The Meaning of Knowledge: Crash Course Philosophy #7

Summary

This Crash Course Philosophy episode delves into the nature of knowledge and belief. It clarifies the philosophical definitions of 'knowing', 'believing', 'proposition', and 'justification'. The traditional view of knowledge as justified true belief is challenged by Gettier's influential counterexamples, which suggest that knowledge requires more than just true, justified beliefs. The episode also explores the concepts of assertions, propositions, and propositional attitudes, highlighting the complexity of philosophical debates on knowledge.

Takeaways

• 📚 Philosophers have specific definitions for terms like 'knowledge', 'belief', 'proposition', and 'justification', which are essential for understanding their debates.
• 🤔 The nature of knowledge is complex; philosophers argue that it's not just about being correct but also about having justification for one's beliefs.
• 📝 An assertion is a linguistic act with a truth value, which can be true, false, or indeterminate, depending on the context.
• 📖 A proposition is the underlying meaning of an assertion, and it remains constant regardless of the language in which the assertion is made.
• 🧐 Propositional attitude refers to a speaker's mental state towards the proposition they are asserting, such as belief or disbelief.
• 🐱 Belief is defined as taking a propositional attitude of truth, meaning one thinks the assertion corresponds to reality.
• 📖 The traditional definition of knowledge is 'justified true belief', which has three components: belief, truth, and justification.
• 🔍 Justification can come from various sources, including testimony from experts or first-person observation through the senses.
• 🕵️‍♂️ Edmund Gettier challenged the traditional definition of knowledge by proposing cases where one can have a justified true belief without actually having knowledge.
• 🐑 Gettier cases, such as mistaking a dog for a sheep in a field, demonstrate situations where one might be correct by accident, not through knowledge.
• 💡 The philosophical debate on the definition of knowledge continues, with Gettier's work prompting a reevaluation of what constitutes true knowledge.

Q & A

What is the main theme of the Crash Course Philosophy episode discussed in the transcript?

The main theme of the episode is the exploration of the concept of knowledge, specifically the philosophical definitions and debates surrounding beliefs, assertions, propositions, and justifications.

What does Squarespace offer according to the transcript?

Squarespace offers a platform to create websites, blogs, or online stores, enabling users to share their passions with the world without the need for coding skills.

What is the traditional definition of knowledge in philosophy as mentioned in the script?

The traditional definition of knowledge in philosophy is 'justified true belief,' which consists of three components: belief, truth, and justification.

What is an assertion in the context of the script?

An assertion is a linguistic act, either spoken or written, that has a truth value and asserts something about the world, which can be either true, false, or indeterminate.

What is the difference between an assertion and a proposition according to the script?

An assertion is the act of stating something with a truth value, while a proposition is the content of the assertion, representing the underlying meaning of what is being said.

What is a propositional attitude as described in the script?

A propositional attitude is the speaker's mental state towards the proposition they are making, such as belief, disbelief, or uncertainty.

What does the script suggest about the nature of beliefs?

The script suggests that beliefs are a kind of propositional attitude where one takes a stance on the truth of a proposition, and it's possible to have false beliefs that do not correspond to reality.

What is the significance of Edmund Gettier's contribution to the philosophy of knowledge as mentioned in the script?

Edmund Gettier's contribution is significant because he challenged the traditional definition of knowledge with his Gettier cases, showing situations where one can have a justified true belief but not actual knowledge.

What are Gettier cases as introduced in the script?

Gettier cases are hypothetical situations proposed by Edmund Gettier that demonstrate instances where someone might have a justified true belief but lack knowledge, thus challenging the 'justified true belief' definition of knowledge.

What is the role of justification in the traditional definition of knowledge?

Justification in the traditional definition of knowledge is the evidence or support for one's belief, which is necessary to transform a true belief into knowledge.

How does the script illustrate the concept of justification through testimony?

The script illustrates justification through testimony by explaining that much of what we know is learned through taking others' words as evidence, such as from teachers, books, and news reports.

What is the final verdict on the cat's behavior in the script?

