What is knowledge theory?

What is truth, and what is knowledge? Philosophers have been discussing these questions for thousands of years. Knowledge theory is also called epistemology. It is about the nature of knowledge. It deals with truth, belief, and the justification of beliefs. It aims to answer questions such as: What do we know? What does it mean that we know something? And what makes beliefs justified? We usually acquire knowledge in two ways:

• by induction, which is using observations to formulate general rules or theories and
• by deduction, which is applying those rules and theories to specific situations.

For instance, after carefully observing the available records of all the people who have lived and still live, you arrive with the help of induction at a general rule that people die before they turn 120. Then, using this rule and deduction, you infer that you will die before the age of 120. That seems straightforward, but there are pitfalls. That is why philosophers are still discussing these issues.

There is a difference between rules and theories. A rule is that if A occurs, B happens. A theory is that A causes B. And if we cannot observe A, a theory can assume the existence of A. A then exists in our imagination. For instance, an explanation of electricity assumes the existence of electrons and their supposed behaviour. We cannot see electrons, not even with a powerful microscope. But we can do experiments to see how electricity behaves. We presume the conduct of electricity proves the existence of electrons.

We are imaginative beings. Much of our knowledge involves imagination. Dogs can’t imagine electrons exist, so they will never build an electric car. This discussion of knowledge theory is a historical account. New ideas usually build upon previous thoughts. It discusses Western philosophy as Western thinkers have been the most inquiring. As a result, the scientific revolution started in Europe. Science is the result of thinking but has also greatly influenced thinking. And so, it is the easiest way to tackle the relevant topics.

Classical philosophy

The ancient Greek philosophers speculated about the nature of reality. Some believed everything consisted of fire, water, earth and air. Later on, a few philosophers argued that the building blocks of reality are small particles called atoms. These atoms differ in size and shape. The objects we see are groups of atoms stuck together. Democritus argued the universe merely consisted of atoms in the void. That was already close to the modern scientific understanding of reality. This kind of speculation is called metaphysics.

Metaphysics is about how we see reality. We connect the dots in a particular way. It is our imagination. We can believe that everything consists of fire, water, earth and air, or we can think that atoms are the building blocks of everything around us. It is speculation because these atoms are invisible, and the Greeks had no microscopes. By assuming they exist and have different shapes and sizes, you can explain the presence of various substances. You can also do that by presuming everything consists of fire, water, earth and air, even though we probably find the idea of atoms more convincing.

There were other issues the ancient Greeks were pondering. Some figured that the earth is a sphere. They inferred it by looking at the sea. The sea horizon is slightly curved, while boats disappear in the distance before their sails do. A philosopher named Xenophanes doubted religion. He realised that people believed that the gods were like themselves. For instance, black people thought the gods were black, while red-haired people believed the gods were red-haired. Xenophanes claimed it was impossible to know the gods and how they looked. It was an early form of scepticism.

And why would you worship the Greek gods if the Persians and the Egyptians have other gods? If your place of birth determines what you believe, your beliefs probably are false. The sophists were an early group of philosophers who had come into contact with other cultures. They claimed that absolute knowledge is impossible. Everything is subjective, they argued. This view is called relativism. Socrates is known for his dialogues in which he debated the sophists.

According to Socrates, there is absolute truth even though we do not know it. His pupil Plato later claimed that ideas are the basis of knowledge and that ideas, not objects, are the building blocks of reality. His view is called idealism. It relates to deduction. Plato’s pupil Aristotle asserted that knowledge comes from observations. His approach is called empiricism. It relates to induction. Both methods come with problems. If you imagine a unicorn, you have the idea of a unicorn, and the idealist could claim unicorns exist. On the other hand, if you see a unicorn after eating some mushrooms, the empiricist could also say unicorns exist.

And so, knowledge can always be called into question. If no one has ever seen a unicorn, this still is not definite proof of their non-existence. These creatures could still be hiding deep down in the forests. And perhaps the eating of mushrooms improves your perception. It is for that reason that scepticism emerged. There were two groups of sceptics. The first claimed nothing is certain. They aimed to refute the claims of other philosophers. The second argued it is better to postpone judgment until the matter is sufficiently clarified.

These ideas revived in Europe in the late Middle Ages after the texts of the classical philosophers had turned up in Arab libraries. European philosophers like Thomas Aquinas and William of Ockham were also theologians. They believed that there was no difference between theology and science. Over time, science and religion had a divorce. Their paths separated. Today, science requires empirical evidence. Until now, religion did not.

