Knowledge by Jennifer Nagel [Book Summary – Review]

It is famously said that knowledge is power. However, we can also be confused by the knowledge nowadays. Each day of our lives we are exposed to information. Part of it tells the truth. Part of it is illusory. Most of it is completely incorrect. Although humans circuit filtered knowledge within their political and social circles, they seldom avail knowledge that is not in these circles.

It is probably the time to question our current knowledge or how much knowledge we assume we have. Epistemology presents us with a great point of departure which enables us to criticize all we know. As a philosophical field, it examines how knowledge as a concept is created, circuited, and grasped. The chapters below summarize pivotal concepts in epistemology.

Throughout the chapters below, you will imbibe  

  • through which complicated ways belief establishes a connection with knowledge;
  • the mysterious aspects of mind reading; and
  • the ambiguous status of our knowledge about Mount Everest’s ranking as the highest mountain on our planet

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Chapter 1 – Although “to know” is not complicated as a verb, what it means is sophisticated.

Today, it is not hard to acquire knowledge of something. Media works all day and the internet is quite easy to reach. However, accessible knowledge is mixed with propaganda and notions. It is only normal to be curious about which information is which in a century of too much information. Dig deeper and deeper and so you shall end up asking more complex questions such as the meaning of knowledge and how humans know what they know.

The questions above are at the core of epistemology, the field of philosophy whose specialty is studying knowledge.

Below, some points need to be made clear about knowledge. 

Firstly, humans cannot acquire the knowledge as if it is a resource like an ore or fossil fuel that is existent. The one who knows creates it. Picture yourself shaking a metal coin in a tin. The head side appears upwards. This is what happens. Still, if someone does not take a glance at the inside of the tin, this reality cannot be counted as knowledge since it is not known. A fact becomes knowledge emerges if we reach that fact. 

In the second place, knowing the truth and believing that it is the truth are not the same things. Although it seems straightforward, the question of how we can understand whether we only believe or know comes to the fore. Some skeptics argue that we cannot distinguish between the two, or even that there is no distinction between these two: knowledge is merely a label attached to the notions of specific educated people, such as scientists and CEOs. Asserting that we can, and definitely, oppose even the knowledge of professionals is a more fruitful method. Moreover, all people can know. Frequent usage of “to know” as a verb in the English language is not groundless.

In this the issue becomes seriously comprehensive: Humans can merely reach knowledge of things which they are sure that these things are not lies. However, which person is to explain what the truth is? Many philosophers assert that truth is not subjective and so its reality cannot change from person to person. Nevertheless, Protagoras, a Greek philosopher who lived in the fifth century, did not think in this way. He argued that the truth is not objective. When two people stand amid the wind, the first one can say it is warm while the second one can tell it is cold. And they can be equally confident about their knowledge.

However, if we were to take the idea of Protagoras to its logical conclusion, we would have to say that all individuals are never wrong about things that they do not doubt are true, and no human being is wrong. Thus, to question knowledge ever and ever again let us agree with Plato and many other philosophers who are convinced that the argument by Protagoras is not right and the truth is not subjective; it is a presence that is not bound to any individual self. 

Chapter 2 – Skeptics think that there is a possibility that humans do not know what they assume they know.

Well, now, just put Protagoras’ arguments aside and imagine that you only know things that are certain to be true. Moreover, by the view of the dominant philosophy, let us take for granted that the truth is the same for everyone and exists independently of us. Imagine a real electrical outlet: Acquiring information depends on plugging it into this outlet.

However, is plugging into such an outlet possible for us to do? A skeptic may give a  negative answer.

Here’s a kind of thinking exercise: Do you have shoes on your feet now? The answer may seem obvious to you. However, how can you be sure that you know? For example, what if you are dreaming? Thinking with this method may seem like unnecessary confusion. But this is exactly the way skeptical thinkers obtain information. And in this method, even a fact that seems very simple from the outside turns into a dubious thing.

Skepticism in philosophy was created in ancient Greece, which was home to two main schools of skepticism. It was the Academic school that argued that it was not possible to know something. Pyrrhonians, on the other hand, just did not want to come to any conclusion. The Stoic understanding of the nature of knowledge before the advent of these two schools is the basis of them. The Stoics drew a line between impression, or what you perceive, and judgment, which is your decision to accept or reject what you perceive. A friend coming towards you creates an impression. However, is such an impression correct? Could this person just be someone who looks a lot like your friend? Thus, the Stoic philosophers argued that only impressions with certainty of truth should be accepted. This means that you have to decide after the distance between you and that person becomes short enough to understand whether the person coming towards you is your friend or not. 

Although scholars agreed with this theory, they did not accept the notion that every impression may well be true without doubt. There is a possibility of seeing hallucinations. Maybe that friend of yours has an identical twin. We cannot know even the things we think we know well.

