cusa's delightful affirmation that: "The absolute maximum [God] is a 'this' in such a way that it is all things, and it is all things in such a way that it is none of them." Or Catherine of Sinea's well known divine revelation that for God: “Just as the fish is in the sea and the sea in the fish, so am I in the soul and the soul in me". These kinds of ambiguities will generally be seized upon and sharpened into mysticism and negative theology on the one hand (Eckhart, where God's relation to Creation becomes entirely negative and undefinable), or a kind of pantheism on the other (Spinoza, Duns Scotus, where the relation is one of strong identity). Its a wonderful and rich history, much of it trying to respond in different ways to the ways in which God can relate to Creation without simply dissolving Him into it. Basically, while the identity of God and Being does 'solve' certain theological problems, it tends to actually open up a whole host of new ones.

A universal Turing machine just is a system that evolves through state space. Or better, it simulates (computes) by means of its sequential progression through such a space, which is itself generally programmed beforehand through transformation rules provided by a set of algorithms. The question - and I'm channelling the biologist Robert Rosen here - is whether or not this type of system has a rich enough 'entailment structure' to model the world in it's entirety. That is, can such a system interact with both itself and the environment in all the ways that systems in nature itself can?

Answering this question requires a pretty close analysis of how causality is encoded or modeled in state systems, but there are pretty great arguments against answering in the affirmative. Hence Rosen's conclusion regarding such enterprises: "[Computable systems] are indeed infinitely feeble in terms of entailment. As such, they are excessively nongeneric, infinitely atypical of mathematical (inferential) systems at large, let alone “informal” things like natural languages. Any attempt to objectify all of mathematics by imposing some kind of axiom of constructibility, or by invoking Church’s Thesis only serves to estrange one from mathematics itself." (Rosen, Essays on Life Itself). There's alot of ground to be covered before arriving at this conclusion, but one needs to be at least familiar with the exact manner in which computable systems work before arguing either way. And this before one can even begin to discuss questions of truth and so on.

Yes; but, you're asking me how does this forum exist. I'm just saying that it exists in logical space or if you prefer 'state-space'. It could be that I require further education on the matter; but, it seems to me as if you're asking something akin to 'How does the logical symbol ~(not) exist'?

I can't prove its existence; but, merely show it to you in action. — Question

No, I'm not asking that (I have no idea where you even pulled that from?), and no, I don't simply 'prefer' the term state-space, insofar as state space is not 'logical space'. I'm asking you to demonstrate that you know what you're talking about with respect to computability before you start to talk about truth, which you do not seem to be able to do.

I am no computer science expert or know all that much about computer architecture; but, what I do know about computational entities is that they are real in logical space. They exist as true or false entities in the logical space that computers recreate. See, this forum is a kind of logical space. We don't need to know how a TV works to be able to enjoy television. — Question

I don't understand what you mean by a 'computational entity'. And while 'logical space' has a close analog in the notion of state-space, which can be employed in talking about computability, the two are not the same, and the way you employ the term - especially with respect to 'true and false entities', seems to have nothing to do with the latter. I think you seem to be stuck on this idea of 'computability' without really knowing what it actually is.

Again, computability doesn't mean just 'can be replicated inside a computer', which is a vague and imprecise statement. Computers do their computations in specific ways, and to claim computability is to claim that those specific ways and not others can model natural systems in their entirety. If you can't flesh out what those specific ways are, and why they matter - if you don't understand the mechanisms by which computability functions - then you can't even begin to mount a discussion of truth and validity. You keep wanting to skip meat of it and arrive at the end - but that's cheating.

You need to speak about the how of computability before you ask questions about the scope of it.

Yeah, you need to explain what it means for something to be computable. Generally, this has a very specific meaning, to do with being able to model processes through the iteration of a finite set of algorithms which allows for the transformation of states in time across a system. Even this definition leaves alot to be unpacked, and frankly unless you can really engage with the detail here, there's little discussion to had.