William of Ockham is known for his simplicity principle named Ockam’s Razor. It states that if several hypotheses can explain a phenomenon equally, the one with the fewest assumptions is the best. Assumptions must all be correct. Ockam’s Razor argues for minimalism in reasoning or preferring obvious explanations if they suffice. For example, if you have ten assumptions with a 50% probability each, the likelihood of all being correct is only 0.1%. The more assumptions you need, the weaker your argument becomes. The argument for this universe being a virtual reality is more potent than this virtual reality being used to entertain an individual we call God, as the first argument comes with fewer assumptions. After all, the latter also requires the assumptions of the former.

Modern philosophy

In 1492, Christopher Columbus sailed to America. Nothing in the Bible or other ancient sources indicates that America exists. Nicolaus Copernicus came up with a theory saying the Earth revolves around the Sun rather than the other way around, which everyone had believed until then. Traditional knowledge had failed dramatically. Copernicus had the luck of dying soon afterwards. A few decades later, Galileo Galilei faced prosecution for claiming Copernicus was right.

At the same time, Protestants began to challenge the authority of the Roman Catholic Church by making religion a personal matter. If you had reason to believe something, it could be correct. That is why we have 45,000 branches of Christianity today. The ensuing religious wars ravaged Europe and ended without a clear winner.

The question arose as to who was right. After all, there can be only one truth. Merely believing something does not make it the truth. But questioning the existence of God remained out of the question. And so, European philosophers sought a rational foundation for religion and tried to base it on verifiable claims. It failed. The effort is commonly known as deism.

The confusion spurred a renewed scepticism and a new search for the foundations of knowledge. Our senses are deceptive, so only rational thinking can generate knowledge, philosophers from continental Europe like René Descartes, Gottfried Leibniz and Baruch Spinoza argued. This school is called rationalism, but it was a refurbished idealism.

In a thought experiment similar to the brain-in-a-vat scenario, Descartes questioned everything the senses register. Your brain could be inside a vat filled with a life-supporting liquid and connected to a computer that generates the impression you are walking. What is beyond doubt, according to Descartes, is that you exist, even when you are just a brain-in-a-vat. And you can establish this fact by thinking. ‘I think therefore I exist,’ he concluded.

Other philosophers like Francis Bacon, Thomas Hobbes, John Locke, and David Hume argued that knowledge comes from observations. It was a renewed empiricism. A philosophical divide emerged between idealist continental Europe and empiricist Great Britain. Later, the United States followed the British tradition.

In continental Europe, thought tended towards the world as it should be, or idealism, while in the Anglosaxon world, thinkers occupied themselves with the world as it is, or empiricism. It is not a coincidence that Karl Marx grew up in continental Europe, and most Marxists of the Frankfurt School come from Germany. They occupied themselves with the world as it should be. In Great Britain and the United States, pragmatic thinking prevailed.

It was an era marked by advances in the natural sciences. These advances were the result of thought. And the advances, in their turn, spurred thinking. It was the combination of observation and thought that led to scientific progress. You can investigate the effect of gravity on the motion of objects. You can do so by dropping an iron ball from a tower. You can release the ball from different heights and measure how long the ball takes to hit the ground. The table below shows the results of these measurements.

Height (in metres)	Time (in seconds)
0.05	0.10
0.50	0.32
1.00	0.45
5.00	1.01
10.0	1.43
50.0	3.19

It requires considerable thought to get the formula representing the relationship between height and fall time: fall time = 9.81 * √ (2 * height). For instance, 3.19 = 9.81 * √ (2 * 50.0). If the tower is only 50 metres high, you cannot measure how long it will take for the ball to fall from 100 metres. With the help of the formula, you can calculate the fall time without the need for measuring it: 9.81 * √ (2 * 100) = 4.52 seconds. It is observation and thinking combined that made this possible.

Finding the mathematical formula that matches the data is like solving a jigsaw puzzle. This way of reasoning is induction. It is about producing a general rule with the help of observations. You can never be sure that the outcome is correct. For instance, using your sightings and with the help of induction, you might conclude that all swans are white. And if you go to the Moon to drop an iron ball from a tower over there, you will discover that the relationship between height and fall time is different.

Another way of reasoning is deduction. It is working from assumptions to conclusions using logic. If the premises are all justified and the rules of logic are correctly applied, then the inference must be correct. Deduction is applying general rules to specific situations. For example, if all humans are mortal (first premise), and Socrates is a human (second premise), then Socrates is mortal (conclusion). Also, if the relationship between height and fall time is fall time = 9.81 * √ (2 * height) (first premise), and the tower is 100 metres (second premise), then the fall time is 4.52 seconds (conclusion).