The level of the Pyrrhonian school’s skepticism is even higher. According to those thinkers, the Academic skeptics’ argument that knowledge cannot be surely verified in any way itself was a kind of knowledge. They rejected asking themselves if humanity could ever acquire knowledge. They rejected coming to any kind of conclusion in anything. They think being open-minded in all subjects is a virtuous act. To keep his skeptic friends on the road of suspicion, Sextus Empiricus, a famous Pyrrhonian skeptic, went as far as coming up with slogans such as “I determine nothing” and “Perhaps it is, and perhaps it is not.”

If we used the method of the Academic skeptics, this debate on knowledge would not continue further. In the meantime, the Pyrrhonian skeptics would state that the discussion should not be finalized. Fortunately, various other leading philosophers handle the issue pretty differently.

Chapter 3 – Two novel understandings of knowledge progressed thanks to two theories, Descartes’ rationalism and Locke’s empiricism.

Recall the way skeptics assumed that humans can know nothing. Every thinker does not think like that. Rene Descartes and John Locke are two deep thinkers who have counter-arguments.

Under the umbrella of early modern philosophy, Descartes and Locke were the most prominent figures of the seventeenth century. Both thinkers effectively contributed epistemology by debunking the beliefs of skeptical philosophers that knowledge was something that could not be obtained and that it was inaccessible. However, they did not agree on every single point.

Quite unlike the skeptics, Descartes, as a rational thinker, thought that an individual could understand the most basic truths. Most fundamentally, he argued in his Meditations dated 1641 that: A man can be sure that his existence is real. Descartes does not doubt God’s existence. He inferred that the idea of God is equivalent to the idea of pure excellence. Pure excellence, as an idea, could not originate from a root with defects, namely, humans.

To Descartes’ mind, we have the knowledge that God and the self exist. In reality, Descartes thought that we innately grasp the existence of these things, as well as other rational and intangible concepts such as numbers, mathematics, geometry, and actuality itself. Long story short, the being called human is born with many fixed facts.

Although Locke agreed with the particular arguments of Descartes, he did not agree with his high ideas about human children. After all, do we act as if we were born with rational thoughts? For instance, Locke did not think that babies emerged from their mothers’ wombs equipped with rational guidelines.

Locke believed that we acquire ideas by sensing. A human being is exposed to all kinds of sensations in infancy, and by repeating these sensations we organize them step by step into patterns and understandings. As we learn to observe the workings of our mind, we develop the power to think from what we sense in the early years of our lives. According to Locke’s theory of empiricism, sensation, and reflection are from the foundations of human knowledge.

However, Locke also accepts that the sensations and reflections experienced by each person are different. For Locke’s way of thinking, Descartes’ idea that we all understand things such as love or justice with no difference was not valid.

Chapter 4 – The relationship between what we believe and what we know is as all-important as it is shifty.

Let’s pursue Locke’s way of thinking a bit more. If we affirm what Locke put forth, which is different from Descartes’s opinion, what we know does not come at birth and so the circumstances that make us acquire knowledge of this and that become even more and more complex.

After centuries passed, in the 1960s, classical analysis was introduced to elucidate these circumstances more accurately. Components in this analysis hold that a person can fully know a proposition as long as the proposition is occurring, as long as the person puts faith in the proposition, and the subject is justified in her conviction.

To give an example, one of Bertrand Russell’s famous philosophical riddles is as follows: 

A person is running to avoid missing his train. Does he have enough time? He glanced at the station clock. It shows 13.17. It is his reality and justified conviction that the time is 1:17; therefore he knows the time. However, what if the clock is faulty and it is in reality 13:33? Can such a man “know” that it is 1:17? Not at all. He is acting on a conviction that is not true.

Regardless, classical analysis has an issue, which proposes that knowledge cannot arise from a wrong conviction. Imagine a detective collecting proof to demonstrate that a woman was murdered by her husband. Since the detective has the pistol and fingerprints of the perpetrator in question, there is no need to even include the statements of several eyewitnesses. The detective rightly concludes that the man murdered his wife. However, one of the eyewitnesses is giving false testimony. So does this mean that the detective’s knowledge is no longer valid because it is based on a wrong conviction? Philosopher Edmund Gettier doesn’t think so. This example shows that we can know even if some of the beliefs that assist knowledge are far from true.

As we can see from Gettier’s example, the classical analysis of knowledge has weaknesses. However, can it be done this way? Alvin Goldman put forth his theory of causal knowledge, which eschews “true” or “false” conviction, to argue that there must be a cause-and-effect relationship between conviction on a fact and reality of a thing. Suppose, you see a building engulfed in flames, the knowledge you have gained through experience about what this event is and how it progresses will establish a causal link with the fire you are currently seeing. However, this is not true either. To conduct the skeptics, we can pose the following question: What if the building you think is in flames is in reality a quite realistic three-dimensional moving image?