Whenever one believes in a great first principle, one can no longer produce anything but huge sterile dualisms. Philosophers willingly surrender themselves to this and centre their discussions on what should be the first principle (Being, the Ego, the Sensible? ... ). But it is not really worth invoking the concrete richness of the sensible if it is only to make it into an abstract principle. In fact the first principle is always a mask, a simple image. That does not exist, things do not start to move and come alive until the level of the second, third, fourth principle, and these are no longer even principles. Things do not begin to live except in the middle.

- Gilles Deleuze and Claire Parnet, "On the Superiority of Anglo-American Literature", Dialogues II

That's very interesting, but I have a hard time reconciling it with ontological considerations. So if I adopt scientific realism, and I'm wondering about the nature of black holes, then is there something about black holes which can't be known? That we can't say at all what black holes are, independent of our astronomical experiences?

Such that advances in theoretical physics about the interior of black holes will only ever be about black holes in relation to how we humans perceive and think about the world? That there is something apart from that which is what black holes are, but can't be understood by us, or even aliens (based on how the perceive and think), or our machine overlords in the future?

Is the nature of black holes inherently unknowable? — Marchesk

Eh, I got ahead of myself in talking about knowledge here. The thing to note is that perception is one manner - and definitely not the only manner - in which we engage with the world. The case of black holes is exemplary in this regard: we predicted them before we had any evidence of them, and the evidence we do have is 'indirect' (gravitational lensing), such that we can't perceive them 'directly'. Perception is clearly at stake here only in a minor way. So to use some Kantian terminology, perception and knowledge belong to two different 'faculties', and in truth, I moved too quickly in talking about knowledge previously. I ought to have stuck more closely with the theme of perception here.

The point of invoking Kant should have been to affirm his idea that not everything is available to perception, not because there are perceptual qualities beyond our ken (although there are), but that the very idea of perceptual qualities may only make sense to beings who can perceive to begin with at all. Recall that what Kant designates as the noumenon is simply "a thing which is not to be thought as object of the senses", and furthermore that "we cannot assert of sensibility that it is the sole possible kind of intuition.... The concept of a noumenon is thus a merely limiting concept, the function of which is to curb the pretensions of sensibility; and it is therefore only of negative employment... It is bound up with the limitation of sensibility, though it cannot affirm anything positive beyond the field of sensibility." (CPR, B310).

The implication - that I read here anyway - is that if sensibility is cannot be 'the sole possible kind of intuition', there can in fact be other - perhaps non-human - kinds of intuition, giving rise to other forms of knowledge, perhaps specific to beings who have evolved in a different way than us. Alternatively, it may be the case that there as aspects of the world which simply have nothing to do with forms of sensibility at all, and that the very idea of sensibility is relative to certain kinds of beings in the first place.

I read Kant then as something of a naturalist, for whom the whole machinery of the Critiques simply bear upon humans, insofar as we are one particular kind of being in a universe in which we may or may not have come into being at all. This is why says that he simply speaks from 'the human standpoint' (CPR, B42). Anyway, I don't want to make this into an exegesis of Kant, but simply use him to tackle what @dukkha referred to as the problem of 'competing world' (in-itself/for-us). I think Kant muddles up the issue by using this latter terminology (especially the 'thing-in-itself'), but if you take seriously what he says about sensibility in particular, you can properly sort out many of the otherwise weird oscillations between idealism and realism in Kant.

The shoes are not 'in-itself' things to be worn on feet. That's just my interpretation of them. As in, how the world exists 'in-itself' is not dependent on my specific history. So, isn't some sort of indirect realism entailed here? Otherwise you'd have two people directly seeing the shoes in two completely different ways. How would this work? — dukkha

One needs to be very, very careful to distinguish between perception and existence. To say that the world looks or feels or smells the way it does because of one's lived experience is not the same as saying that it exists because of that experience. Perception might well be just a limited, local process that happens for some (living) beings in a vast universe which is otherwise indifferent to perception: things don't necessarily 'really look like' or 'really smell like' anything at all. The smell and appearance of things might be relative to beings for whom smelling and looking is an issue at all (who have evolved the capacity to engage the world in terms of smell, in terms of sight, in terms of touch) outside of which smelling, appearance and texture are meaningless. One imagines that there are other modes of engagement with the world that have nothing at all to do with perception, or nothing to do with (human) perception, as with insects who can 'see' the ultra-violet spectrum of light.

