the fallacy of perception

As organic beings the only way for humans to percieve the world around us is to make sense of it through sight, sound, touch, taste and smell.
We use these sensory organs in order to organise the information of the world around us into a coherent set of images, sounds, etc.
This happens because our brain identifies the signifier (the impulse sent from our eyes to the brain) with the signified (the image that our brian corresponds to that impulse).
Now, as our eyes are not made of glass, we can never be sure if the image our brain corresponds to the information our eye detects is the same as the image that is percieved by the eye, it is entirely possible that the image is an arbitrary one selected by our brain simply to make the outside world seem coherent.
The same is true, i believe, of our other senses.
Does this not throw doubt over the actual state of the world around us, as our only means of percieving it is biological and therefore fallible?
And does this not also throw doubt upon empirical evidence and material proof as a basis for scientific study in general?
the notion that something is true because it can be seen, heard, touched… because it can be percieved in a material sense, is perhaps in error as our only notion of perception is through biological, irrecovably human sensors.
Does this mean that our coherent image of the world around us is potentially false?
As Lacan suggests, that our brain simply makes it appear coherent in order to be succesfully navigated, when in actual fact it may be a great mess of impulses and information that we can never truly percieve or understand.
Any thoughts?

Yes, the world is crazy.

Just like someone’s quote in an earlier post,


Try this one, its pretty ridiculous, I got it from

Now how ridiculous is that?

We know Achilles travelling at his speed will beat the turtle sooner or later.

So how is it that maths can say he wont?

shakes head

maybe, but no it is not false if the image keeps repeting itself. It is then true. its purpose and reasons for its atomic workings is what is unknown

But what specific image do you speak of that may be false?

Is our perception of “everything and everything ever” potentially false? Yes, probably. Humans are professional at erring in “everything and everything ever.”

i dont follow your point

“maybe but it is not false if the image keeps repeating itself”

perhaps you could elaborate?

not neccessarily, what I am trying to convey with my inadequete wordings is that, the topic is very broad, which isn’t neccessarily a bad thing. It is just very open ended, which can actually be a good thing.

i agree it is very broad, but my intention is to consider the difficulty of materiality as a basis for notions of reality and truth.

like Baudrillard’s notion that in the posmodern world there is no longer a real.
however he makes the error of assuming that there was once a real, when from an objective point of view this cannot be verified and is likely that there is not and has never been a real

I could use you in the dualism thread. :wink:

I say there is not only reason to doubt reality, but there is biological basis to doubt our perception of reality from hard science. We already know that our senses are filters, not complete collecters of data. We already know from science that much must be “converted” or represented chemically [our brains], graphically, mathematically, or theoretically to even grasp.

If we did not filter data, and reduce input, our brains would literally cook.

That said, the point above about consistency seemed correct. Whatever our perception is, as long as it is shared and consistent - it would appear then to eminate from a consistent, external reality. To doubt that, would be really crazy. Trusting your senses and mind is not the same as accepting factually they are a perfect mirror of external reality.

Experiences are approximations of reality, I cannot rationally see how this could be otherwise.

“Whatever our perception is, as long as it is shared and consistent - it would appear then to eminate from a consistent, external reality. To doubt that, would be really crazy.”

at the risk of sounding crazy i would go further than this and suggest that not only is an external reality unknowable in a scientific sense, but it is also plausible and likely that it is not concrete or consistent

we know that due to constructs like language being external to the human consciousness that our every perception is ideological and therefore subjective, i.e not concrete aporximations of reality

the probablility of everyone having the same or a similar approximation of this reality is logically extreamely unlikely, as our brains are incapable of communicating perceptions directly, our only means of communication being through language, which is never a true approximation of the function of the mind

therefore our individual perceptions will vary infinately

this is related to the arguement that everyone may see a different colour red. it doesnt matter what colour we see, it matters that we agree that it is red.

i would argue that any reality is so vastly different from our understanding of it that there is no guarentee of a coherent reality beyond our perceptions other than reality as a boiling pot of impulses and imformation.

consider the notion of nothingness for example. we summise that nothingness exists because it is needed as a counterpoint to somethingness, however we are incapable of imagining nothingness. it is both impossible and guarenteed of its existence/nonexistence
the difficulty in understanding things like nothingness lies in our need to creat a rational coherent understanding of a reality that is niether rational nor coherent.

i for one doubt the existence of a consistent external reality. i am more convinced by the idea that it is an incoherant swirling mass of information that is at once undisipherable and neccessary to navigate for survival. it is a wild approximation of everything that is or has ever been, it is everything and nothingness rolled into one, and our sensory functions paint this nice tidy packaged image for us so we dont simply go mad and die.

forgive the incoherent nature of this post as i am still in the process of forming an arguement on this, work in progress and all that.