The scientific method combines thinking, induction and deduction. Simply put, a scientist uses observations and thinking to produce a theory. You need data from those observations to find the formula representing the relationship between height and fall time. Looking at the data alone is not enough. It requires a stroke of brilliance or some puzzling to find the formula. Once you have found the formula, you can use deduction and experiments to check the validity of the formula. For instance, you calculate how long it will take for a ball to fall to the ground from 321 metres. Then, you go to the top of the Eifel tower to drop the ball and measure how long it takes before it hits the ground. If the measurement equals the calculated time, the theory is confirmed.

Kant and Hegel

Immanuel Kant realised that our knowledge arises from observation (empiricism), but we cannot know without thinking (idealism). We interpret observations. That is in our nature. We can count, recognise differences and think of cause and effect. Our thinking imposes its structure upon these observations. If we see a tree, we see branches and leaves. We see that these leaves are green, and those branches are brown. The concept of a tree requires other ideas like branches, leaves, greenness, and brownness. But we view the world through our framework. We do not know reality or the things in themselves (relativism). We do not see trees. These are categories we attach to our perceptions. If we lack words, we don’t observe a tree. Our perspective bends the world. The things themselves remain unknown. Hence, metaphysical speculation about the nature of reality is pointless, for instance, asking yourself whether or not trees, gravity or electrons exist.

Idealist philosophers disagreed. They believed absolute knowledge is possible because the mind creates reality. Reality is subject to our thinking, so our reason can uncover it. For instance, the fall of a ball is subject to mathematical laws invented by the human mind. Thus, you can claim that gravity causes the ball to fall even though gravity exists only in our imagination. The most notable philosopher of this strain was Georg Wilhelm Friedrich Hegel. He argued that we increase our knowledge over time, so there is progress. If we do more research, we can learn more about trees, for instance, how they grow. The more we know, the closer we come to absolute truth. There must be an ultimate answer to the ultimate question of our existence. By decomposing reality into parts and analysing them, you lose the essence of the whole. We are part of reality and interact with it, so we are one with everything around us and history. We can comprehend reality only in this way. And in doing so, we might find the ultimate answer, which is why we exist.

Our understanding begins with observations from the senses. We categorise them into universal concepts like trees, branches, greenness and brownness. We do the observing and the categorising. We usually miss a lot, for instance, the relations with other objects and their history. The tree may have survived a terrible storm, and a pair of doves may use it for their courting and nesting. Hence, our knowledge is incomplete. And, our ideas about objects relate to different objects, so a tree is green because other things are also green. And there are causes. For instance, the tree could be there because a squirrel dropped an acorn when it fled for a fox. By reflecting on our thoughts, we can challenge them. Or reality challenges our beliefs. Something might happen that changes your mind.

Hegel called it dialectic. You can ask yourself, ‘Is the way I look at the object correct or adequate?’ If you don’t know the tree is there because of a squirrel dropping an acorn, your understanding could be inadequate, as you cannot explain why the tree is there. And if someone planted the tree, you can ask yourself why he did it. You can also try to find answers to that. Or you can ask yourself, does it matter why the tree is there? What is the point in knowing about the squirrel having dropped an acorn because of fleeing for a fox? Do I understand the world better if I know that? After we arrive at conclusions, our experiences and thoughts continue. We can come to a different belief later. Hegel saw dialectic as a process. Our knowledge increases. It pushes forward, leading to progress. Hegel’s dialectic has three phases:

1. the initial thought or assertion (thesis),
2. a contradicting or supplementing argument (antithesis, negation),
3. and the integration of the two into an improved insight (synthesis).

Contemporary philosophy

Kant ended the idea that metaphysics can give us knowledge. Philosophers became less ambitious from then on. One reaction was pragmatism. Evolution theory suggests we hold beliefs to survive and reproduce. American thinkers like Charles Sanders Peirce and William James viewed thinking as a means of solving problems. They were not interested in truth or the nature of reality. Another approach, hermeneutics, with thinkers like Wilhelm Dilthey and Martin Heidegger, concerns human communication. Dilthey argued that natural sciences are about interpreting observations while humanities are about understanding meaning. And, Heidegger’s ravings concern the essence of being.

Others embarked upon a renewed search for the foundations of knowledge. Analytical philosophers like Bertrand Russell and Ludwig Wittgenstein believed the main tools of philosophers are language and logic. They aimed to develop a new method to gather knowledge. There is an outside world, and language expresses facts about that reality, or so they argued. This view is called realism, which is related to empiricism. They claimed there are justified true beliefs. For instance, Jane might think that something is true. If this is indeed the case, then her belief is justified.