From the 1960s to the present, epistemologists have had a hard time examining and explaining the link between belief and knowledge. Many are skeptical about the veracity of this connection. Although there is no clear method to clarify this, examining this relationship in depth continues to create a further comprehension of how we can know what we know.

Chapter 5 – Epistemology questions everything, without excluding the fundamental phenomena.

As we saw in chapter four, after Gettier problematized the classical analysis that knowledge comes from true conviction that is proved right, Alvin Goldman suggested the causal theory of knowledge. Goldman’s theory falls within a larger section of epistemological theory called externalism.

We can probably explain externalism through the example of Mount Everest, the highest point on the planet Earth. How do you know of this? If you did not learn this fact during, for instance, your first kiss, you will not recall exactly how you gained such information. You have obtained it from many sources so you do not doubt its accuracy. Externalists say you know that Everest is the highest point on our planet.

At this point, there is trouble in the Everest example. Externalists argue that knowing this is true is enough to connect it with the fact that this is the highest mountain on Earth. However, many people have a connection with the “fact” that Australia’s capital is Sydney, although Canberra is the capital. It is not difficult to be in an erroneous relationship with a real situation or event.

Currently, internalist thinkers are on a different path than the ones above. They follow the idea that “seeing equals believing”. Supporting proof is a prerequisite for knowing. Have you compared Everest with other mountains on our planet? Is there a method you can use to measure its unsurpassed dimensions? Is it not? So, you just called your conviction that Everest is the highest mountain “knowledge” without knowing whether it is so.

Long story short, while externalists argue that we can reach knowledge of something certain without proof, internalists argue that such a thing is out of the question. This does not mean that internalists state that we ought not to conceive Everest as the Earth’s highest mountain. We ought to for the sake of every intention and aim! Just out of philosophical curiosity, we have to ask ourselves whether this is something we can know. 

However, this does not mean that internalist thinkers believe that knowledge can never be accessed. They highly value first-person thinking, carried out in an orderly manner. They argue that with the skill of making inferences, perceiving with the senses, and thinking humans can master the knowledge of many things. Humans can find out what we had for dinner the day before by reflecting on our behavior and looking at our shopping receipts.

Although externalist thinkers have faith in the strength of first-person thinking, they enjoy accepting the results of thinking automatically as knowledge, which means that it is enough to know that the Pi corresponds to roughly 3,14 without understanding the mathematics behind it.

Chapter 6 – Testification is a mode of knowledge that splits epistemologists.

Both the internalist thought system and the externalist one accept first-person thought as a reliable source of knowledge, although there are different versions. So what happens when we look at the issue from a different perspective?

It is an undeniable truth that we mostly learn information about the environment we live in from other people rather than obtaining it first-hand. We learn about the lives of the ancient Romans through what we read. Thanks to mass media, we know what’s happening on the other side of the planet because we can read about it. We know about events happening on the other side of the world because we see them on the news.

However, can this kind of testification, that is, second-hand testification, be considered a type of knowledge?

We mentioned John Locke above if you recall. He believed that knowledge was achieved through perception. Therefore, he argued that what we hear from another individual never offers us anything that can be truly known. Locke’s point is extremely strict. Although we presume that there was a thinker called John Locke who lived in the seventeenth century, to Locke’s mind, we cannot be certain.

Another group, reductionist philosophers, tried to generate a conciliatory view. They argue that humans are equipped with critical abilities such as inference, memory recording, and perception which is Locke’s most beloved one. We can evaluate these abilities thanks to the reliability of testification and the information it has. Even though perception continues to be the pivotal ability in this thinking method, humans can also state that Mars exists without the need to go there.

Some philosophers are not in the same line as Locke, quite the contrary. They think that witnessing is a form of knowledge in itself and that humans can access it independently of other forms of knowledge such as perception. However, there is one condition: The words of the person whose statement was taken must convey the truth.

The interesting point is that in this understanding, the prerequisite for the person giving information not to be a liar is not for him to believe the information he provides. The truth can be given to us from an imperfect source, for instance, a teacher who believes that the creation story reveals the beginning of humankind has to explain the theory of evolution to his pupils.

A source with flaws may also be open to collaborating with other people. Let’s say you are at a dinner party dinner where a conversation comes up about the world’s best-selling music albums. Your companion may have an intuition that Thriller by Micheal Jackson is the best-selling album in history and can prove to be accurate by checking it on, sayMoreogleneededsufficient for Locke, who claims that we can merely say that Thriller is the best-selling album on our planet. Yet unless your dinner companion is a follower of John Locke or a supporter of reductionists, this check on Google should calm down such disputes at the dinner table.

Chapter 7 – The context determines the knowledge.

