The aim of this page is to attempt to explain and describe what is felt by agents. What we are describing may be called 'subjective experience,' or sensation, emotion and thought taken together. We don't use the word perception because that can refer to latent attitudes: 'Stop watching TV because it distorts your perception of what is important.'

On description


It’s impossible to know whether experience is finite. For example, how many different temperatures can be felt? In introspection, one has beliefs come into his mind about what he is feeling, and he may identify a scale of feelings. In any description of his perception that he may come out with, it will always be finite. He can easily express the possibility of an infinity of different grades of feeling, but when trying to relate his current feelings to what he has felt at other times, he will only have a finite number of concepts that he can identify them with. (It's also worth noting that the eyes move in bursts, and only see when they is still. There isn't a huge number of intermediate images that are used to make up experience.)

Peripheral consciousness and memory

It's also hard to know whether you were feeling things that you weren't thinking about a second ago. If I think about my foot touching the floor, I know that I am feeling it, but I don't have a memory of feeling my foot touching the floor a second ago when I wasn't thinking about it, and I can't tell whether it was part of my consciousness or not.

Emotion and sensation

It is hard to separate the various aspects of experience from each other. Emotion' does not seem to include experiences like that viewing an image, or sensations of touch, which could be accompanied by a range of emotional reactions. We call the class of aspects of experience that are unemotional sensation, which we contrast with emotion. What the difference between the two is a question worth considering. Any postulated class of aspects of experience is not found on its own, such as a thread of pure emotionless, or pure emotional, perception. All classes occur together as part of the whole perception.

It is worth asking whether emotion is just a special case of sensation, or whether they are the same thing as each other. I tend to think that they are different. It can be difficult to separate the two. The sensation of hunger can lead to the emotion of fear or of unhappiness. The sensation of the thought that one will soon have food can lead to happiness.

The division of experience into emotional and non-emotional is problematic, though. There are some aspects that seem to be both. Ending hunger by eating is both emotionally satisfying and a physical feeling, in the mouth and stomach. I am not sure if eating without pleasure feels physically different. The feeling of stretching aching muscles is physical but can pleasurable and satisfying too. There are also feelings such as thirst, headaches, and the comfortable feeling of sitting in a soft chair, especially if one is sitting down after a long time standing up and it is a relief.

We might view the class of emotion as a consequence of the class of sensation, and try to work out what the relationship is.

I want to find unities in varying experiences. Do, for example, the feeling of rapid breathing in cold air into the lungs when one is out of breath and is trying to recover, the feeling of drinking cold water to quench thirst, and the feeling of stretching tired and aching muscles have something in common, perhaps the feeling of blood flowing to the area of body in question?

We are looking for unities in both directions. We'd like to be able to identify the emotions in experiences with different sensations, and to identify the sensations in experiences with different emotions, as in the following diagram:

\ Emotional state ->
Sensational state
  Experience *----------------* Experience
             |    <----->
             |     seek unities
             | ^
             | |
             | | seek unities
             | |
             | V
  Experience *


I imagine the description of experience to be like this:

  • A number of actors each with their own thread of experience
  • Each thread of experience is divided into channels, one for each class of sensory experience
    • There are a fixed number of elements of experience. Each has an extent in time, but two threads are isomorphic if their elements overlap in the same way. This is because perception of the passage of time is itself part of experience. There are several ways of expressing this mathematically. We are viewing threads and channels as data structures, but at the bottom level instead of integers or sets, we have elements like 'blue colour' or 'raspberry taste.'
    • Each element has an additional attribute indicating whether it is part of direct or indirect consciousness. For the reason above, someone trying to write down their experience in the system that we shall specify will have a harder time describing the direct than the indirect parts.
  • We have to remember that the channels are not isolated, but work together to describe the same thing. For example, you can touch something and look at it at the same time. This was noted by Aristotle.

