Illusion and False Perception
I have proposed a hypothesis that music is a special type of illusion, in particular that it is a glial illusion.
But in this article I want to step back a little and consider what it means to say that something is an illusion, and whether or not it makes sense to say that music is an illusion based on our everyday subjective experience of music and how it affects us.
A simple definition of illusion is that an illusion is a false perception.
To be more formal, we could say:
An illusion occurs when a person observes X and falsely or incorrectly perceives it to be Y, and X is not equal to Y.
In principle the "observation" can occur by any of the five senses, or even one of the "senses" outside of the big five. In practice most of the interesting examples involve either seeing or hearing.
I have used the words "falsely" and "incorrectly" in the above definition. We could try leaving them out, but the definition then becomes slightly problematic:
An illusion occurs when a person observes X and perceives it to be Y, and X is not equal to Y.
The problem with this definition is that there are many situations where a person can observe X, and, for example, see Y, and this seeing one thing as another is intentional.
For example, I look at a piece of paper with some black marks on it, and I "see" a dog, because actually I am looking at a drawing of a dog.
In most of these cases we can explain the perception of X as Y as relating to meaning, in particular, the meaning of X is Y.
Also, most of the time, the person doing the perceiving knows that their perception of X as Y has to do with meaning, and the perception of X as Y is not misleading in any way.
So when I look at the picture of a dog, I "see" the dog, but at the same time I know that it is not actually a dog. Also I understand that there is an intention that the drawing of the dog should be seen by the viewer as representing a dog.
Meaning implies the existence of a relationship between the thing that has the meaning and the meaning itself.
There are several different ways that things can have or be assigned meanings:
- Representational art in the form of pictures has meaning based on the visual similarities between the pictures and the things or situations represented by the pictures.
- A spoken language has meaning based on culturally defined assignment of meanings to all the words and syntax in the language.
- Other non-language-based forms of vocal communication have meaning which is defined mostly by instinct. For example, our understanding of the meaning of crying is instinctive – a person instinctively cries when they are very sad, and then other people instinctively know that if a person is crying it is because that person is sad.
In order to properly characterise what "illusion" means in terms of perceiving X as Y, we have to provide a definition that excludes all situations where the meaning of X is Y and therefore the perception of X as Y is not a "false" or "incorrect" perception.
The simplest way to define "illusion" in a manner that excludes situations involving meaning is just to make that the definition, that is:
An illusion occurs when a person observes X and perceives it to be Y, and this perception of X as Y is not due to X having a meaning which is Y.
In effect this definition declares that there are only two possibilities – if X is perceived as Y, then either it's meaningful, or it's an illusion.
Music: Meaning or Illusion?
Music is an example of X perceived as Y, where X is the sound of the music, and Y is the emotional feeling that we experience when listening to the music.
One can get into the tricky question as to what the "emotions" perceived when listening to music actually are, for example "sad" music feels sad, but it doesn't actually make us sad listening to it.
But, for the purpose of the current discussion, it is sufficient to note that some kind of emotional effect is perceived, and there is no obvious logical connection between that and the patterns of sounds that occur in the music.
So we can state that, in this case, whatever it is that Y actually is, it is definitely not equal to X.
We can also note that music only exists as a thing to be perceived. That is, it does not exist for any other reason. Music only exists because people make music, and people only make music in order to achieve the effects that occur when people listen to music.
So we have two basic features of music:
- Music only exists because of how it is perceived.
- When a person listens to music, hearing the sounds from which music is composed, that person also perceives an emotional effect, where the emotional effect has no obvious logical relationship to the patterns of sound in the music.
Putting those two things together, music is a thing X which causes the perception of another thing Y, and the only reason for music to exist is so that Y can be perceived.
And if we accept the dichotomy between meaning and illusion as stated in the previous section, then we are forced to ask a simple question:
Does music have meaning, or, is music an illusion?
And given the assumption that music only exists in order to be perceived, that question is more-or-less equivalent to this question:
Is music adaptive, or, is music not adaptive?
Putting those two questions together, we ask:
Is music meaningful and therefore adaptive, or, is music a non-adaptive illusion?
This is perhaps the most fundamental question that can be asked about music. I think it is fair to say that it has not been definitely and convincingly answered by anyone, although many people may have an opinion one way or the other.
Given the current state of knowledge about music, we might not be able to settle this question right now. But I think it is useful to consider various aspects of music and similarities of music to other phenomena, and how those considerations might point us to one or the other answer to this fundamental question.
Evidence and considerations arguing for adaptive meaning or for non-adaptive illusion
Music tends to become purely an entertainment
In modern Western societies, most people listen to music that they want to listen to, when they want to listen to it.
Music exists for entertainment reasons only – we listen to music because we like listening to music, and that is it.
The pleasure of listening to music is not connected to any apparent biological function.
In some less modern non-Western societies, music can be associated with particular ritualistic or ceremonial situations. This suggests that there might be more to music than just entertainment. On the other hand, it might suggest that the various "rituals" associated with music are themselves a form of entertainment, or at least they have music included so that they can be more entertaining to those taking part in them.
Music is not used pragmatically to communicate
If something has meaning, then in principle it can be used to communicate.
For example, if the meaning of music is the emotions that it provokes in the listener, then in principle music could be used to communicate emotion.
Yet, in practice, people do not use music to communicate emotion.
In particular, in normal conversation, no one ever starts singing, even if they are feeling emotional about something and wish to communicate that emotion to the other party (or parties) in the conversation.
Indeed, if you started singing in the middle of a conversation, those listening would assume that you are no longer conversing and that you started singing because you had the intention to give an entertaining performance.
