Hilary Putnam has died(dailynous.com)
dailynous.com
Hilary Putnam has died
http://dailynous.com/2016/03/13/hilary-putnam-1929-2016/
55 comments
Does he take for granted that the mind == the brain? Because that seems philosophically tenuous to me.
> For the body-mind interface, if any, is far from simple. Certainly the mind is not the only factor that organizes, unites or directs the body. The body manifests perfection at its conception, and in the days thereafter when it is still a microscopic embryo that could hardly be said to possess a mind its developing blood and immune system also react directly and independently to throw off poisons or diseases without any knowledge or known mental influence. -- Guy Murchie, The Seven Mysteries of Life
We were all doing "intelligent" things well before we had brains...
> For the body-mind interface, if any, is far from simple. Certainly the mind is not the only factor that organizes, unites or directs the body. The body manifests perfection at its conception, and in the days thereafter when it is still a microscopic embryo that could hardly be said to possess a mind its developing blood and immune system also react directly and independently to throw off poisons or diseases without any knowledge or known mental influence. -- Guy Murchie, The Seven Mysteries of Life
We were all doing "intelligent" things well before we had brains...
Seriously?
For what it's worth, the immune system and brain develop more or less concurrently. And have mechanistic similarities at the biochemical level.
For what it's worth, the immune system and brain develop more or less concurrently. And have mechanistic similarities at the biochemical level.
For me at least, Murchie's book was a revelation. I was ignorant of the possibilities he discusses of "movement without muscles, sight without eyes, hearing without ears, smelling without a nose, thirst quenching without drinking, eating without a mouth, digestion without a stomach or excretion, reproduction without sex, thinking without a brain and life without rest, sleep or death."
I don't now feel we are in the position to be drawing philosophical lines around what is the mind, the self, etc, when so much is still unknown.
I don't now feel we are in the position to be drawing philosophical lines around what is the mind, the self, etc, when so much is still unknown.
OK, I'll bite. What moves "without muscles"? Single-celled organisms do, for sure. But the actin-myosin ratchet is a key part of the eukaryotic cytoskeleton that handles movement. The bacterial machinery is more distantly related, but still analogous. Even viruses use analogous machinery.
Greg Egan's Orthogonal trilogy features some amazing single celled organisms :)
Greg Egan's Orthogonal trilogy features some amazing single celled organisms :)
Some examples from the book:
> Below the world of worms and burrowing snails we may consider microscopic creatures like the ameba, who oozes along by pushing out lobes or ruffles of his single cell protoplasm and just flowing into them. His locomotion system (often called "ruffling") was only recently elucidated. It works in each lobe something like an advancing jet of jelly that spreads like the crown of a fountain at its forward end, turning outward in all directions, then back in the form of a surrounding cuff that condenses into a sleeve stiff enough to grip the ground until, turning once more in the rear, it liquefies and pours inward through the center. Biologists used to think that a muscle-like squeezing of the sleeve's protoplasm at the hind end pushed the jelly forward like toothpaste out of its tube, but newer evidence strongly indicates that it is the continuous contraction of the jelly at the forward "fountain zone" (where it turns and stiffens) that literally pulls the central stream steadily ahead. So the consensus of opinion now is that the ameba advances somewhat as does an oriental king, by having his carpet swiftly unrolled before him as he walks, then as nimbly rerolled behind for further unrolling ahead.
> Another method of microbe locomotion, up to several hundred times faster but still slow in human terms, is that of flagella or bacilli with tails. Some of them propel themselves by a recently discovered swivel motion, each flagellum lash rotating freely about its axis like the rigid propeller of a small airplane, generally pulling from the front end and changing course by reversing the direction of rotation. So far as I know, this is the only true wheel motion produced by nature before man invented the wheel about 3500 B.C. and it is powered by the equivalent of a reversible microscopic engine, something technological man has not learned how to make even today.
> A different system again is that adopted by ciliates, common in mud and ponds, whose bodies are covered with thousands of rapidly waving hairs called cilia. Up to 20 times a second each cilium (one thousandth of an inch long) makes its stroke, much like a human swimmer's arm action, first reaching gently forward edgewise for minimum resistance, then sweeping rigidly backward broadside for maximum resistance, the beats coordinated in beautiful rhythmic waves of succession, like pistons in an engine or stalks of wheat blowing in the wind. Even some visible animals use ciliated drive, notably two kinds of comb jellyfish the sizes of a gooseberry and a walnut, and often called respectively the "sea gooseberry" and "sea walnut," each of which has eight longitudinal belts of cilia (coordinated by a special balance organ) that steer and propel it like a spherical Caterpillar tractor.
