THE WORLD IS AN ILLUSION


The world we experience is an illusion created by the brain. It's only a very indirect representation of things as they really are.

 

 

CONTENTS


INTRODUCTION - THE PUZZLES

 

Philosophers have always tried to find out what’s real and true by discovering and stripping away what’s mistaken and apparent. They've asked fundamental questions about reality, and have uncovered ambiguities and contradictions which have given rise to long-standing disagreements. Different philosophers have had different concerns about reality. This essay is about what's puzzled me personally, and how I've organised my ideas about it so far.

 

Our knowledge of the physical world outside our minds ["objective reality"] can only come to us via our own perceptions of it. Those pictures in our minds are clearly a different thing from the world itself. We assume that the two are very intimately related. Indeed, we assume that the world is exactly represented by our perceptions. But this isn't necessarily true. In fact, thought and experiment show that it's far from true. So what is the nature of the real world, and what is the relationship between that world and our perceptions of it?

 

[As I’ve discussed elsewhere, perception is a paradoxical notion that raises questions that haven’t yet been answered. Until they are, we can only discuss this subject with reference to that concept, and that’s what I’ll do in this essay.]

 

Another puzzle: the discoveries of 20th century physics have forced physicists to carefully reconsider their ideas about what is and isn't real. They investigate electrons and protons and other things no one's ever seen. Are these things real, or merely convenient fictions used to describe the results of experiments?

 

When people discuss these matters, they're not usually concerned with the words "real" and "reality", but with the things these words refer to. They're concerned with facts and experiences, rather than with how to describe them. But we can only think and talk about facts and experiences by using words. And when we run into difficulties, it's often very easy to get confused about whether we have a problem or disagreement about the facts and experiences, or merely with the way we're describing them. So before we talk about the actual problems at issue, let's be clear about the meaning of the words we're using.

 

 

THE MEANING OF THE WORD "REAL"

 

We learn the meaning of the word by hearing it applied to all the familiar objects and events of ordinary everyday experience: the objects we see and touch and hear, the properties of these objects, the relationships between them, and the events involving them. And it's applied to everything else our senses perceive, such as light, sound, heat, smells, and the forces of gravity and magnetism.

 

The word evokes the complex of mental associations with all these things. And we abstract from all these associations a concept of what all these things have in common, the idea of being something that exists or occurs, of being something which forms part of our everyday experience.

 

The word gathers much of its meaning from contrast with the nature of imaginary things, and deceptive appearances like reflections and other illusions.

 

 

REALITY AND MYSTICISM

 

We learn the word "real" as children, but the word "reality" is a more grown-up word; it's not used in everyday life. It refers to the idea of all things that exist and all events that occur.

 

We may sometimes be tempted to think that the word "reality" is somehow different from other words, somehow privileged (especially when it's spelt with a capital R), but it isn't. Like other words, it's nothing more than a convenient label for a bundle of mental associations.

 

There's no need to surround this word with mystery. We don't normally use it to refer to anything beyond the range of ordinary human knowledge and understanding and there's no need to confuse ourselves by trying to extend its meaning in that way. [Strange how the word "real" isn't surrounded with mystery. And yet the word "reality" is nothing more than the plural nounal form of this idea.]

 

It's possible that there are things totally out of the reach of human perception and scientific instruments, but if so they are totally beyond human knowledge. There are people who believe that some of these things are [partially and imperfectly] perceivable by media of perception other than the physical senses, and so they think of these "supernatural" things as "real". I think they’re mistaken, and so their ideas don't concern me in my efforts to clarify my own thinking.

 

 

REALITY AND HUMAN PERCEPTION

 

The nature of our experiences could have been quite other than it is

 

Our eyes respond to light, our ears to sound, and our other sense organs to other such "physical stimuli", by sending signals along nerve cells to the brain, where they are processed and generate further [internal] signals, which are accompanied by conscious perceptions.

 

Our mechanisms of perception are the outcome of the accidents of evolution. They could have been quite different. We could have had more or fewer senses, and other animals have evolved with sensitivity to sounds and components of light we can't hear and see. So the range of stimuli to which we’re sensitive, and which are the original source of our experience, could have been different. Furthermore, the way in which our brain organises these signals from our sense organs into recognised patterns could have evolved quite differently. If we had evolved differently, our experiences would have been correspondingly different, and consequently, what we think is the nature of the real world would also be correspondingly different.

 

Everyday objects are not what they appear to be

 

Some examples:

 

We’re all familiar with the illusion of moving images on a TV screen. We know that the screen in fact displays a rapid sequence of stationary pictures - which the brain merges to produce the perception of moving images.

 

A TV screen is made up of hundreds of rows of tiny blue, green and red dots - which can be seen with a magnifying glass. There are no white or yellow dots, and yet the brain processes these blue, green and red dots to produce areas of white and yellow.

 

The observations of experimental physics have shown us that the commonsense world of seeable hearable touchable objects and events is not at all what it appears to be. For example, the objects we see are not "continuous", as they appear, but are in fact almost entirely empty space. [If this is true, why can’t you poke your finger into a rock as easily as into a cloud of smoke? It’s because a solid object is a 3-dimensional structure of sub-microscopic entities held together by strong electromagnetic forces. To penetrate that structure requires enough force to break it apart.]

 

Many of the perceived properties of everyday objects are only fictions created in the mind:

 

Physical stimuli produce nerve signals in the brain that are accompanied by experiences of colour, sound, taste and smell. But familiar objects really have no colour as we see it [not even black and white]; they make no sounds as we hear them; they have no smell or taste as we perceive them. Colour and sound, taste and smell, hot and cold, as we experience them, don’t exist in the physical world. They’re not objective properties of observed things or of the physical stimuli emanating from those things. Nor do they exist in the [physical] brain. They’re nothing more than fictions created in the mind.