The final verdict is that the cat did not pee on the desk, as it was unable to spend any time on the desk, making the initial assertion about the cat's behavior false.

Outlines

00:00

📚 Introduction to Knowledge and Belief in Philosophy

This paragraph introduces the topic of the video, which is the philosophical exploration of knowledge and belief. It discusses the importance of definitions in philosophy and how terms like 'knowledge', 'belief', 'proposition', and 'justification' are used with specific meanings. The paragraph sets the stage for a deeper dive into these concepts, hinting at the complexity and ongoing debates among philosophers. It also humorously introduces the idea that philosophical arguments are more nuanced than typical disagreements, and that understanding the nature of assertions and propositions is crucial for engaging in philosophical discourse.

05:03

🔍 The Nature of Assertions, Propositions, and Beliefs

This paragraph delves into the specifics of what constitutes an assertion, proposition, and belief in philosophy. An assertion is defined as a linguistic act with a truth value, which can be true, false, or indeterminate, especially regarding future events. Propositions are the underlying meanings of assertions, which remain constant regardless of the language used. The paragraph also explains the concept of propositional attitudes, which are the speaker's mental states towards the propositions they make, such as belief or disbelief. It further clarifies the definition of belief as taking a propositional attitude of truth, meaning that a belief is held when one thinks an assertion corresponds to reality, even if it's incorrect.

Keywords

💡Assertion

An assertion is a linguistic act, either spoken or written, that has a truth value, meaning it can be either true or false. In the video, an assertion is exemplified by the sentence 'This is a cat.' Assertions are contrasted with questions, which do not assert anything.

💡Proposition

A proposition is the underlying meaning of an assertion. It remains constant even if the assertion is made in different languages, such as 'This is a cat' and 'Este es un gato.' A proposition is true if it corresponds to reality, which is central to the video's discussion on truth and knowledge.

💡Justified True Belief

This traditional definition of knowledge states that for someone to know something, three conditions must be met: the belief must be true, the person must believe it, and there must be justification for the belief. The video discusses how this definition was widely accepted until challenged by Gettier cases.

💡Gettier Case

A Gettier case is a scenario where someone has a justified true belief but does not actually have knowledge due to the justification being flawed. The video explains Gettier's challenge to the traditional definition of knowledge with examples like Smith and Jones applying for a job.

💡Propositional Attitude

A propositional attitude is the speaker's mental state towards the proposition they are making. For example, believing 'This is a cat' indicates a propositional attitude of belief. The video explains that attitude affects whether a belief is genuine or not.

💡Truth Value

Truth value refers to whether a statement is true, false, or indeterminate. The video uses the example 'This cat will pee on my desk before the end of the show' to illustrate how assertions about the future have indeterminate truth values until the event occurs.

💡Testimony

Testimony is a form of justification based on taking someone else's word for something. The video highlights that much of what we know comes from testimony, like teachers' teachings or news reports, which we accept as justification for our beliefs.

💡First Person Observation

This type of justification involves acquiring information through one's own senses. The video mentions identifying a cat based on its appearance and behavior as an example of first-person observation used to justify a belief.

💡Belief

Belief is when someone takes a propositional attitude of truth towards an assertion. The video explains that belief is essential for knowledge but distinguishes between true beliefs and justified beliefs, illustrating how false beliefs can still occur.

💡Knowledge

Knowledge is traditionally defined as justified true belief. The video discusses how philosophers have debated this definition and how Gettier cases challenge the idea that having justified true belief is sufficient for knowledge.

Highlights

Philosophers have specific definitions for terms like 'know', 'believe', 'proposition', and 'justification'.

Philosophers argue over these terms even after defining them, showing their nuanced nature.

The distinction between knowledge and correctness, and the role of justification in belief.

The importance of understanding the difference between an assertion and a proposition in philosophical debate.

An assertion's truth value represents its state of being true, false, or indeterminate, not its correctness.

The content of an assertion is called a proposition, which holds meaning regardless of language.