While it may be false, consider:

Our brains are not a de novo product, but rather an accumulation over millions of years of evolution, so while our sense may indeed be false, it is worth noting that our brain grew into our senses and not the other way 'round.

Indeed, modern psychology has demonstrated that the mind is informed by the sense, and in the absence of sensual information, the mind goes haywire. So, while I think everyone recognizes that our sense may not be trustworthy, it is a folly to then place trust in the mind, which is dependent upon those perhaps-not-trustworthy-senses. Indeed, in doing so, one is adding an extra layer (rather than removing one) in terms of approaching useful understanding. This is a problem that goes back to the pre-socratics, but that doesn’t mean that it ought be embraced.

Furthermore, since the brain is limited by the sense, to postulate an unknowable (and it is, definitionally that) world where our senses are indeed false is to postulate a world we can never know, can never model, can never interact with . . . and therefore, never care about.

So, what use does such a line of thinking have?

Philosophy that seeks to divorce the mind from the senses (and in turn, the physical realm) will, invariably, experience the same fate that the mind, itself, does when robbed of sensual experience: meaningless madness.

its use is that in accepting an absolutely irrational world we can accept that a single objective truth is false and instead advocate a pluraity of knowledge rather than a single dominant discourse.
therefore we can break the universal dominance of a material science.
by the way, the if its unknowable why should we care arguement could also be directed towards the god vs. not god debate, and thats been going for a while

I think that debating god vs. non-god is a silly argument, frankly. I think it is largely an artifact of history. Like mind/body dualism.

Also, I would like to see some evidence supporting this idea of a non-rational world as well as a reasoning behind breaking the dominance of material sciences – they seem to be doing a wonderful job.

If you want to moderate the excesses of positivism or to curb the modernist passion for progress, saying, “The world is irrational! Give up! Progress is an illusion!” seems a terrible way to go about it when the world seems quite rational and their approach seems to be working fairly well.

Far better, it seems to me, would be to suggest an alternate metric for progress or to sugest a new direction to move as opposed to simply rejecting what is present.

It is like most of the secular humanists on this board (and in the real world). So, you aren’t religious (specifically, you aren’t a Christian), great. What are you then? Defining yourself in a negative can be an acceptable starting point but there needs to be some meat on them bones.

Well, seeing things is not having them. Any perception is going to be a function of both the object percieved, and the perciever, true. So there are differences between what we see and what is.
As far as the brain selecting images to make the world coherent, yes it certainly does that. Try looking at the letters in this sentence, without instantly registering what the words mean. I’ve found I cannot. So the brain is doing something in addition to the eyes, no doubt about that either.
But these words really do mean something, after all, so what the brain is adding to vision isn’t necessarily false, and is almost certainly not arbitrary. I believe that we percieve objects directly- when I see a chair, I am seeing the chair, not an image of the chair, or my own idea of the chair, or anything like that. The image is incomplete, and is not a totality of knowledge , but ‘seeing’ doesn’t have to be complete to be direct and accurate.
As far as how this all relates to empiricism, I really couldn’t say. I don’t really see how empiricism can begin without some prior epistemology that answers these questions- hopefully the empiricist has some reason to trust his senses, and has confronted this. I know I have such a reason, which brings me to your final point about materialism.
I do think that pure materialism leads ultimately to general skepticism, for the reasons you’ve described and others. A person can (and should) choose to accept the deliverences of sensation, memory, and reason without any justification at all if they must- the possibility of skepticism is insufficient to change this- but the lack of grounding we feel that is supposed to be there will always be somewhat unsatisfiying to an epistemologist. I do not think that pragmatism is a final answer, but only a methodology. I think the only answer that allows for the possibility of knowledge is that the world and our senses that percieve them were designed to be known, and that the mental is actually more important the the material.

While I agree that there is an integrating element in our brain, which allows letters to be strung together into words and words into sentences, as well as our brain’s ability to make solid guesses and fill in the blanks (such as filling in our blind spot, or allowing us to recognize an object after only having seen a small portion of it), I think that this ability remains dependent on the sense.

Clearly the brain is able to do more than just what the five senses can, otherwise why have a brain? But that doesn’t mean that what the brain does isn’t limited by them. So, while the brain adds meaning, it has to be adding meaning to something. That’s why we go crazy in sensory deprevation tanks, because our brain is trying to integrate nothing, go nuts, and starts inventing things to keep it working.

I agree with everything you said, Xunzian. I would also like to point out that the differences between our perception and reality (the ones we can identify) can almost always justified rationally, even by people who have not experienced those differences themselves.

Very true. It is also worth noting that where redundant senses exist, we can usually double-check the mistake to see what is real.


Brain: Well, that doesn’t make any sense. Hands, check it out!

Fingers: Nope, seems straight on this end!