> Below the world of worms and burrowing snails we may consider microscopic creatures like the ameba, who oozes along by pushing out lobes or ruffles of his single cell protoplasm and just flowing into them. His locomotion system (often called "ruffling") was only recently elucidated. It works in each lobe something like an advancing jet of jelly that spreads like the crown of a fountain at its forward end, turning outward in all directions, then back in the form of a surrounding cuff that condenses into a sleeve stiff enough to grip the ground until, turning once more in the rear, it liquefies and pours inward through the center. Biologists used to think that a muscle-like squeezing of the sleeve's protoplasm at the hind end pushed the jelly forward like toothpaste out of its tube, but newer evidence strongly indicates that it is the continuous contraction of the jelly at the forward "fountain zone" (where it turns and stiffens) that literally pulls the central stream steadily ahead. So the consensus of opinion now is that the ameba advances somewhat as does an oriental king, by having his carpet swiftly unrolled before him as he walks, then as nimbly rerolled behind for further unrolling ahead.
> Another method of microbe locomotion, up to several hundred times faster but still slow in human terms, is that of flagella or bacilli with tails. Some of them propel themselves by a recently discovered swivel motion, each flagellum lash rotating freely about its axis like the rigid propeller of a small airplane, generally pulling from the front end and changing course by reversing the direction of rotation. So far as I know, this is the only true wheel motion produced by nature before man invented the wheel about 3500 B.C. and it is powered by the equivalent of a reversible microscopic engine, something technological man has not learned how to make even today.
> A different system again is that adopted by ciliates, common in mud and ponds, whose bodies are covered with thousands of rapidly waving hairs called cilia. Up to 20 times a second each cilium (one thousandth of an inch long) makes its stroke, much like a human swimmer's arm action, first reaching gently forward edgewise for minimum resistance, then sweeping rigidly backward broadside for maximum resistance, the beats coordinated in beautiful rhythmic waves of succession, like pistons in an engine or stalks of wheat blowing in the wind. Even some visible animals use ciliated drive, notably two kinds of comb jellyfish the sizes of a gooseberry and a walnut, and often called respectively the "sea gooseberry" and "sea walnut," each of which has eight longitudinal belts of cilia (coordinated by a special balance organ) that steer and propel it like a spherical Caterpillar tractor.
OK, but those are all "muscles". They involve the same or similar proteins, organized similarly.
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How is the "Brain in a vat" version different from the Descartes version?
Good question. As far as the thought experiment itself, it's really just a modern phrasing of Descartes' thought experiment. I have no idea if Putnam was even the first to mention a BIV.[0]
The real novelty is Putnam's response, based on the causal theory of reference or content externalism or something like it (I'm fuzzy on this point). I hope I can do it justice from memory.
He argues that because the brain in a vat has never had the appropriate sort of causal contact with external objects, its thoughts don't refer to them. So the brain has whatever brain states go on in me when I think "the sky is blue", but it has never seen the sky, and so its mental states don't refer to the sky. They refer to something else. Probably some disjunctive property of however the apparatus stimulates the brain's nerves (it's really hard to say what this is). It turns out then, that the brain is not falsely believing/failing to know the facts that we might think about by thinking "the sky is blue", it's accurately representing some other kinds of facts. So that type of scepticism is self-undermining, because it attributes thoughts to the BIV that it couldn't possibly have.
I should add that it seems to me that while this argument is tremendously creative, it belongs to a whole strand of philosophy from the 80s that seems to have died out. There's a decent chance you'll read some Putnam, but AFAIK people aren't publishing much on his BIV argument (though people use the example of a brain in a vat sometimes).
[0] Arguably, Descartes posited that the deceiver could deceive you about anything, including logical relations, while the BIV case just involves people giving you misleading sensations, so that's one conceivable difference in the discussions, but that's not a point that I ever saw anyone discuss in detail. It matters for Descartes scholarship, but that's all.
The real novelty is Putnam's response, based on the causal theory of reference or content externalism or something like it (I'm fuzzy on this point). I hope I can do it justice from memory.