I hope some of this will lead to formal reasoning, the 'emotional calculus' that was envisioned in the title of this site when I created it over a year ago. Call the postulated data structure containing all the information about subjective experience and physical reality and the relations between them $\omega$. Call the set of all possible data structures $\Omega$. Statements of fact are predicates $T(\omega)$, and likewise imperative statements (commands, deontic propositions, whatever) are predicates $P(\omega)$ (where $T$ and $P$ are named after 'theory' and 'practice.').1 We have assumed $T$ and $P$ to be Boolean, but in line with the principle that we only know reality through the brain's perception of it, and the brain works by a process of matching perceived forms to pre-stored patterns, $T$ and $P$ could in fact have a more refined codomain, each element therein corresponding to a particular level of certainty in pattern matching. (This is 'fuzzy logic.') All these details are yet to be worked out (by me). I hope for a formal mathematical, logical, philosophical language. (Here I will note that this was something aspired to in early modern times, such as Leibniz's idea of a calculus rationator - in case any of these ideas shall be useful.) Sentences within the language are 'fragments' of a description of $\Omega$. In principle $T$ could be anything - a completely arbitrary subset of $\Omega$ could map to $True$. However the way that we describe $T$ should make it easy to describe 'concepts,' which are not completely arbitrary.
* There are two definitions of concept. One is roughly speaking something you have given a name to, or could do so easily. The other is a pattern we have learned to recognize, and is associated with emotional reactions and possibilities for actions. A concept in the latter we imagine to be quite a fundamental part of how the human being operates.

Natural language is flawed because each sentence expresses only a fragment of the whole subject to be explained. Just think of the sheer inanity of popular political debate, which completely fails to explore essential avenues of inquiry (broken window fallacy). In a formal language the simple pattern of '[agent] [action] [patient]' occurring in temporally sequenced clauses (i.e. in prose, the sentences are in a particular order) could be replaced with a single structure, which wouldn't necessarily have to map uniquely onto a conventional representation, which expresses states of affairs, intention, causation and everything else.

  • There's a difference between 'X' and 'I think that X is true.'

Whatever the nature of perception is, it occurs in individual threads of subjective experience. Ideally we would like to enumerate all the identifiable aspects of perception, so that we could completely describe what the life thread is, as a sequence of overlapping tenures of aspects, each a certain length of time. Until this project is completed, one can always have things to think about, because he always has his own perception.

One tends to think of a person's conscious subjective experience as a continuous function from a length of time T to some set S of possible frames of consciousness. Time is viewed as a totally ordered set (a < b means time a is before time b), dense in that for all a < b, there exists a < c < b. We could ask questions like: What is T? Is it some interval in the rationals, or reals? If not, what is the cardinality of T? What do we mean by continuous? Is this a continuous map of metric spaces or topological spaces? What is S and what is an open set in S?

It's possible to bypass all these questions by viewing your experience as a finite object. If you think about your experience and your memories of the experience you can only think of finitely things you experienced. If we identified a fixed point in T, there would be a certain number of subjective principles that extended to an interval about that point. What are these principles? Principles describing any part of subjective experience. Seeing a hair on the back of a small dog in the corner of your vision. Having a warm left foot. Imagining lengths of space and time. Perceptions of slight differences, such as in temperature. Shed the embedding these principles as intervals in the reals and only keep the structure of how they overlapped with each other. This is the finite object. The identification of time with the reals is appealing because physics seems to obey rules that use a concept of real time, and our subjective experiences are consistent with these physical laws.

Aspects of perception

Here are some subjective phenomena upon which to ponder:

  • Feeling awake
  • Being very sleepy - When going to sleep, I have a feeling of being interested in the content of my own head, even though I have few conscious thoughts. It may be the opposite feeling to the comedown after having drunk lots of coffee, when everything is tiresome.
  • Being too exhausted to sleep, or being too cold to sleep
  • Late night hyperactivity - thinking about all the great things one will do tomorrow morning, as long as one can get to sleep tonight, which of course he can't
  • Knowledge and power - Both attributes which we are glad to get as much of as is possible.
  • Morning sunlight - Not just light, but an actual feeling of goodness and beauty. Good if you've gotten up and are gearing up for a day of activity (chopping firewood, hanging out with your schoolbuddies down the municipal dump, or whatever else you do with your time). Bad if you are still trying to sleep.
    • I think that maybe the only basic emotion is pain, and the lack of it which is pleasure. These may be two different feelings but they are so linked together closely. Pain is when your different parts (e.g. the bit of you making you awake and the bit of you which is exhausted) are working disharmoniously, and pleasure the opposite.
  • Fresh air
  • Cleanness - A sense of preparedness and purpose, when one confident that
  • Enthusiasm - An urging to do things and to get your hands on something, or when you are looking forward to something
  • Dread - The fear of being trapped, or doing something over and over again. You might get this emotion watching documentaries about the Holocaust.
  • Contentment - What is felt when one hears the tonic note in a musical scale, or when one hears the click in the doorframe after successfully closing a door; the feeling of success, in prediction or action
  • Fear - Comes from uncertainty. Feels like being cold.
  • Irritation - Much the same as fear.
  • Horror - If you think you going to be attacked by a wild animal (or uncontrolled domestic pet), your pupils may dilate and your hair will stick on end (this happens to monkeys too) and you will be ready to take decisive action
  • Sadness - Can come from a sense of loss or wishing that things were different and having no way to change them. Notably, you can be depressed but calm. Depression might be something else though.
  • Satisfaction - Succeeding in increasing one's comfort as a result of some effort could lead to satisfaction.
  • Sense of achievement - This can apply even if comfort is not immediately improved. Someone scoring a penalty in football, or opening a box with a low amount of money on Deal or No Deal, or getting a question right in a quiz, doesn't immediately have physical feelings change. Imagine the 1p box on Deal or No Deal contained a slice of cake, and a hungry contestant opened it and ate the cake. He would be satisfied in two different ways. This might be related to self-worth. If someone told himself that he was psychic and that's why he guessed the location of the 1p box then he would have a smug sense of self-worth, which everyone might not have. This sense of self-worth would not occur on occasions when good things happened to someone that they could not possibly claim the credit for - such as unexpectedly finding money in an old coat pocket. There is self-worth from achievement, and self-worth from being loved. If someone gets given a Christmas present, and satisfaction is gained, the satisfaction is not one of achievement, but a combination of the sense of being appreciated and the enjoyment that one would get from the present per se, which would still have been there if someone had gone into a shop and bought it himself.
  • Enthusiasm for a mode of living - such as nostalgia
  • Frustration - feeling like you've wasted a lot of time and are getting nowhere, especially when what you're doing isn't too hard
  • Ennui - Feeling like you should do something, but not knowing what
  • Rage - Mostly a physical feeling, with actions like shaking a fist and being red in the face, combined with a desire to be active
  • Ecstasy - I don't know if others have used this word the way I am using it, but an emotion that can comes from listening to moving music, or contemplating great actions that one does in his life, in relation to the proportion of his lifespan that it will have an effect on.
  • Pain, Discomfort - a lot of pain is accompanied by a desire for its removal - in fact, it may not even be pain if that desire is not present. In some cases, the desire is accompanied by a habit ready to be put into action. If some suddenly needs a piss, the habit of walking to where the toilet is will pop into their head. If someone is suddenly hungry, or thirsty, then something similar might happen. In other cases, though, there is no such habit. Stubbing one's toe for example. When someone stubs their toe, there's nothing they can do. In other cases it may differ depending on the circumstances. If someone is tired of standing up, or if they are hanging waiting to be picked up by someone with a car, then they are uncomfortable, but there's nothing they can do. If a chair appears though, or if the car arrives, then the relevant habit will come to mind - to sit down, or get in the car.
  • Annoyance at messiness - if one avenue of action leads into something which is disorganized - such as disorganized lecture notes, or the whole messy world of job-hunting, then someone might be dissuaded from going down that avenue. (Ethical recommendation: keep things tidy, to minimize this dynamic.)
  • Trying to remember something - but only having peripheral thoughts come to mind. These thoughts flash in the mind briefly, making you sure that there is something behind them, but it is if there is a wall between it and your conscious mind.
  • Satisfying or unsatisfying feeling in the digestive system - in at least the bowels and stomach.
  • Pleasure at having clean teeth
  • Being 'driven' - One effect of meth. Not from personal experience! But I have had similar but milder symptoms from caffeine. I think an excess of drive can be a cause of compulsive behaviour. Drive explains why we fidget, doing things like fiddling with pens. There is energy there and it has to go into doing something. It could go into physical or mental activity.
  • Having the potential to do stuff given willpower - this a graduated quality - when you are exhausted or hungry, it takes a lot of willpower to do something. When you have had a good night's sleep, a good breakfast, and it is sunny, it is not so hard.
  • Resting attention on a vivid mental image - I feel like I am writing in my brain, re-inking a faint outline.
  • Satisfaction at having reached a new level of understanding
  • Discomfort owing to elements within peripheral consciousness. Someone has a dirty street outside their house. When they are inside, they don't think about it all the time, but a lot of the time they may feel very slightly uncomfortable about the fact that selfish morons are dropping litter, without actively thinking about it.
  • Boredom - knowing when boredom and interest occur could tell us a lot about the internal representation of knowledge
  • Fog - I find fog poignant and energizing. Photographs of fog, or damp conditions have a similar effect, but one no greater than any such example of reflected direct experience can have.
  • Frustration - This occurs whenever things aren't progressing as quickly as they should be, such as when one is stuck in traffic.
    • Suppose someone is walking somewhere. They haven't walked along this route before and it is taking longer than they thought it would. If they does the same every day, he will get used to it and won't feel that way any more. However, it is still tiring for their legs, and they still experience physical pain.