 

Nearly all the other perceived properties of material objects, as we perceive them, must also be constructs of the brain - products of the way the brain organises signals from sense organs into recognised patterns. [Although it’s hard to make sense of the idea that length and shape could be anything other than objective properties of the aggregations that we perceive as material objects.]

 

We don't perceive things as they really are

 

So our naive perceptions aren't an accurate picture of the real world. Many of our perceptions are completely illusory. Our experiences are just a convenient but very imperfect representation of what exists in the real world. The relationship between reality and our experience is analogous to the relationships between an actual scene and a photograph of that scene, between a musical performance and a C.D.

 

So our customary concept of reality is a very confused and confusing notion. To reduce this confusion we have to modify our customary concept "real" to recognise the above facts. And in particular, we have to give up one major element of the customary meaning of the word "real" - the idea of contrast with mere appearance. Because deceptive appearances are all we ever perceive.

 

 

REDEFINING THE WORD "REAL"

 

The customary meaning of "real" is the idea of being something that exists or occurs, of being something which forms part of our everyday experience. But as we’ve seen, the things that constitute our experience are in fact nothing more than appearances. So in absolutely rigorous discussion, we have to drop the associations of the word "real" with familiar experiences. We still want a word to refer to the nature of things that actually exist or occur, and for this we want to use the word "real". But when we accept that we can’t directly experience such things, "real" becomes a purely abstract idea.

 

However, we just couldn't cope with the world as effectively as we do if we had to think of it and perceive it as tenuous clouds of mysterious sub-microscopic entities. In everyday life, in the social sciences, in every field other than physics and metaphysics, we're just not concerned with this level of reality, but rather with the sort of reliable appearances which constitute our everyday experience. So here, the customary meaning of the word "real' is still satisfactory, and indeed necessary. We need it to distinguish these reliable appearances from things for whose existence there is no evidence or about who's existence there’s strong conflicting evidence.

 

 

REALITY AND PHYSICS

 

Physics can be regarded as the study of the fundamental elements of reality. Physicists have found that solid objects and liquids consist almost entirely of empty space containing a sparse sprinkling of entities too small to be seen even with the most powerful microscope; indeed their nature is such that they could never be visible.

 

Not only are these entities not directly observable, but unfortunately, what’s known about their nature and behaviour can’t be described in everyday language. It can only be described in the languages of physics and mathematics. And to acquire an adequate understanding of those languages requires above-average special ability and many years of dedicated specialised study.

 

Furthermore, physics doesn’t regard these entities as real but unobservable. Instead, it regards them as nothing more than hypothetical conceptual tools devised to enable them to give the simplest coherent description of all the relevant experimental observations and to make accurate predictions about physical phenomena. The fact is that physicists don’t need any notion of an ultimate physical reality in order to do their work. They only search for a consistent structure of concepts and relationships that fits all the observations they have made so far.

 

How confident can we be about the account of reality that physics has given us? We regard most of the body of well-established scientific knowledge as true and factual. But research always continues in areas of ignorance and doubt. And new research provides new observations and new theoretical considerations. That’s why the concepts and propositions of science are never regarded as certain and final but are always in varying degrees provisional, no matter how generally they apply and no matter for how long they have applied. There is always the possibility of future observations and theoretical considerations inconsistent with current understanding.  

 

Physics gives us the best description of reality which we can ever obtain. But we have to accept that it is [and must always remain] a description in terms of provisional and hypothetical concepts. In accepting this we take a very different attitude to that of everyday commonsense – we give the word "real" a very different meaning.

 

Is the knowledge that physics reveals an objective description of the universe, a description independent of the human mind, waiting for us to discover it? An alternative view seems more reasonable to me, the view of that knowledge as a set of patterns of human ideas imposed by human minds on human experiences of the universe, because these patterns are useful or intellectually satisfying to us.

 

 

OBJECTIVE REALITY

 

But is there a real world underlying the phenomena observed by physicists? 


It’s been argued that belief in such an ultimate underlying reality can’t be justified, because that reality can’t be directly observed; that there’s no justification for beliefs that go beyond the evidence of direct observations. It’s argued that belief in ultimate reality is therefore nothing more than a groundless faith.

 

This claim seems unreasonable to me because we can only make sense of our experiences on the basis of a belief in ultimate reality. Putting it the other way round, we couldn't make sense of our experiences if we believed that there was no such underlying reality. Certain other considerations also seem especially relevant: the way our experience, and our model of reality based on it, enables us to satisfy our needs by providing information about a real world around us; the way we can see that our senses evolved for that purpose; the way other people talk and write in ways consistent with our own experience.

 

 

CONCLUSION

 

The familiar world of everyday experience is an illusion, an appearance created by the brain. What we perceive as the substance of objects and liquids, their colour and sound, their temperature, taste and smell, are not aspects of the real world. They are nothing but a very indirect representation of things as they really are.

 

Physics gives us the best information we have about the reality which gives rise to these experiences but this knowledge will never be able to go beyond provisional descriptions expressed in the abstract languages of physics and mathematics. 

 

These conclusions don't affect our lives in any way, because our lives are entirely concerned with the reliable appearances which constitute our experience. So the customary meaning of the word "real" is still satisfactory, and indeed necessary, for dealing with everyday life.

 

But in rigorous discussion the notion of things which exist or occur becomes a purely abstract idea, so in such discussions we have to give up the major element of the customary meaning of the word "real" – its associations with familiar objects and experiences.

 

© Barry Simons 2022