He argues that because the brain in a vat has never had the appropriate sort of causal contact with external objects, its thoughts don't refer to them. So the brain has whatever brain states go on in me when I think "the sky is blue", but it has never seen the sky, and so its mental states don't refer to the sky. They refer to something else. Probably some disjunctive property of however the apparatus stimulates the brain's nerves (it's really hard to say what this is). It turns out then, that the brain is not falsely believing/failing to know the facts that we might think about by thinking "the sky is blue", it's accurately representing some other kinds of facts. So that type of scepticism is self-undermining, because it attributes thoughts to the BIV that it couldn't possibly have.
I should add that it seems to me that while this argument is tremendously creative, it belongs to a whole strand of philosophy from the 80s that seems to have died out. There's a decent chance you'll read some Putnam, but AFAIK people aren't publishing much on his BIV argument (though people use the example of a brain in a vat sometimes).
[0] Arguably, Descartes posited that the deceiver could deceive you about anything, including logical relations, while the BIV case just involves people giving you misleading sensations, so that's one conceivable difference in the discussions, but that's not a point that I ever saw anyone discuss in detail. It matters for Descartes scholarship, but that's all.
Here's more about it from an authoritative and amazing free resource, the Stanford Encyclopedia of Philosophy:
http://plato.stanford.edu/entries/skepticism-content-externa...
http://plato.stanford.edu/entries/skepticism-content-externa...
One difference is <s>Putnam concludes you can't tell whether life is an illusion or not</s>, whereas Descartes concludes you can and also god exists. Setupwise it's essentially the same.
EDIT: I got Putnam wrong. There is still the theistic difference though.
EDIT: I got Putnam wrong. There is still the theistic difference though.
That's not right. Putnam's argument is explicitly anti-sceptical. See the Stanford Encyclopedia article linked down thread.
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A little background for the non-philosophers. In the history of Western philosophy, there is a great debate. On one side is the foundational-axiomatic position. According to this general view, philosophy correctly done is like geometry. You start out with a limited set of perfectly clear and absolutely certain concepts and prepositions, and then use these to logically deduct everything important about reality. Major philosophies that assume this include cartesian dualism, materialism, and absolute idealism.
The contrary view is that we can know about reality, but our understandings are always imperfect, including not being able to express everything in a single set of precise concepts. In my view this was Aristotle's overall view, but in any case in the last century and a half, Western philosophy has swung in this direction, including Whitehead, Heidegger, the later Wittgenstein, and all the Pragmatists. Putnam was a leading American philosopher in this anti-foundationalist trend.
Let me add that the foundational-axiomatic position tends to imply that political rule should be by something like a philosopher-king, while I think the anti-foundational one implies liberal democracy.
The contrary view is that we can know about reality, but our understandings are always imperfect, including not being able to express everything in a single set of precise concepts. In my view this was Aristotle's overall view, but in any case in the last century and a half, Western philosophy has swung in this direction, including Whitehead, Heidegger, the later Wittgenstein, and all the Pragmatists. Putnam was a leading American philosopher in this anti-foundationalist trend.
Let me add that the foundational-axiomatic position tends to imply that political rule should be by something like a philosopher-king, while I think the anti-foundational one implies liberal democracy.
Anarcho-capitalists and libertarians of the Austrian School of economics (e.g. those who follow Ludwig von Mises) make a fetish of foundational axioms, yet they are firmly opposed to philosopher-kings.
But they're not exactly fans of modern democracy, either, so it seems that foundational-axiomatic positions do often lead to uncompromising absolutism of one kind or another.
But they're not exactly fans of modern democracy, either, so it seems that foundational-axiomatic positions do often lead to uncompromising absolutism of one kind or another.
"Let me add that the foundational-axiomatic position tends to imply that political rule should be by something like a philosopher-king, while I think the anti-foundational one implies liberal democracy."
Really? That's a very strong statement which I would like to see to be backed up with some axioms. :-) (Because both analytic philosophy and democracy seem more preferable to me.)
Really? That's a very strong statement which I would like to see to be backed up with some axioms. :-) (Because both analytic philosophy and democracy seem more preferable to me.)
A foundational-axiomatic view implies a philosopher king because the vast majority of citizens lack the intellectual ability, much less motivation, to understand it and apply it to political decisions.
Anti-foundationalists, in contrast, think that reality is far too complicated for a single person to figure out, and so we need extended democratic discussion. They also tend to believe that average citizens have a considerable degree of rationality and good motivation, and so can be trusted to be responsible voters. This is, of course, imperfect, but as Churchill famously said, it is better than all the alternatives.