Brain: My, my . . . what could be going on here . . . Ahhh well, lemme try to hit that rock. Hands and eyes go! Ahh well, a miss. Try again! Yay! We can hunt the fishes now with our spear!

wait thousands of years

Brain: Holy crap! Optical density! Reflection! Refraction! Physics and all that junk! Wow!

So, I think the brain should also serve as an arbiter between the senses and when something disagrees with the (seemingly rational world) the brain percieves to try and reach a reliable conclusion. Given that ability, and people transfering memes/experiences/knowledge/whatever-you-want-to-call-it, there needn’t be a reason why someone need have experienced it themselves to rationalize something.

Heheh, agreed. Only a philosopher could have the hubris to make pronouncements on what the brain ‘should’ be utilized for, eh? : )

so what your saying is that we cannot reject empiricism and material science due to the lack of any real alternative.
(read real as rational = false, there can never and should never be any one single alternative)

ok theres a lot to go through here, but in response to your points:

  1. the suggestion that there is no evidence supporting the idea of a non-rational world as evidence can only verified materially which( in my line of thinking is false). by the same token, as evidence is not a guarantee of actuallity there is doubt over a rational world also.

  2. the material sciences are not doing such a wonderful job. We know that the act of perception is fundemantally ideological as the organs of perception and language are external to ourselves and not of our own making. In advocating a single linear discourse or knowledge at the expense of all other modes of thought this ideological view becomes exclusive, says “this is the way of the world, it is as it appears, and any one who believes otherwise is wrong”. This is knowledge elitism and fundementally oppressive. There is no reason not to accept a plurality of disources, over a single meta-line of real science and history. Foucault for example, suggests how this single strand of knowledge measures itself by what it excludes, e.g the mad, the sick, the criminal: if you do not think like the dominant discourse says then you are wrong, you are sick, you are mad, you need to be fixed!

3.Does the world seem quite rational? only if we assume a simple one, two, three relationship between what is seen and what is percieved by the mind. Lacan has shown how the signifier does not correspond to the signified, there is not simply a transparency of meaning, there is a large amount of resistence in this process, so a signifier will not always find the signified and when it does it will also lead to other connected meanings in the signification chain. For example, imagine the signifier “crying” we know exactly what this is to correspond to, then why is there so many different types of crying associated with this (happy, sad, grieving,joyful, anger), each one can be called upon by the same signifier but mean quite different things. the same is true of the visual signifier, (blue = a colour and also an emotion), if the world is as rational as you suggest, percieved in a transparent two way form by the eyes, ears etc. then why such confusion?

4.again there is no alternate metric system with which to progress. progress is plural and not only material.

  1. i agree the meaning of the words is not arbitrary. nor is the image of the perception impulse captured by the eye. however the rational picture conjured up is likely to be so. why should the letter P form this exact pictorial shape? no reason, it just does. why should the colour red look as it does, because the colour pigment 1.1 (as example, im not sure how the colour spectrum is measured), all that matters is that we agree that 1.1 is called red, the picture conjured by that pigment is arbitrary. Images may be arbitrary beyond our realisation that a build up of space and substance is sharp and therefore dangerous. i think that suggesting that images appear in our mind (which is itself blind and deaf, and relient on external sensors for this image) are as they appear in the imagined picture our mind creates is filled with pitfalls.

  2. understanding the brain as designed to know, as being capable of more than the sum of our five senses plus its unifying function is to suggest that the brain is designed with a purpose in mind, which is fine for the creationist theorists. however there is also a great possiblity that the human brain has evolved to simply muddle along the best it can with the tools available to it. first and foremost the brain is a survival tool and nothing more. it can surely get along just fine as the sum of its senses plus unifying function. some anilmals dont even have the senses that we have and they dont seem too bothered. i must stress that the brain is a biological instrument, fallible and the possibility of percieving everything directly, as if through a windowpane is minimal.

7.the notion of organising seemingly contradictory accounts offered by our eyes and hands into a general rule, ‘refraction’ is an example of the brain performing its unfying function, rationalisation is a survival mechanism, it stops us from going mad.

I hope this is all clear as i fear it may come off as an incoherent mass (such is the difficulty of arguing against perceptual coherency)
Postmodernism has long since killed any notion of truth, i cannot see how modernists, disinfranchised by the postmodern funhouse, can simply dig it up again, dust it off and carry on as if nothing ever happened.

then again i am open to debate and relish the oppertunity of having someone change my mind, else i risk the slip into nihilism that is often the consequence of these lines of thought

Forgive me, the syntax here is unclear. Postmodern, shall we say? :slight_smile: I think you are suggesting that lack of evidence isn’t the same as evidence, correct? Which is true. But, remember that it is only logical to be an agnostic in situations where either outcome is equiprobable. Since we have not managed to see anything to suggest otherwise and we have a good deal of evidence to affirm our stance, I see no reason not to ignore the idea of an alternate world until such a time as it forces itself to be addressed due to a gross flaw I see no reason to change my thinking towards a system that, by all accounts, seems much less useful.