One way to think about this is that there is no 'in-itself' of the world, not because 'everything is relative to perception' (the idealist thesis), but because perception itself is a relative phenomenon. We - living beings - just so happen to be the kind of beings who have developed a capacity called perception, which is one among a myriad of ways with engaging and interacting with the world around us. To say this is not to accede to any kind of idealism, but to acknowledge a kind of humbleness with respect to humanity. We have developed - evolutionarily - a manner of engaging in the universe (called 'perception'), which in no way exhausts the many, myriad, and uncountable manners in which it could be otherwise engaged with. If it is true that we do not perceive the world 'in-itself', this is not because there 'really is' a way in which the world ought to be perceived, but because perception as such, is a limited way of engaging with the world to begin with .

(This by the way is how to understand Kant's distinction between 'discursive' and 'intellectual' intuition: Kant's theory of the in-itself has nothing to do with the vulgar idea that there is a world that is 'beyond' perception in the sense that it has perceptual qualities that we cannot know. Rather, the in-itself is aperceptual, it has qualities which have nothing to do with perception, and that is why it will remain a 'thing-in-itself'. It is not that there are parts of the world that are 'beyond knowledge', as if a superior, non-human, or divine knowledge could grasp it, but that the very idea of knowledge is no longer applicable to certain aspects of the world, that is is a simple 'category error' to say we can know such and such beyond our experience of it. This is why Kant remained an empirical realist no less than he was a 'transcendental idealist').

But even in idealist ontologies, Being is almost never denied to the non-living: the Being of the fire or the hat or the society might be 'mind-like' or 'of mind' (however you want to put it), but that's not the same as saying that buildings (say) simply don't have being at all.

You seem to have misread the context of the quote, which relates to the subject matter of ontology.

By all means, speak about philosophy, but don't make things up about it. If you're going to say that ontology "arises in relation to first-person perspective and experience", this is a fabrication, a lie. It is not true, not in any understanding of the term. Yeah, this 'makes me mad'.

'Thing' is a word that barely belongs in the philosophical lexicon (with the exception perhaps of Heidegger's analysis of the term), so I don't know what you're driving at. And I am unapologetic about my scorn of the intellectual dishonesty and philosophical miseducation of which you sow in spades, no matter how politely or conciliatory. I couldn't care less if you believe in voodoo dolls or the ghost of Christmas past, but if you diminish and cheapen a field I hold dear at every point with your half-truths and philosophy-by-allusion-and-Google-search, you can expect to be called out on it.

Why would one categorise a building as a being? What would the German term have been? And do you think that to demolish a building is to kill it? If it is a being, then the answer would be 'yes'. — Wayfarer

Because anyone with a modicum of philosophical education doesn't equate Being with things that are alive. Cf. Aristotle:

"Substance is thought to belong most obviously to bodies; and so we say that not only animals and plants and their parts are substances, but also natural bodies such as fire and water and earth and everything of the sort, and all things that are either parts of these or composed of these (either of parts or of the whole bodies), e.g. the physical universe and its parts, stars and moon and sun. But whether these alone are substances, or there are also others, or only some of these, or others as well, or none of these but only some other things, are substances, must be considered. Some think the limits of body, i.e. surface, line, point, and unit, are substances, and more so than body or the solid..."

(And to preempt an objection, yes, Aristotle equates substance with Being: "That which is primarily, i.e. not in a qualified sense but without qualification, must be substance." (Metaphysics Bk VII).