Karl Popper came up with the idea of falsification. You can never prove that a hypothesis is correct, but you can prove it is wrong when you find contradicting evidence. For instance, you might presume that all swans are white. Once you spot a black swan, your theory is proven wrong. From then on, you assume most swans are white while some are black. It is the way knowledge progresses. The belief that most swans are white and some are black is closer to the truth than all swans are white. It may still be incorrect, as there could still be a red swan somewhere out there no one has ever seen.

Scientific theories are falsifiable. They allow us to make predictions that we can check. For instance, you can go out and look for swans and check their colour. You can use the mathematical formula reflecting the relationship between height and fall time to calculate the fall time from 100 metres. If you do an experiment and the outcome differs from the calculation with the formula, the theory is wrong unless your measurement or computation is in error.

Edmund Gettier criticised the notion of justified true beliefs. You can be correct for the wrong reasons. For instance, Jane looks at her watch. It says it is two o’clock. She believes it. She does not know the timepiece stopped exactly twelve hours earlier. Her belief is thus not justified. The watch accidentally gives the correct time, so her belief is true nonetheless. Likewise, Chief Inspector Clouseau solved his cases by being accidentally correct.

As our knowledge increases over time, our understanding of reality also changes. Scientific discoveries drive these changes. It also applies to science itself. Thomas Kuhn noted there is a succession of paradigms in science. A paradigm is a theory or system of ideas dominating a field in science. Usually, it is not possible to explain everything. The theories that clarify the most phenomena and leave the fewest unexplained are the best and form the paradigm in the field. For instance, the paradigm prevalent in the science of swanology that swans can be black or white is better than the theory that they are all white, even if red swans exist.

If you compare reality to a jigsaw puzzle, the paradigm is the solution that makes the most pieces fit. Unexplained phenomena are pieces without a place in the solution, for instance, unexpected readings on instruments. These readings might indicate that the paradigm is incorrect. When there is no better explanation, most scientists attribute them to errors. At some point, the evidence piles up that the theory is wrong. Then, a scientist comes up with a better hypothesis, and out of the confusion, a new paradigm rises like a phoenix from the dust of confusion.

Paradigms in science affect how we see the world. Only 500 years ago, most people in Europe believed that the Earth was flat, a few thousand years old, and at the centre of the universe. The ancient Greek discovery that the Earth could be a sphere was only known to a few educated people. When Columbus set sail to the West, he expected to end up in Indonesia. Despite the efforts of flat-earthers and creationists, most people today believe the Earth is a sphere, billions of years old, and an insignificant dot in the universe.

The evidence contradicting existing religions and the failure of ideologies gave rise to post-modernism. Post-modernists claim that great stories like religions and ideologies are dead and absolute knowledge is impossible. Words like reality and truth are totalitarian concepts, they argue. There is only room for small stories, lived experiences, and perspectives. A great source of inspiration was Friedrich Nietzsche. He proclaimed the death of God and heralded the end of the Christian story of God’s people on the road to Paradise, which gives meaning to our existence. And suddenly, we were out there, without God, condemned to give meaning to our petty existences ourselves. Post-modernism is relativism with a new marketing campaign. This view was, not surprisingly, criticised by those who claimed the truth is out there somewhere lurking.

And so we are more or less back at the point where Socrates refuted the sophists. With the simulation hypothesis, speculation about the nature of reality or metaphysics re-emerged. That lurking truth might surprise us still. We could all live inside a computer simulation run by an advanced post-human civilisation. It seems that knowledge theory has gone nowhere. At least, it is clear that while our knowledge grew dramatically during the last 2,500 years, knowledge theory did not progress accordingly.

Data, information, knowledge and wisdom

There is a difference between data, information, knowledge and wisdom. Data refers to signals or symbols like letters or numbers. Data does not need to have meaning. A noise you hear is data. The sequence Q&7nn?9Y is also data. Information refers to what data means. You have information if you know the noise you hear comes from a car engine. There is a car with a running engine nearby. Characters together can form words and sentences that can have meaning if you know the context. So, if you read sales were up 25% last month, this can be information, but only if you know the corporation it applies to.

To acquire knowledge, you need information, and it needs to be correct. You may read sales are up by 25%, but it does not have to be true. And the noise you hear might be a recording. Wisdom refers to understanding. Knowledge itself does not always lead to better insights and decisions. It can be hard to discern between the important and the insignificant. You may turn indecisive when information appears to conflict. Alternatively, you might ignore information to become decisive.