See Wikipedia on Senses.

We could look at the implications for behaviour and learning for all of these.


Thought is a special case of sensation. Just as we can say that one hand is warmer than the other, we can also say that we see in our mind two and three coming together to make five, and both are perceptions with no specific emotions necessarily attached. Thought involves processes such as abstraction.

Some thoughts are verbal expressions (or fragments thereof). They, like other mental phenomena, come from the subconscious, and how the subconscious works is hard to know.

A division may be made according to the different circumstances that the experience that an emotion occurs in or refers to, namely whether the experience is, perhaps among other categories, past, present, future or hypothetical; so enthusiasm, say, may be viewed as future doing, or so nostalgia, perhaps expressed or invoked by mournful music, is past living.


Sensation includes aspects such as feeling and seeing. It is used to make a model of our physical environment, including aspects such as the direction of gravity and the speeds of physical objects. There are internal senses like hunger, balance, sense of the passage of time and what part of the day it is.

There are several flaws that can easily occur models of the physical world that are inferred from sensations. Here are some of them:

  • We think that there is a downward direction in which objects fall, but if we extend this direction throughout three-dimensional space then on the other side of the globe of the Earth, we would see objects falling upward. Our intuitive notion tells us that the world is flat, but we need to adjust this notion, for example when sailing a ship around the world, or working out how to put a communications satellite in orbit.
  • We think that there is such a thing as being stationary. But according to the principle of Galilean relativity, there's no special inertial frame of reference - we can only say if something is accelerating or not, not whether it is moving.
  • We think that there is such a thing as three-dimensional space, which extends infinitely in all directions, and which may be zoomed in on infinitely. Euclidean geometry works in this space. But according to general relativity, it's better to think of it as a Riemannian manifold. If we consider quantum mechanics, we might have problems with the idea of zooming in to infinitely small views.
  • We think that there is such a thing as linear, absolute time. But general relativity showed that different observers can have their own times.
  • We see objects as being made of continuous, homogeneous materials, as opposed to being made up of particles. Solids, liquids, flames, air and smoke are all viewed in their own way.