Nothing of course, will stop you trying to define being in your own utterly idiosyncratic and historically cockeyed manner, but it'd be nice if you'd at least acknowledge the entirely eccentric nature of your understanding, rather than pass it off as anything close to resembling general knowledge.

Yes, and one you get past primary school grammar lessons, you can read, say, the list of primary questions that the wiki has on the subject, practically none of which has to do with the nature of being as that which "arises in relation to first-person perspective and experience" - which is an absurdly narrow and extremely idiosyncratic take on a subject for which the first person in actual fact is generally not at all in question. If you think every time Plato, Aristotle and Parmenides refer to Being they are referring to some first-person experience, you need to go back to first year philosophy class.

Quine: "A curious thing about the ontological problem is its simplicity. It can be put in three Anglo Saxon monosyllables: "What is there?‟ It can be answered, moreover, in a word— "Everything‟—and everyone will accept this answer as true. However, this is merely to say that there is what there is..."

Heidegger: "A few examples should help. Over there, on the other side of the street, stands the high school building. A being. We can scour every side of the building from the outside, roam through the inside from basement to attic, and note everything that can be found there: hallways, stairs, classrooms, and their furnishings. Everywhere we find beings, and in a very definite order. Where now is the Being of this high school? It is, after all. The building is".

'Ontology' is derived from the Greek verb 'to be', specifically, from the first-person present participle of the verb 'to be' (i.e. 'I am'). — Wayfarer

I don't know why you keep pushing this line which is simply historically and factually incorrect. Read the Parmenides, or Aristotle's Metaphysics: in no sense is the 'first person' at all at stake in these. Hell, read wikipedia or the SEP: no one but you thinks being has anything to do with the first person. Again, this is you pushing factually incorrect agendas on the basis of shoddy scholarship and bald prejudice.

Depends what you mean by ontology - I suspect I mean it differently from you: as I understand it, an ontology (roughly) is an account of what is: to account for something is to explain it's 'features': perhaps it's morphogenesis, perhaps it's behaviour under certain conditions, perhaps it's capacity for instigating further processes, or it's capacity for change; perhaps it's historicity, etc etc. This account - whatever it is - can be qualified as realist or not, but ontology (as I understand it) is not about realism or anti-realism. Plato has an ontology, Leibniz has an ontology, Spinoza has an ontology, and only in some cases does the very question of anti/realism arise, and even then in a kind of supplementary, beside-the-point way.

Ontology, understood in this way, is definitely not the destination, provided that it's clear that I'm not talking about ontology being exhausted by the question of anti/realism, which is a tiny pond in a vast ocean of generally far more interesting philosophy. If you begin from anti/realism, nothing of the essential in ontology is touched upon.

I take it that on the account of realism, X is whatever makes up the world regardless of whether we know or perceive it. That could be ordinary objects, matter, information, math, some neutral stuff, whatever. But typically, it's the stuff of physics.

For idealism, it is either the various experiences we have (or any mind has), or the fundamental categories of thought for Kantians which structure or experiences, such as space and time. — Marchesk

What is your theory of knowledge? What is your theory of perception? What is your theory of experience? Why are you conflating these things?

It's not just defining one's terms though, as if it were a preliminary exercise to the main event: if properly conducted, realism or anti-realism will always necessary 'fall out' of those definitions. If you have a theory of what thought (or X) 'is', your anti/realism will follow (or not - ideally, imo, your X will be the 'kind of thing' which renders the debate moot because thinking in terms of inside/outside, beyond/not-beyond is vulgar, practically childish philosophy, but that's me sneaking in opinions here). Defining your terms is the main event - or at least it should be.

Literally questions about what it is one is talking about when one takes a side either way. If you say: 'all is thought' or 'you can't get outside of thought' or whatever (or even, 'you CAN get outside of thought' or 'you can get beyond mind/sensation/feeling/life/X/take-your-pick) - then literally: what are you talking about? What is thought? (or X?) How does it work? What account can you give of it? And if, in fact, X is supposed to account for things, then in what way, through what mechanisms or what process is it meant to do so? What kind of thing is X such that it can even be spoken about in terms of an inside and an outside to begin with, or a beyond or not-beyond at all? What difference does the difference of 'anti' or 'realism' make? How can one make sense of the difference? If these elementary questions can't be answered, then the whole debate is an empty shell, fury and thunder over nothing. If there is no account of what is at stake, then there is no stake.