As far as analytic philosophy goes, the classic version is foundationalist-axiomatic, but later versions, such as Strawson, are anti-foundationalist. Later Wittgenstein I think is a mixed case.
Anti-foundationalists, in contrast, think that reality is far too complicated for a single person to figure out, and so we need extended democratic discussion. They also tend to believe that average citizens have a considerable degree of rationality and good motivation, and so can be trusted to be responsible voters. This is, of course, imperfect, but as Churchill famously said, it is better than all the alternatives.
As far as analytic philosophy goes, the classic version is foundationalist-axiomatic, but later versions, such as Strawson, are anti-foundationalist. Later Wittgenstein I think is a mixed case.
Given your observation, I think you might enjoy the book "Soul Machine: the invention of modern mind" by George Makari.
Looks interesting, I'll have to check it out.
> while I think the anti-foundational one implies liberal democracy.
With Heidegger a notable exception.
With Heidegger a notable exception.
I think Heidegger was only partly anti-foundationalist. At the root of foundationalist-axiomatic philosophy is a denial of experienced finitudes in the area of knowledge, and by implication many other aspects of reality. Heidegger starts out affirming experienced finitudes in his phenomenology of human existence, but then abandons it for a supernaturalistic view of human history in terms of race or later cosmos.
A great thinker has passed. One of the great names of 20th century analytical philosophy. They have now all left us, Quine, Rorty, Davidson and now Putnam.
RIP.
I guess they had a similar event on Twin Earth... even though their "water" may be a bit different from our H2O.
I guess they had a similar event on Twin Earth... even though their "water" may be a bit different from our H2O.
Tyler Burge, Kripke, and David Kaplan are still left from the old guard of the golden age of philosophy of language/mind era.
Yes... as is John McDowell, Crispin Wright, John Searle and Alvin Plantinga.
Let's not forget Derek Parfit.
Fodor too.
Kripke is still here. I would add him to that list.
That phrasing is a little unfortunate.
yeah. kripke can be convicted of truly awful exegesis of russell, frege, wittgenstein, but his own contributions to philosophy are mammoth. his attack on the identity of necessary truths and a priori knowledge alone is excellent.
I enjoy reading Kripke and agree he's done solid work. But I must admit I don't get the "Great Philosopher" thing. He did great work in mathematics as a teenager then basically just applied that model root and branch to the philosophical problems his teachers fed him. Which was a perfectly legitimate, even clarifying contribution for the time. But it's not clear to me how the result was a huge advance outside the local Carnapian tradition he was entirely inside of. (And as received a nice documentation in Soames's history of analytic philosophy which uses Kripke as the hero.) Then again I read "Two Dogmas of Empiricism" as almost provincial!
FWIW, I personally find Putnam, Quine, and even Rorty far more interesting to read both now and from a historical perspective.
FWIW, I personally find Putnam, Quine, and even Rorty far more interesting to read both now and from a historical perspective.
i agree on the last point (all 3 more interesting, and i agree with including the 'even'). like i said above though, it's hard to deny that his discussion of contingent a priori as such speaks to kant more directly and strongly than, yeah, "two dogmas of empiricism" (i wasn't impressed either).
to put it another way, i think it would be hard to take many other philosophers as deeply entrenched in a particular set of concerns and assumptions (take, like, derrida or godel) and as effectively press the points of their major work against the work of kant or aristotle or some other towering "we all claim her/him!" figure. "naming and necessity" speaks to kant in terms that need to be answered, which is way more than most publish or perish philosophy professors ever achieve in their lifetime (much less right away, in a lecture presenting a semantics based on modal logic!).
but yeah, the point is well taken. kripke is worth reading once / reading about. putnam is worth reading a lot.
to put it another way, i think it would be hard to take many other philosophers as deeply entrenched in a particular set of concerns and assumptions (take, like, derrida or godel) and as effectively press the points of their major work against the work of kant or aristotle or some other towering "we all claim her/him!" figure. "naming and necessity" speaks to kant in terms that need to be answered, which is way more than most publish or perish philosophy professors ever achieve in their lifetime (much less right away, in a lecture presenting a semantics based on modal logic!).
but yeah, the point is well taken. kripke is worth reading once / reading about. putnam is worth reading a lot.