If something exists purely as a form of entertainment, not obviously related to any other thing in the world, then that points to it being non-adaptive.
It is true that things which are meaningful can and are used as components in various forms of entertainment, for example:
- Spoken language is a major component of many forms of entertainment.
- An actor may cry (or pretend to cry) in a movie.
- Representational art is often created for the purpose of appreciation and enjoyment.
But, the important difference is that all these things can be used in normal conversation:
- Spoken language is the main component of normal conversation.
- A person may cry during a conversation, if they are very sad about something. Or crying may occur, and that then initiates a conversation because someone else nearby asks the person why they are crying.
- In a conversation, the person speaking might draw some pictures on a piece of paper to help explain something that they are talking about.
Whereas music cannot be used in normal conversation. (The only exception to this would be when the conversation is actually about music, but in such a situation the music is not being used to communicate, rather the music is the thing being communicated about.)
Mind-Altering Drugs
Various drugs can be regarded as causing perceptual illusions. This is slightly different from the X/Y situation, because the drug is not actually being perceived or observed – rather it is consumed (and it might have a particular taste or smell, but that's not particularly relevant), and then the effect of the drug on the brain and nervous system causes the person's perception of reality to be altered in various ways, giving rise to corresponding false perceptions such as (depending on the specific drug):
- Life is good
- All other people are very nice
- There is absolutely nothing to worry about
- The world is weird and interesting
- "We should totally do such-and-such ..."
But there are some similarities between music and recreational drugs:
- The drugs are created for the purpose of consuming them.
- People get pleasure from consuming the drugs, and this pleasure often has a discernible relationship to the false perceptions that the drugs create.
- People can get addicted to drugs.
Indeed there is one form of addictive behaviour that is related to music – so-called maladaptive daydreaming.
The maladaptive daydreamer is addicted to their daydreaming. But in many cases their ability to sustain their daydreaming activity is totally dependent on the music that they listen to while daydreaming. So in those cases, the person is effectively addicted to listening to music.
Skill and Precision
One distinctive feature of music is that people strongly prefer to listen to music that is performed to a high standard, and this requires the performers to be skillful and well practised.
Performer skill is required, because musical quality depends on precision of pitch and timing (and also precision of other aspects such as "voicing").
This requirement for skill and precision argues for music being illusory rather than meaningful, because, in general, the expression of meaning does not require unusual skill or precision, whereas the generation of illusory perceptions does usually require precision of expression.
Where meaning is involved, the execution is usually only required to be adequate, and the expression of the stimulus which has the meaning needs only to be accurate enough to state the required meaning.
For example:
- When speaking, unusual levels of skill are not required, pretty much everyone can speak, and even poorer quality speech is acceptable, as long as the listeners can work out what is being said.
- Everyone can cry – indeed it is an involuntary act (when not faked) that just happens, and certainly doesn't require a long history of practice.
- Representational art can be of a high quality, even photo-realistic, and it is impressive when done skillfully. But at the same time, the complexity of representation in a drawing or diagram can be the absolute minimum required for viewers to determine what is being represented, and that absolute minimum is considered quite satisfactory in most cases.
Illusions, on the other hand, often require quite precise execution. Many visual illusions consist of geometric patterns that are both repetitive and very precise, to the extent that they have to be computer generated rather than hand drawn.
For example, it would be quite difficult to draw a functioning version of this illusion by hand.
But, music feels like it's communicating something!
So far I have given reasons to suppose that music is probably an illusion, and is not functionally or adaptively meaningful.
And yet, when we listen to music, and especially when we watch someone perform music in front of an audience, there is a strong feeling that the performer is communicating something with powerful emotion.
This could of course just be part of the illusion.
It is paradoxical that music can create this feeling that communication is happening, and yet at the same time our brains strongly reject the use of music or song in normal conversation.
It's as if one part of the brain succumbs to the illusion, but some other part of the brain knows that it's just an illusion, and in effect says - "I know this feels powerful, but don't actually take it seriously."
There are elements of "melody" and "rhythm" in normal spoken language.
However melody and rhythm by themselves cannot be used to construct any type of spoken language that communicates in a setting where communication is expected.
But perhaps there existed some other kind of language, used by our prehistoric ancestors in the distant past, before spoken language as we know it existed, and this prehistoric language did use melody and rhythm of some kind to express emotional meaning.
There may have existed some kind of pre-musical protomusic, which consisted of a language based on melody and rhythm, and which expressed emotion of some kind, and music as we know it is somehow descended from that original protomusical language of emotion.
Even if this is the case, music may still be an illusion, but, it is based on some lingering trace of a past prehistoric adapative and meaningful language of emotion.
A protomusical language of emotion would have had ways of expressing specific types of emotion such as happiness and sadness. It may be that features derived from the meaningful protomusical ancestor are what determine the specific qualities of emotion that music expresses, but it is the illusory aspects of music that determine the intensity of the emotion experienced by the listeners.
Protomusic, in its pre-illusory stage, would not have had the aspects that I have previously identified as evidence in favour of the illusory nature of music, that is:
- Protomusic would have been used to communicate pragmatically, in situations that we would regard as "conversation" (although such prehistorical emotional conversation might have had a different structure and flow to what modern spoken language has).
- Protomusic would not have required precision or exceptional performer skill in the way that music requires.
- Protomusic would not have had any addictive qualities, and would not itself have been a form of entertainment.
If music is indeed such a combination of illusion and meaning (or at least pre-historical meaning), that may be why it's so hard for us to decide which of those two things it actually is.