Personally, I am an advocate for curing the sick, making the mad sane, and reforming the criminal. I am an advocate for fixing people. I’m also a raging statist with a huge authoritarian streak, if that makes you feel any better. The cherry on the top would be that I am absolutely OK with a certain degree of elitism. Egalitarianism seems silly when it is patently not true. We can seek to moderate the elitism that is inherent in the system, but I think to try and eliminate it would be folly.

As for material science not doing a wonderful job . . . ummmm, look at your computer, look at planes in the sky, look at nuclear reactors, look at genetically modified organisms, look at the sequenced human genome, ect. In terms of doing what material science does, it is very successful. The flaw between our preception and the reality of the situation doesn’t seem to have had a significant impact there, should such a thing even exist.

While many of these points bring up valid correctives to unrestrained positivism, the first question to ask is: where does this leave us? Next, I would point out that people do seem to be able to function quite rationally and without confusion in the world, and while an individual may become confused for a moment or two, I do not think this is a regular state for humans. While word-games are all well and good, what do they give us? Postmodernism, it always seemed to me, walks into my house, breaks my toaster and then gives me a rubber chicken and says, “Cook with this! HAHAHAHAHAAH!” So then I go out to the store, buy another toaster and carry on with my life leaving the postmodernist sitting in the corner saying, “But . . . I broke your toaster. The rubber chicken, don’t you see? There is no toast!” Likewise with language, it is more than adequate for the task of communincation, unless you start to take it beyond the limits that it indendent while at the same time positing some sort of an individual at the centre of it as being the focus of communication (which I would argue is a fallacy).

Edit: Think of the world like one of those paintings that makes a coherent image from a distant, but when you get up close it looks like a jumbled mess. I would contend that the coherent image is the real point of the painting, and the jumbled mess is just a function of you being out of focus. I think that postmodernism often misfocuses on an issue and then says, “See, it doesn’t make sense!” when it makes perfect sense if you step back (or forward) a few steps.

So, start talking about what uses postmodernism has. It won’t get me to work faster, it won’t aid in moral self-cultivation, ect.

No complaints here, but so what? I am absolutely fine with normative definitions. Even with respect to things that I cannot see, like red/green. I understand that there is a difference there and that I am defective. I am OK with that. Likewise with things like race or money – these are totally arbitrary systems that have been set-up, yet we are greatly affected by them. Here there is a relationship between created and creator where the line gets blurred with respect to time.
And if the image created by the mind is so different from what it out there is such a pitfall, why the agreement? People (unless they are defective in some way) agree on how things appear, and internally we can create agreement between how things look, feel, taste, smell, and hear. While the image may be (strickly speaking) incomplete or wrong, it is more than good enough for our purposes.

I never suggested that the brain was designed in any way. It is merely a survival tool. However, if you look at enzymology, you’ll see that when it is truly important, enzymes will be able to catalyze a reaction at the fastest possible rate. Given the importance of our senses, I see no reason why they wouldn’t have been optimized to the point where any reality that exists beyond their reach really isn’t all that important. And when it becomes important, our senses can be modified to fix that too, like with electron microscopes and telescopes, ect.

I agree completely!

yes progress does put planes in the air, cars on the roads, makes computers work, it also poisons our air, rationalizes genocide (case note: holocaust), it maps out the human genome, which by identifying the smart/strong jeans as biologically inherent finds a scientific reason for hierachy, it legitimates inequality, progress is a wonderfull thing, it moves us towards an ever more sophistocated future, yet it is a terrible thing, at all times brutally oppressive, glossing over a fundementally irrational world in the search for one true knowable knowledge, extingiushing all other discourses as it goes. modernism is theortical imperialism. What does postmodernism give us? for the first time a truly free way in which to interpret the world as it is, wide, varied, fragmented, and due to the limits of human capabilites, unknowable.
you suggest that this line of thinking is not useful. do you not mean it is not profitable? does not contrabute towards meta-narraitves? does not legitimate hierachy? it is useful if only in exposing the relations between knowledge, subjectivity and power.

Of course there is a darkside to technological progress – no sane human being would argue otherwise.

But I don’t think that throwing the baby out with the bathwater is a sound corrective to this problem. How does postmodernism seek to address the pollution caused by technological progress? How does postmodernism seek to eliminate genocide and inequality?

So, there is a relationship between knowledge and power and the subjective nature of those woh hold those two leads to a variety of possibilities, some of them not very nice. How to correct this?

Where are the postmodern automobiles? Where are the postmodern social programs? Where does postmodernism intersect with the world?

In short, how is postmodernism not effectively parodied by Aristophanes’ “The Clouds”? And if there is a sound critique of it dating that far back, why bring it up again?