Yeah, its one of my favourite scientific experiments: the perceptual world is a significant world. This was basically the founding insight of phenomenology (but of course perception does not exhaust our implication with the world...). But I don't see any reason to draw a line of opposition between cognitive science and philosophy. To treat them as somehow mutually exclusive is an apologia for ignorance at best, a wilful impoverishment of both at worst.

These are awesome questions, but there's alot of presuppositions behind them need to be unpacked, and in some cases, perhaps reworked altogether. As a first clue to where things might be badly put, recall that our sensory world is always - if the science is right - 'cross-modal'. That is, we can't separate out sight, smell, touch, movement and hearing and treat them on their own terms without doing violence to the phenomenology of perception. Perception always occurs in an integrated 'perceptual field' in which all our senses are brought to bear on a particular 'scene'. One way to think about this is to turn around the usual intuition that our senses are individual and 'additive' (perception = sight + smell + movement, etc). Rather, one begins with an integrated perceptual field from which the individual senses can be progressively distinguished (to close one's eyes is to 'subtract' sight from a more originary sensory plenum).

The reason for this is that we are essentially meaning-seeking beings (or rather, 'significance seeking beings'). We perceive not in order to simply see, hear and touch objects, sounds and textures (this is a very abstract way to think about things, despite it being intuitive), but in order to negotiate an environment around which to move, to avoid threats and danger, cultivate safety and food, respond to sadness or joy. In others words we 'see' meanings no less than we see 'things'. It is actaully a relatively poor and impoverished phenomenology to say that we simply see things extended in space that are colored, textured, etc. The senses work instead to give us clues regarding how to 'live', in the most mundane sense of the term: how slowly should I walk across this slippery surface (which is glistening with the sheen and transparency of water)? How should I comport my body to walk this narrow ledge? All perception is interrogative, it has an impetus.

To the degree that we are biological beings, our senses have evolved for our survival (although this does not mean that they are only used for survival), and it's in this context that we must approach perception. And it's in this sense that to 'perceive' is in a large measure to seek out the significance of one's environment, rather than to just see and feel a world of objects laid out in space. So it's not quite right to think about our 'biological sensory organs' in isolation from a integrated field of living as such; nerve optics and so on are the biological mechanisms by which perception takes place, but they do not, on their own, explain perception, an account of which would need to take into account the whole developmental history of a living being in an environment in which it lives. Perception works in the service of significance, not in the service of perceiving 'things'.

Another way to approach this is to think not in terms of 'lines' where (say) vision shoots out into the world or vice versa, but in terms of a perpetual circuit in which both body and world are implicated in with respect to a life as it is lived. Perception is not a matter of registering static images on a silver plate that is the brain, it is a matter of living, of a dynamism in which significance and movement are primary to it's understanding. We do not 'model' the world 'in the brain'; we respond to it by being in it, moving through it, reacting to the significances that it presents to us.

And the cool thing is that this is what the science shows. If you take new born kittens with perfectly working eyes (biologically), but do not give them the chance to move around their environment (so as to integrate movement and the significance of what they see), they remain effectively blind.

Weren't there idealists and skeptics about the external world in ancient Greek, Indian and Chinese philosophy? — Marchesk

Sure, and tellingly, their views tended to be considered rather fringe, to the extent that they challenged not simply 'the external world', but philosophy as such. They generally quite self-consciously sat at the edge of what is considered philosophy, and it's not until Descartes that scepticism finds itself properly allied with 'consciousness' such that the anti/realism debate takes the form it does now. If one tracks the history of terms like appearance, phenomenon, subject, object, or intention, to take some random examples, these often have literally zero to do with our modern sense of 'appearance-for-a-consciousness-or-a-mind-or-subject' or what have you, and generally have to do with (now) obscure understandings of 'Being' for which subjectivity was a frankly trivial issue (in keeping with the Christinization of Aristotle, it is the 'soul' which takes pride of place in those debates). The entire vocabulary by which these debates are played out didn't exist, let alone the problems themselves.

