Perhaps there is an easy answer to this, but I couldn't find it. How can information be defined? It exists, but it can be multiplied indefinitely without losing anything. So that excludes it as a type of energy, since it can be created. So what is it?

  • sounds maybe like it is this fallacy en.wikipedia.org/wiki/Fallacy_of_composition. unless you are just using an analogy to raise the question of what is knowledge
    – user25714
    Jun 14, 2017 at 20:53
  • See Physicalism for the philosophical issues related to the thesis that everything is physical. Maybe was Berkley right ? "everything is mental". Jun 15, 2017 at 9:15
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    some forms of physicalism argue that everything supervenes on the physical (which is pointed out in the article Mauro linked to). Knowledge could be something abstract, but it supervenes on brain functions, biology, chemistry, physics...
    – Not_Here
    Jun 15, 2017 at 12:43
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    What is 'on top of', 'two', or 'in a line'? All of those exist, but none are matter or energy. They are relationships between things that do exist. Structures. Jun 15, 2017 at 15:43
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    knowledge != information. which question are you asking?
    – user20153
    Jun 15, 2017 at 19:58

6 Answers 6


(The framing seems to assume some form of physicalism, so I am going to answer in terms of modern physics. There are good philosophical reasons to question physicalism. But I do not think this is part of the question.)

The closest concept that enters physics is information = negative entropy, the ability to direct energy so that it does not disrupt an expected state.

Physics does include entropy, which measures the orderliness of a system, as a real thing, especially in thermodynamics.

According to thermodynamic principles, the overall entropy of a system must increase over time, but positive entropy can be traded for negative entropy. This means that we (and other forms of life) must expend energy in some way that causes waste, in order to retain the predictable patterns on which knowledge relies, and over which it gives us influence.

So your observation that it can be multiplied without loss is not true. Some energy must necessarily be expended and turned into an unusable form, or no more information can be created. Those people remembering it have to eat, the paper that book is printed on had to grow and will rot, those bits stored in a computer require current flow in a circuit, that recorded medium will degrade over time and will have to be copied before it is unreadable, etc.

  • I like your response and how you tie it to the physical medium that information is reproduced on. But I still fell that the OP is on to something: A recording of a Bach piece maybe be subject to the laws of thermodynamics, as well as the original ink patterns and paper he wrote the score on, but the score itself can be reproduced ad-infinitum without any loss. There is something about pure information that seems to defy thermodynamics. Jun 15, 2017 at 23:51
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    @AlexanderSKing I didn't say the lack of degradation was impossible, only that the lack of degradation just requires more energy. Negative entropy requires offsetting positive entropy. Even digital media decay unless they are re-impressed regularly. The contention was 'without losing anything'. The knowledge itself is never lost, but there is loss, in the form of wasted energy, in order to maintain it. If you assiduously maintain a building, it could never decay -- that does not mean it escaped entropy.
    – user9166
    Jun 16, 2017 at 0:07
  • Hmmm, I beg to differ: The physical medium maybe lossy, but not the information itself. A building maybe maintained, but it will never be the same building it was when it was first built, imperfections and differences are inevitable. A perfect replica of building or a painting is impossible, but a perfect replica of a text or a mathematical formula is. It's almost like reverse DesCartes: It's not that matter is divisible while matter isn't, it's that ideas can be multiplied while matter can't. Jun 19, 2017 at 1:32
  • @AlexanderSKing Entropy is not matter, the pattern does not involve every detail. You are claiming that the flaws in the matter necessarily affect the degree to which the object controls energy. In some sense, all that can ever be maintained is the 'information' of the building -- the shape is not the object, it is an aspect of meaning that the building has, independent of its physical contents.
    – user9166
    Jun 19, 2017 at 15:11
  • And a 'perfect' replica, one that serves all the same purposes (or maintains the same homeostasis in other terms, when we are not discussing humans) is just as possible as a perfect replica of a formula. The cracks in the wall do not contain meaning, the exact shape of the integral sign is just that kind of detail, and is not maintained. But it will in the process always require energy. The argument her is that information is a form of negative entropy, not material content or energy flow.
    – user9166
    Jun 19, 2017 at 15:13

Then looking at knowledge one must look at the concept of knowledge: One Greek filosofer states that he knows nothing but this he knows:

"I know that I know nothing" - Socrates.

In other words: he realizes that every thing he bases his knowledge on is based on the knowledge of others. Just because one understands the line of thought dose not mean that it is true. "Why do I have two hands?" "Sow you can hold the bible you read" is a classic eksample because the question is answered with God.

An other thought is:

"I think, therefore I am" - Descartes

In this understanding knowledge is simple a product of thinking because the pure knowledge som from this. Knowledge is not defined but relative to you. This is why "God" is needed, he defines your "ground state".