Some epistemologists are interested in whether second-hand testification can be considered knowledge, or whether we can know something when our knowledge is based on a false belief. However, there is a movement of thought that destroys these questions: contextualism. As obvious from its name, it asserts: The context determines every single thing.

Picture a father going to the zoo with his daughters. He points to an animal with black and white stripes that looks like a horse and shouts with excitement to his children that it is a zebra. Thus how is he so sure that this zebra is not a donkey painted in black and white? Relevant alternatives theory suggests that, in the context of a properly maintained zoo, the idea that the creature is a donkey painted black and white is not a good alternative to the idea that it is a zebra. There may be another story in a dicey small floor show. Alternatives that are fitting to this are not independent from the context.

Contextualism, which develops the theory of relevant alternatives, argues that the standards we have for knowledge are subject to context.

These standards are applied differently in different situations. A basketball player who is 1.93 meters tall may present himself as tall on his online dating profile. Now he applies broad standards: broadly, he is roughly 1.93 meters tall. A sports commentator making comments on the same basketball player might say that he is not quite tall. The commentator does not necessarily have to be wrong. Not by the more stringent height standards among professional basketball players.

Contextualism enables an ordinary individual and a skeptic to be present at the same time. An ordinary person who has nothing on his feet may say that he is aware that he has no shoes on. A skeptic who has nothing on his feet may ask how he can be sure whether he is wearing shoes or not. He may claim that there is a possibility that he is living in a dream where he sees himself as barefoot. The contextualist would advocate that both the normal person and the skeptic tell the truth and that they simply assign different standards to the concept of knowing. 

After all, even a contextualist cannot ensure that every person is satisfied. Some philosophers believe that knowledge, and therefore truth, does not change from person to person or from case to case. These thinkers assert that contextualism is an extreme thought. The following thought we examine may be more extreme.

Chapter 8 – We can sense the knowledge of other people.

We haven’t talked about it yet, but there is another way to gain knowledge. Even though you always use it, you don’t realize it. This is called intuiting something.

Consider it. If your friend Sam tells you that he is a candidate for a new position at work, you can convey this by saying that Sam knows he has been accepted for the job. Then you may say that Sam thinks he has been accepted for the job. You do not have to worry about which verb to use. There is no point in doing such a thing, as we can subconsciously sense the things others know, the issues they are not sure about, and the points they do not know on many occasions.

Reading minds is quite an extraordinary skill that we can do thanks to our intuition. We are not doing this with any Las Vegas-style illusionist trick. We cannot know every word that goes through people’s minds. Sensing the mental states of others epistemologically means mind reading. We can intuit what those around us know through subconscious deductions. 

In this regard, humans are like most animals. Chimpanzees utilize mind reading to see if enemy chimpanzees have found places where they store food. Although chimpanzees track each other on knowing or not knowing something, only humans can exploit sensed ignorance. For example, we can do this exploitation via pranks. When we hand a close acquaintance a tin of peanuts that contains a plastic toy snake, we take advantage of the fact that this person does not know what is inside the tin.

Although the human skill of intuition of knowledge is dazzling, it is not limitless. Humans can track a couple of states of mind simultaneously. For instance, we can sense Rhonda’s thoughts that John is aware of her current relationship with another person. Further, we can sense that John thinks that Rhonda supposes that John is aware of her relationship. However, we are prone to reach the peak when others want us to track more than half a deck’s states of mind.

Humans are also self-centered. It is not easy to exclude what we know when sensing what another person knows. It has been demonstrated that when two individuals are doing a stock trade if one of them has insider information, the one who is equipped with more knowledge has a hard time foreboding how his rival will do such a business. The one with insider knowledge flounders in taking that knowledge from what he knows about the knowledge of his rival.

Even though it has endpoints, our skill of sensing demonstrates how knowledge forms bonds among people and how people create bonds among themselves through knowledge. Even now epistemologists struggle with the idea which asks what knowledge is. However, they do not refuse to accept the fact that knowledge is in the heart of humans’ very selves, their relationships with each other, and their perception of the world.

Knowledge: A Very Short Introduction Jennifer Nagel Book Review

Knowledge is not a fixed subject, and it seems that even the experts do not have a consensus on what constitutes knowledge or how we can obtain it. However, questioning how we know something we know and whether we know what we think we know encourages us to judge the knowledge we have gained, the knowledge we have accepted without any question, and the thoughts we retain by passing them through the filter of criticism. 

Avail the force of society’s knowledge. 

A knowledgeable person does not have to be an expert himself. An ensemble may have broader collective knowledge than the individuals that make up that ensemble. For instance, in an orchestra, the trumpeter knows how to play pieces written for the trumpet, and the oboist knows how to play pieces written for the oboe. However, in an ensemble, we know how all symphonies should be performed since that ensemble is a collective.

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