Yea that's a good point about just how much better (and...different) Kripkes work is than that which has been produced by the publish or perish academic system in philosophy. As far as I can tell it's been utterly counter-productive.
In Kripkes favor I would also add that he was a great stylist, with warmth and humor and...flexibility of presentation. And that partly because of this NN and WRPL are perfect introductory philosophy texts for "generally educated" people. If I taught philosophy instead of working in tech, I'd probably help keep Kripkes legacy alive for that reason alone!
In Kripkes favor I would also add that he was a great stylist, with warmth and humor and...flexibility of presentation. And that partly because of this NN and WRPL are perfect introductory philosophy texts for "generally educated" people. If I taught philosophy instead of working in tech, I'd probably help keep Kripkes legacy alive for that reason alone!
definitely. his warmth and humor are very much on display in "a puzzle about belief" as well:
http://www.uvm.edu/~lderosse/courses/lang/Kripke%281979%29.p...
(putnam is cited in this paper as well, by the by)
http://www.uvm.edu/~lderosse/courses/lang/Kripke%281979%29.p...
(putnam is cited in this paper as well, by the by)
While I would agree that his interpretation of Wittgenstein on following a rule and private language, is wrong as such, i.e. as an interpretation, it is definitely very interesting and thought provoking stuff. It is good philosophy and bears good witness to the creative genius of Kripke.
the stuff he calls the "frege-russel theory of names" is even more egregious than his take on wittgenstein.
to be fair, i don't believe his "take on wittgenstein" is exegetical anyway. he's putting forward his own (interesting!) plus/quus argument. kripkenstein is worth reading in its own right; if you care enough to get wittgenstein right in the first place you shouldn't really be looking to kripke's writing to get there.
and of course, "the frege-russell picture of names" is just a straw man to propel his argument forward in N&N. he's really talking to/about searle there, and most people who are going to read N&N know that. but the stuff he says is still wildly inaccurate if you take it at face value.
(not that frege's views on sense and reference are all that clear in the first place, but they weren't the nonsense that frege (or searle!) attribute to him)
to be fair, i don't believe his "take on wittgenstein" is exegetical anyway. he's putting forward his own (interesting!) plus/quus argument. kripkenstein is worth reading in its own right; if you care enough to get wittgenstein right in the first place you shouldn't really be looking to kripke's writing to get there.
and of course, "the frege-russell picture of names" is just a straw man to propel his argument forward in N&N. he's really talking to/about searle there, and most people who are going to read N&N know that. but the stuff he says is still wildly inaccurate if you take it at face value.
(not that frege's views on sense and reference are all that clear in the first place, but they weren't the nonsense that frege (or searle!) attribute to him)
Most definitely.
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Who stole his ideas from Ruth Barcan Marcus: http://linguafranca.mirror.theinfo.org/Archive/whose.html
if this article makes you think kripke stole the idea of rigid designation, you may as well say he stole it from john stuart mill (or st. augustine, for that matter).
I was very lucky to attend one of Putnam's seminars at Uni abot logic and necessity. His in depth understanding of mathematics, physics, biology and many other sciences made him an almost ideal critic. I was impressed by how, when challenged, he was always able to restate his arguments based on stronger, more fundamental assumption. Putnam is a pleasure to read (which is not always the case when it comes to philosophers) and addresses many of the topics that occasionally come up on hacker news. Can't recommend him enough.
His brain should be preserved in a vat.
Some readers here might be interested in the nice blog he kept last year.
http://putnamphil.blogspot.com/?m=1
http://putnamphil.blogspot.com/?m=1
Better link: https://putnamphil.blogspot.com/
Just wanted to highlight this from the article: "If you would like to make a gift in Hilary’s memory, please donate to Southern Poverty Law Center, 400 Washington Avenue, Montgomery, Alabama 36104."
Just read the name yesterday linked to "trial-and-error predicates" [2], reading on Neural Nets, super-Turing computation and hypercomputation [1].
[1] mentiones nonrecursive sets of numbers, which seems awfully related to a crackpot theory of mine.
[1] https://en.wikipedia.org/wiki/Hypercomputation [2] direkt link from the wiki artikel: https://dx.doi.org/10.2307%2F2270581
[1] mentiones nonrecursive sets of numbers, which seems awfully related to a crackpot theory of mine.