The amount of data used and stored is growing fast. Most data is not information but entertainment, for instance, cat videos on YouTube. A small portion may be information like sales data. Whether or not data is information depends on your objective. If you are looking for the meaning of life, sales data is not information. For any investigation, only a fragment of the available data is relevant. It requires wisdom to understand which data is helpful and what it means for the inquiry. The amount of data increases faster than the amount of information. The amount of information increases faster than knowledge. And wisdom can’t be measured at all.

Proof and evidence

There is a difference between proof and evidence, even though we use these words interchangeably. The definition of proof is a final verdict that removes all doubt, whereas evidence supports a particular explanation. Proving is usually done by deduction, while induction works with evidence. Proof requires the premises to be correct, which is problematic because the premises used in deductive reasoning, for instance, the relationship between height and fall time, are often attained by induction. In mathematics, proving is possible. It is pure deductive reasoning without applying it to reality. For instance, 1 + 1 = 2 is always true. But if you think you see two trees, someone else may not agree. Perhaps, the other person sees three trees or only bushes.

The concept of evidence relates to empiricism. Only, you may not have all the information. With a limited sample of swans and induction, you could conclude that all swans are white. We support claims about reality with evidence, for instance, experiments, but we cannot be sure that relationships like those between height and fall time are always the same. Hence, there is no proof in reality, not even in science, but scientific evidence meets specified quality standards. The scientific method involves careful observation and rigorous scepticism because observations involve our fallible senses. It further includes formulating hypotheses via induction based on the observances. It is followed by testing deductions made with the theses using experiments and measurements.

The words establish and conclude can bridge the gap between proof and evidence. They denote achieving the best explanation for the observations. The observations need to be reliable. However, it may be impossible to use a theory like this universe being a simulation to make testable predictions. A hypothesis needs evidence and must explain the observations better than the alternatives. Assuming this universe is a simulation, we can explain paranormal events. Rigorous scepticism would be filtering out paranormal events that do not have multiple credible witnesses or have other plausible explanations.

Excessive scepticism is ignoring evidence of paranormal events or giving implausible explanations like delusion in the case of multiple credible witnesses. The simulation hypothesis can explain the paranormal in cases where claims of fraud and delusion fail to be convincing. The main difference is that it does not allow us to make predictions we can subsequently test in experiments. Paranormal phenomena are unpredictable, so the simulation hypothesis is not science but metaphysical speculation.

Takeaways

Science cannot prove this universe is a virtual reality. It may still be possible to establish that we do with the help of metaphysical speculation. That requires understanding the nature of our knowledge, hence knowledge theory. So, here are the takeaways from the previous discussion:

• We can always question assertions because the methods to arrive at knowledge, thus induction and deduction, can lead to wrong conclusions.
• The validity of a statement depends on whether it accurately describes (some part of) reality. With the help of empiricism and induction, you might arrive at better conclusions.
• The truth or falsity of a system of statements depends on its logical consistency. Contradictions are evidence of errors. With the help of idealism and deduction, you might arrive at better conclusions.
• An assertion is plausible when sufficient evidence supports it while no evidence contradicts it. In science, it means no one has falsified the theory yet.
• Pragmatism implies usefulness is more important than truth. For instance, religions make large-scale cooperation possible.
• Minimalism argues for using as few assumptions as possible to establish a point. Assumptions are always questionable. It prompts us not to engage in unnecessary speculation or to use irrelevant data. That is why this booklet is thin.
• There can be progress in thought. Contradicting arguments can be correct in their own right as there could be a higher level of truth or synthesis resolving the contradiction. For instance, the simulation hypothesis may resolve the contradiction between the religious idea of creation versus the Big Bang and evolution theories.
• Proof means the absence of doubt, which is impossible in dealing with reality. Evidence can only support a particular explanation or theory. Without proof, one can look for the best explanation for the observations.

Quality of the evidence

I have verified the materials presented as evidence and tried to ensure my sources are reliable, but there may still be errors. Recently I discovered that a 1994 Vice Magazine issue featuring Beavis and Butthead dressed as Al Qaeda operatives flying planes around the Twin Towers was a prank. It would have been an eerie coincidence otherwise. You can expect a magazine named Vice to make such jokes.

Latest revision: 23 March 2024

Featured image: Owl eyes. Brocken Inaglory (2006). Public domain.

Other images: Brain-in-a-vat. Alexander Wivel (2008). Public domain.