Descartes pretty much fucking murdered anything interesting in philosophy by entirely revamping the scholastic philosophical horizon as part of his general Enlightenment drive, and with it came the floodgates into which anti/realism became a respectable subject of discussion. It's no surprise that along with the Enlightenment came liberal individualism (Locke), and with it, it's attendant obsessions over self-consciousness and subjectivity. Our own obsession with these questions entirely reflects this entirely modern narcissism, and is historically mediated through and through (I mean honestly, it takes an almost inhuman kind of pettiness to even entertain the question 'does the world revolve around (my) experience of it?' - even if to spend the effort answering it in the negative).

And notice too how in these debates, the 'function' of what is being disccused is so little defined that experience, sensation, perception, thought, and mind all basically become synonyms for each other despite despite almost always refering to entirely different things in any serious literature on the subject(s). Literally, no one here tends to care 'what' is it they are talking about: only that, whatever it is, it is Very Important and must be defended against the Other Thing whose functioning is also entirely undiscussed and undisclosed. And I'm somehow the one playing parlour games? Please. The stakes have never been lower than in these kinds of arguments.

Yeah, that's not biased towards your own background, interests and stances. — Terrapin Station

Sure, if my 'background' begins with Plato's doctrine of the Forms and moves forward through the history of philosophy from there.

But if I had to guess reasons for it, I'd guess a variety of them, including (a) that Descartes' Meditations on First Philosophy is typically one of the first things that philosophy students (whether "formal" or self-taught) read that has "mindfnck"/pre-philosophical-paradigm-breaking qualities, (b) that those pre-philosophical-paradigm-breaking qualities make it seductive to present general anti-realism as one's view on philosophy boards, (c) that one hasn't gotten far enough along in one's philosophizing that one realizes that there's no privileged epistemic basis for general anti-realism, and (d) I think that quite a few people are rather ad hoc motivated in seeing a general anti-realism as a support for their religious views/as a counter to what they take as attacks on those religious views sourced in realism. — Terrapin Station

Ironically, I reckon the largest impetus that fuels such debates is nothing less than the spirit of modernity itself, with it's concern over epistemic certainty and the quest for an encyclopaedic grasp of the universe. One imagines a Plato or an Aristotle scratching their head over why in the world this was a problem at all. The modern forms of the anti-realist debate - which tend to turn over the absolute triviality that is consciousness (trivial from the ancient POV anyway) - would be total, absolute anathema to them.

So despite some pretending to be defenders of some long-lost ancient knowledge in the face of the onslaught of the Enlightenment, the concern with anti-realism is exactly co-extensive with it as sheer and utter reaction: it's only with the concern over absolute certainty does mysterianism and anti-realist sentiment gain any traction whatsoever, disfiguring the history of philosophy by transposing it's thoroughly modern concerns onto it and colouring it with a reactionary and regressive nostalgia that wishes for a time that never was. Realists, who tend to be even worse in their ignorance of philosophical history, at least acknowledge the modern providence of their views.

I don't buy any of the following: that in lieu of realism/antirealism being a consequence of other views, it's typically just a nominal difference; that the non-nominal difference is not (an issue of engaging in) "actual ontology"/an issue of addressing what sort of thing we're talking about (a la "what it is") or the "nature of things"; or that a stance on realism/anti-realism amounts to "really arguing for" how that stance can account for (other) things. — Terrapin Station

If one doesn't have an account of individuation or ontogenesis that couples with one's stance on anti/realism, frankly, one ought to count oneself out of the debate.

Come, join, we have cake and beer.