[1] https://en.wikipedia.org/wiki/Hypercomputation [2] direkt link from the wiki artikel: https://dx.doi.org/10.2307%2F2270581
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unlike a lot of contemporaries read through the end of the 20th century / beginning of the 21st, putnam was a rigorous and important philosopher (as opposed to, say, jerry fodor, who should be lauded for generating interest in philosophy and opening new discussions but whose arguments are almost uniformly terrible, technically).
i'd forgotten about his direct realism, but it makes sense given his sort of instinctual bent toward wittgenstein. i wish more analytic philosophers were adventurous enough to reject platonist place-holders and carry their views out to the furthest logical extent.
sorry that this comment was so vague, but what else could it be? just wanted to post that we've lost a great mind.
some random reading in the realm of what i'm talking about:
http://philpapers.org/rec/FINWOR (doesn't mention putnam if i recall, but the wittgensteinian considerations here can shed light on what i'm talking about re: putnam's instincts)
http://ndpr.nd.edu/news/23171-hilary-putnam-pragmatism-and-r... the quick summary of direct realism here corresponds very well with how many of us chicago-wittgensteinians are pulled toward direct realism; once you discard the idea of a correspondence theory of truth and knowledge, and start to recognize that truth conditions are ubiquitously context dependent (in terms of what the speaker is trying to accomplish with the words, the shared cultural knowledge of speaker and listener, etc etc), so too can you get rid of many of the pesky oddities of traditional 20th century analytic philosophy of mind: (abstract?) mental items, qualia (maybe), etc etc. if i see a cow, i don't see "cow + some LaTeX symbol" that exists just-for-me--that's not how language works, and we're not talking about magic observational souls, we're saying that guy over there looked and saw a cow--or whatever we're actually talking about).
anyway, putnam is very worth reading, if only to remember rigor and honesty. as with all philosophy, the conclusions you can take or leave.
i'd forgotten about his direct realism, but it makes sense given his sort of instinctual bent toward wittgenstein. i wish more analytic philosophers were adventurous enough to reject platonist place-holders and carry their views out to the furthest logical extent.
sorry that this comment was so vague, but what else could it be? just wanted to post that we've lost a great mind.
some random reading in the realm of what i'm talking about:
http://philpapers.org/rec/FINWOR (doesn't mention putnam if i recall, but the wittgensteinian considerations here can shed light on what i'm talking about re: putnam's instincts)
http://ndpr.nd.edu/news/23171-hilary-putnam-pragmatism-and-r... the quick summary of direct realism here corresponds very well with how many of us chicago-wittgensteinians are pulled toward direct realism; once you discard the idea of a correspondence theory of truth and knowledge, and start to recognize that truth conditions are ubiquitously context dependent (in terms of what the speaker is trying to accomplish with the words, the shared cultural knowledge of speaker and listener, etc etc), so too can you get rid of many of the pesky oddities of traditional 20th century analytic philosophy of mind: (abstract?) mental items, qualia (maybe), etc etc. if i see a cow, i don't see "cow + some LaTeX symbol" that exists just-for-me--that's not how language works, and we're not talking about magic observational souls, we're saying that guy over there looked and saw a cow--or whatever we're actually talking about).
anyway, putnam is very worth reading, if only to remember rigor and honesty. as with all philosophy, the conclusions you can take or leave.
I was a big fan of 'Meaning and the Moral Sciences.'
Student of Quine, also reddit thread https://en.m.wikipedia.org/wiki/Hilary_Putnam
A was a big fan of 'Meaning and the Moral Sciences.'
The brain-in-a-vat concept was famously used in the The Matrix films.[2]
A summary from Philosophy Index: "The example supposes that a mad scientist has removed your brain, and placed it into a vat of liquid to keep it alive and active. The scientist has also connected your brain to a powerful computer, which sends neurological signals to the brain in the way the brain normally receives them. Thus, the computer is able to send your brain data to fool you into believing that you are still walking around in your body."
"The brain-in-a-vat thought experiment is generally used to ask the question: how do you know that you are not a brain in a vat? The question mirrors an early one from Descartes, which asks how you are to know that there is not an evil demon feeding false information to your senses. The essential conclusion is that, from the perspective of the brain itself, it is impossible to tell whether it is a brain in a vat or a brain in a skull." [1][3]
___________
Links: [1] http://www.philosophy-index.com/putnam/brain-vat/ [2] http://consc.net/papers/matrix.html [3] https://philosophy.as.uky.edu/sites/default/files/Brains%20i...