Today information can be stored, meaning that a certain arrangement of electrons can lead to the storage of knowledge. To sum up: knowledge is matter of definition.


Knowledge is a label for the electrical/chemical status of particular elements of the brain. That brain state is the physical manifestation, but -since we don't typically observe any of that directly- humans generally identify with the experience of 'knowing' something instead of the physics of it.

Compare to 'happiness,' which is a similar label for what happens to the body under the influence of particular hormones. Or anger. Or a decision.

The physical manifestation of these things are arcane, and do not lend themselves to easy understanding in context of day-to-day life. People had created these labels (and spent thousands of years philosphizing and debating over them) before we had any notion of the neuro-chemistry from which they spring.

  • Physicalism as hinted by jobermark in his answer above is a questionable assumption. The very observation that we can think of these concepts (or labels as you call them) without even being aware of those corresponding chemical interactions on the bodily level, and moreover how concepts of mind don't seem to possess any properties of matter in our intuition, and finally how the very perception of this duality could be even possible under Physicalism, poses serious challenges to the theory.
    – infatuated
    Jun 16, 2017 at 13:29
  • I get the idea of thoughts existing in some other dimension, apart from our observable universe. I just don't see much evidence for that as an accurate, useful model of reality. When there is a reasonably supported, natural explanation for how thought/knowledge works, I see no reason to accept more complex, less well supported supernatural models as viable (i.e. Occam's Razor). When that more complex, supernatural model is unable to generate testable/observable predictions, then it is about as useful as models of the mind based upon butterfly wings & pixie dust. Jun 16, 2017 at 14:53

Just like software, knowledge has no real physical manifestation. What the software is stored on is physical, but software itself is more like automated concepts.

The same could be said of music: it can be written down and played, but the value of it, the reason we listen to it, exists only in our minds.

Or... you are physical, your car is physical, but what is the route you take to get to your destination? Yes, the road is physical, but your knowledge of where to go and how to get there has no real presence. More motivation or desire.

Think of knowledge as software for the human brain. It can extend your brain, increase your capacity to understand or take action. You can run it, pass it on (though the data transfer rate is slow, and there is no automatic error checking), or even delete it.

But, it has no physical manifestation. No Brain App Store, either. Wouldn't that be nice? You could buy your information, instead of having to accumulate it manually. Beware the prejudice, jealousy, hatred, and greed apps, though... they're a free download, but you pay a huge price every time you use them.


I can supply a perspective from my own (Iranian-Islamic) philosophical heritage.

Iranian Sadraian philosophers such as Allama Tabataba'i define knowledge in the broadest term as simply "the presence of a thing for another thing" where the two things are both immaterial in nature with the first thing being the knower (or "the subject" to use a fairly equivalent Western term) and the second thing being "the known" (or "the object").

This definition presumes a unity between the two since mind is believed to unite with the form of the known object once it gains knowledge thereabout, with the acquired form corresponding to the transcendental active cause of the perceived object, residing on a higher plane of existence (paralleling the Platonic theory of "Ideas").

So according to this view, every form of knowledge transcends the material world. Tabataba'i supplies a few arguments for supporting immaterial nature of knowledge. I describe only two of them that I deem to be stronger.

  1. Humans can invoke and recall mental concepts and images from distant past which would be impossible if they were somehow "stored" in human brain or any other physical organ, as the constantly changing feature of natural things undermines any ability to preserve mental concepts through time.

  2. The simple nature of abstract concepts negates the possibility of material basis for their preservation as a simple entity can't be ingrained in/on a composite entity.

As for transcendental origin of knowledge, after establishing its immaterial nature, he argues from the fact that neither human mind by itself nor the external world of matter can be a source for something that neither originally existed in the mind nor can come from things that are of a completely different nature, i.e. physical entities, hence the necessary existence of a higher source that embodies all forms of knowledge and is immaterial too.


Knowledge is storage of experienced examples; it is analogue to (free) energy.

Matter° (chemical substance) is simultaneously the medium to enable (e.g. physical) processes and to store the energy of these processes*. This stored energy is called the free energy A (Helmholtz energy).

Our life is analogous to the just mentioned matter°, it is the medium to enable physical and mental experiences (this is the analogue of the above processes*) and to store the results. These stored experiences are called knowledge (this is the analogue of free energy).

How these experiences are collected, how different kinds of them cooperate in this process, how they are stored, and how they are classified as examples, as inductions, as deductions, as analogies and as abductions, is described here.

All this cooperation, storage and classification of experiences occurs in our brain, in books, journals and electronic databases. — When reflecting about this, one sees that knowledge consists of stored experienced examples.

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