In search of general principles

It's possible that pain is merely disharmony between the urges and pleasure is harmony, or that some other simple principle is the case. However, this is highly abstract, and human experience will always consist of specific examples of phenomenal classes. Even if we do get an explaining principle, this is of questionable utility on its own, and we wish to continue describing the specific types of classes and when they occur, in their full manifestation.

It seems that the urges relating to pain and pleasure occur in classes of situation where following such urges in one of these situations made one's ancestors more likely to survive and reproduce. However, this is not an infallible guide. Sometimes you might get food poisoning or syphilis. (See also: 'Lies', below.) (This may be an argument against solipsism. The way you feel now depends on what your ancestors did.) And it's not necessarily true that all aspects of experience can be described this way. How much did our hominid ancestors shoot heroin? The emotional correlate of brain chemistry is explained by evolution, but the fact that this is an emotional correlate of this specific method of changing it isn't.

Emotions are behavioural as well as being subjective phenomena. They have implications for memory and learning.

There may be a parallel between learning in one individual, and evolution. Suppose someone is in the habit of not eating breakfast. They feel absolutely foul each morning. One day they eat breakfast and they suddenly feel a lot better. They realize that the reason that they felt so bad was that they were hungry, and resolve to eat breakfast from now on. In the future, they don't feel as bad when they get up, at the time before they have eaten, because they've learned to expect nutrition. By this application of willpower, and forcing themselves to eat breakfast, they change how they feel at this time. Species also learn, over time with biological evolution, and perhaps further attention will produce a more detailed analogy. For example, the productive part of reproduction is the moment of the act of giving birth. This does not mean that the only meaning of life is to reproduce, because the appeal of this short moment spreads backwards throughout what leads up to it.

The reason I think there may be such an analogy is because I'm struck by what I explained three paragraphs above. I'd been considering a cosmogenic account where an emotion was a property of an organism acting within an environment. Each emotion would have a certain implications for behaviour and learning in the organism. The universe was created subject to this constraint, by a kind of 'anthropic principle.' (This explains why feelings like pain exist. It is impossible for one's experience of the world to be exactly the same, except that pain is removed, because pain is a property of the organism. (Notably it tries to get out of pain and stop the situations where it occurred happening again.)) (This agrees with the idea of Purusha in Hinduism as a 'universal man.' He is not an individual man, but the Platonic form of a man.)

A rich person and a poor person have different levels of comfort, but might have similar emotions. High comfort is preferable. On the other hand, emotions are aligned to the current situation, relative to the circumstances and temporal changes thereof. The same emotion could be invoked by different changes in the level of comfort.

Sometimes, late in the evening, I feel tired and depressed. When I realize that I always feel like this, I may feel less depressed, even though I have the same level of energy and interest. If one is cold, he may dread being cold forever. However, if he is going through a cold town going to meet some friends, or if he is aware that once he gets home he can get warmed up, then he can have a much more optimistic view of the situation.

I think that some old people can look very content, and confident and certain in all circumstances. This may be because they have acquired a strong knowledge about how they will feel in different circumstances, which is a consequence of the feedback loop in their minds telling them what they are feeling. Even though they perhaps couldn't articulate their understanding, and it is not a result of any deliberate course of introspective study, they maybe couldn't help but acquire such an understanding, having lived a long and stable life where they repeatedly feel the same way at similar times in the day having done similar activities.

We know that we have emotions, and they can be described scientifically, in terms of biology. It would be cool if one could learn how to work out quantitatively how much there is of various neurotransmitters sloshing around inside one's brain, or what one's blood glucose level is, by introspection alone. This may already be possible, but if it isn't, I think science will get there.

We need to consider what the correct applications of the relativistic doctrine are, which is the idea that everyone is equally happy regardless of their circumstances, such as whether they are rich or poor.

We need to work out what the differences are between different cases where events turn out better than expected. Sometimes an unexpected boon can make one happy, at other times relieved, but at further times shaking at the possibility of what might have happened. If someone nearly drowns and is rescued, the rescue is a good thing, but the person may not feel as if a good thing has happened.

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