Because literally nothing of philosophical consequence follows if you take a position one way or the other. The whole barren debate turns upon the ontological status of 'things' or 'the world' or whathave you: mind/matter/other? But ontological status is an empty concept without the actual ontology that underlies it; not their 'status' but what is being talked about is what everything turns upon. What even is mind? Or matter? Or better, how do these things - whatever they are - function, how do they work to give rise to the variety of the world about us? And if not mind or matter, in what way would process X (whatever you want) individuate? And how would these processes account for X, Y and Z?

If 'everything is mind' (for example), then what you're really arguing that mind can account for things because mind has the kind of properties, or the kind of qualities that can make good on such an account. What matters is not 'that' it is mind, but how it 'works'. And if you can't explain that, then who cares about your position in the anti/realism debate? The same applies if you want to begin with matter, or anything else whatsoever: what matters is the function, not what you call it, which is a surface effect, a nominal non-question.

Frankly the reason that questions of anti/realism are so prevalent on boards like this is such a 'base' level question that anyone can chip in without having to be all that familiar with more interesting, more involved questions from which anti/realism flows. Insofar as there's any interest in these questions, it's because they flag deeper, underlying questions about the nature of mind, the nature of things, or even truth, if one were to follow Michael, for example. But in and of itself, it's a rather banal triviality that isn't that philosophically interesting (note that I don't say this to 'deflate' the question, but to 'inflate' it far beyond the narrow confines in which is usually resides).

Part of the problem is that neither realism nor idealism ought to be 'starting points': these positions ought to follow (or 'fall out from') from other points of departure, broadly speaking. For @Michael, it's a matter of one's take on truth. For myself, it's a question of ontogenesis. In either case, realism nor idealism are not positions to be argued for 'in themselves', they are derivitive, secondary outcrops of more originary - and far more interesting - philosophical problems. Arguments for either will remined mired in dogmatism to the extent the the stakes upon which they turn are unarticulated.

Taken in itself, the question 'is it all in my/the mind or not' (and variants thereof) is such a terrible question that it barely merits any serious discussion. If there's truth to the deflationary position, it's that trying to tackle the problem of anti/realism 'directly' is indeed a false problem; anti/realism is an answer, a result, not a problem from which answers follow.

2. Transcendental Realism - try to show that realism falls out of an analysis of thought/reason itself. If you can show that the very act of making of an assertion or the asking of a question presupposes realist premises then the idealist is check-mated from the very start! — Aaron R

Pretty much the only way to go about this. The OP's options for response all pretty much begin with 'The world is...' - but forget the world: we can begin and end with thought itself: thought as sheerly 'realist' from the get-go. Idealism is thoughtless about nothing less than thought itself.

Socrates implies that knowing starts with aporia and ends in knowledge and not true opinion, which is what the equally as famous last part of this dialogue discusses. So if I am following Deleuze, true opinions are contingent, it is only through our encounters in the world that we find what we must necessarily know, and it is only be working our way through the math or swimming that we can progress, getting somewhere. — Cavacava

Yeah, exactly: the idea is to recognize the incredibly precarious nature of thought - there is no guarantee that thought will take place: it is only ever takes place under the aegis of an encounter by which it is forced to be exercised according to singular circumstances in singular occasions. Interestingly, Deleuze implies that what is encountered in the Meno (by the boy) is precisely Socrates himself: "Something in the world forces us to think. This something is an object not of recognition but of a fundamental encounter. What is encountered may be Socrates, a temple or a demon. It may be grasped in a range of affective tones: wonder, love, hatred, suffering."

One could say that what Socrates doesn't take into account is his own position as a interlocutor, his own being as one who is encountered, fortuitously, and from which the necessity of thought follows. And there's also a very interesting discussion to be had about the epistemic status of math itself, which is far less ideal that is usually thought - it's no accident, despite it's singularly anomalous appearance in the dialogues - that Socrates has to resort to drawing a geometric figure in order to explain what ought to be ideal. The realm of the sensory cannot be excluded from even math.