We cannot know what the world is - only what it is like.
This could sound like a trivial distinction. The statement has a ring of the well known about it. Our impulse is to say “Well yes, obviously.” as though there could be nothing new there. But despite seeming obvious it is not well understood, and when the implications are properly explored they are world changing.
But the first question might be “How true is it?” That would be a good question and the answer leads again into the nature of truth. My assertion is that it is true beyond biology – not just a human condition, beyond epistemology – not just a property of knowing, but true to the point of metaphysics. It is a fundamental property of any conceivable universe. Indeed it might even be the fundamental property of the universe. I am aware that that claim might seem far fetched at this stage, after all, how can some statement about knowing (for which at least some kind of mind must be invoked) be more fundamental than some basic physical property such as gravity, or metaphysical property such as propensity. Hopefully we can get to a point Jessie, where the idea seems as clear to you as it does to me, and no, it will not involve any mystical magic. For now though, let us stick to something simpler. Why is the opening statement true to the point of metaphysics?
No complex system can include a representation of another system that is complete in every detail. This is because no two things are the same thing. Korzybski had this covered. No one thing is another. It may seem as though in the digital age we can form perfect representations. Suppose we have two computers. The first runs the simplest of programs. Perhaps and infinite loop that does nothing. Could we not say that a second computer which runs the same program 'knows' or represents the original program perfectly. Yet the first program is not the second. One thing is not another. We can pull the plug on the first computer and yet the second computer, running the same program is unaffected. Rather than representing the 'other' perfectly it is now awry. The second computer did not 'know the world' it knew only what the world was like – and it was very like the one in which its program ran. Until it wasn't.
That we cannot know the world has been covered before in various schools of thought. Alfred Korzybski in Science and Sanity wrote extensively on the idea that the world was what it was: it existed in the unspeakable realm, and that our representations of it were not the thing itself. Similarly the phenomenologist school refers to the world as ultimately 'unknowable'.
So it may be fundamental that we cannot know the world, but it is also fundamental that we can know what the world is like. That is, we can build models of it that have 'alikeness' to it. Models that give us reliable predictions. So the world is like one in which objects have a mutual attraction: gravity. It is like one in which electrons surround atoms, and in which mother-in-laws behave in certain ways, and political parties are good, bad or indifferent. In fact all human enquiry takes the form of 'what is the world like?' Up until now we have largely put our emphasis on the word 'is': “What is the world...” and barely at all on the word 'like': “What is the world like?”
At this point a number of questions arise which lead off in different directions. One way we can ask “How is it that we can make models that are like the world?” “Why is that even possible?” This way takes us back to metaphysics (and as we will see, calls in on the second law of thermodynamics). In another direction we can ask: “What is the nature of what we can know?” If all that can be known is what the world is like then a lot rides on the nature of alikeness. What does it even mean for one thing to be like another? What is the shape and measure of alikeness? This way leads on, but calls in on Occam's razor and the second law of thermodynamics. Once these two avenues are explored we find some solid ground for going forward. For asking the question “So what?” “What does it mean or matter?” And this, I think, is where the juice is.
The way in which we understand the world is deeply metaphorical. This is well understood by anyone coming from a symbolic modelling/Clean Language background. These are people who have spent time working therapeutically with client's problems. Or more specifically with metaphors that arise to describe the complexity of a personal situation or problem.
All of our understanding of the world comes from metaphor. Knowing what the world is like. We often learn about metaphor as a literary trick – a way to add poetry where cold hard facts will not do (as though a fact could be cold or hard). It can easily escape our attention that metaphor in the broadest sense (talking about one thing in terms of another) so permeates our language that we can hardly write a sentence without it. Facts are cold and hard, senses are broad, avenues are explored and ground is solid. This ubiquity of metaphor is the first clue to the fundamental nature of metaphor in thought. It is in fact more than just common, it is 'the stuff of thought'. Our mental models are hierarchical constructions of relationships, one thing to another, grounded in our basic physical experiences, the way gravity differentiates up from down, our experience of light and dark and so on. Minds are made of likeness processing.
It is easy to see that if someone says they are feeling bound, they are using a metaphor, after all there are no physical bonds to bind them. And that the same holds when the 'bound' metaphor enters the language more subtly - “He's bound to complain about that.” This sentence invokes the 'bound' metaphor. It also reveals the model of the speaker who has observed the world and its operation in relation to 'him' or people like 'him', 'that' or situations like 'that' and outcomes such as complaining.
The speaker has constructed a model, which they are able to use to make predictions about outcomes in a given situation. In this case within the action of the model 'he' has become bound or tied in some way to the outcome of complaining. There is more to be said about the relationship between such models and metaphors but for now we can safely view the whole model a metaphor. We can see that this model may be a good and accurate one or may be fallacious. In other words it may be a good or a poor 'fit'.
But what about our more scientific ideas? Electricity, gravity and so on. Most scientists are familiar with the history of science and know the story of the atomic model. The Greeks first hypothesised the world to be made of tiny particles to small to be seen, that were made of the essential nature of stuff. That all matter was composed of tiny particles like the grains of sand on a beach. They called these hypothesised particles 'atoms' to mean indivisible (a-tomos – no cutting). The alchemists of the middle ages refined their understanding of what types of atoms existed, they called these the elements. The enlightenment chemists derived the rules for interactions between elements to make up 'compounds' meaning materials compounded of elements. Compounds were understood to be made when atoms of various elements bonded to each other. These bonded atoms were called molecules (from mole - latin massive and -clue french diminutive) an initially vague word first used by Descartes which gained its modern meaning with Avogadro. The next step was a big one, to understand the mechanism by which atoms could bind their indivisible nature had to be challenged and the notion of an atom composed of some number of electrons arose (electrons were first known as 'atoms of electricity' or 'corpuscles'). Electrons could explain the formation of compounds in chemistry. The initial idea was of electrons embedded in the atom like 'fruit in a plum pudding' until Bohr described atoms as having a small nucleus with electrons orbiting like planets. From there with the development of quantum physics came the description of electron orbits as a cloud of probability rather than a path along which an electron would travel. This is fairly standard, if brief account. It is also a story. A story, as it is usually told, of the slow uncovering of truth. Of the ever more subtle and refined understanding of the world, giving rise to ever greater technology and progress. While this story of 'ever closer to the truth' is perhaps accurate, we gain insight when we shift the emphasis from the 'truth' to the 'closer'. The development of science is one of ever better and more reliable metaphors.