A proposition is true if it corresponds to reality, as in the example of identifying a cat.

Propositional attitude reflects a speaker's mental state towards the proposition they assert.

Belief is defined as taking a propositional attitude of truth, as in believing something corresponds to reality.

The concept of false beliefs and the distinction between belief and truth.

The traditional definition of knowledge as justified true belief, with three separate components.

Forms of justification, including testimony from experts and first-person observation.

The impact of Edmund Gettier's paper challenging the justified true belief definition of knowledge.

Gettier cases, which demonstrate situations of justified true belief that do not equate to knowledge.

The ongoing philosophical debate post-Gettier about the definition of knowledge.

The practical application of these concepts in understanding belief and knowledge in everyday life.

The episode's conclusion that leaves the audience with questions about the true nature of knowledge.

Transcripts

Crash Course Philosophy is brought to you by Squarespace.

Squarespace: Share your passion with the world.

You probably think you know a lot of things.

But do you know what it means to know something?

We’ve spent quite a bit of time discussing beliefs and knowledge, but we haven’t really

been specific about what we mean when we talk about those things.

Thankfully, philosophers love a good definition. They have very specific and lucid ideas in

mind when they use terms like know or believe or proposition or justification.

And, about ten minutes from now, you too will know what you’re really saying when you use those words.

But, just because these terms have been defined, doesn’t mean that philosophers aren’t still arguing over them.

Because you know, that’s how philosophers do.

Their definitions might seem kind of obvious at first, but the more you think about them,

the more nuanced they turn out to be.

Like, is having knowledge of something the same thing as being correct?

Or, if you believe something to be true, and it is true, does it matter if your belief in it is justified?

And can you be right about something without really trying?

Answers to these questions and more await you, as well as

cats!

[Theme Music]

So you’ve heard this already: Philosophers love a good argument.

But you’ve figured out by now that philosophers argue in a different way than, like, kindergarten

kids, or Internet trolls, or other people who confuse “arguing” with sniping back

and forth or just thinking up witty comebacks.

Nope. Philosophers have all kinds of rhetorical devices at their disposal that they can use

to advance an idea, or call into question the ideas of their interlocutors.

So in order to hold your own in a philosophical debate, you’re gonna have to know the difference

between two things that sound like exactly the same thing: an assertion, and a proposition.

And you’ll need to be able to tell whether someone actually knows what they’re talking

about, or if they just believe what they’re saying might be true.

For example: The sentence I’m saying right now is an assertion. An assertion is a linguistic

act – either spoken or written – that has a truth value. And despite what it might

sound like, truth value isn’t a measure of how right something is. It’s just the

state of being either true, or false, or indeterminate. All declarative sentences have truth values.

Declarations that assert something about the past or present are either true or false.

And assertions about the future are indeterminate, at least when they’re expressed, because

no one knows if they’re right or not yet.

For example, I’m gonna assert that “This cat will pee on my desk before the end of the show.”

That assertion has a truth value, but it’s indeterminate, because the show’s not over yet.

We’re just gonna have to wait and see.

Now, all of this contrasts with other kinds of linguistic acts, like questions, which don’t assert anything.

“This is a cat” is an assertion, as opposed to “Is that a cat?,” which is a linguistic

act, but not an assertion.

But the substance of what you assert has a name, too.

The content of your assertion is your proposition. It’s the underlying meaning of what you’re saying.

So even though an assertion itself can change, depending on say, what language it’s spoken

in, its meaning doesn’t change just because its outer packaging does.

Like, “This is a cat” and “Este es un gato,” both assert the same proposition.

And a proposition is true if it asserts a claim that corresponds to reality.

The proposition when I assert “This is a cat,” is true if the object of the “this”

is in fact a cat, and false if it is anything other than a cat. Like, “This is a cat.”

It’s worth pointing out that attitude counts, too, when you’re asserting something.

A speaker’s mental state toward the proposition they’re making is their propositional attitude.

If I say, like, “This is a cat,” but I actually believe it to be a rat and I’m

trying to fool you, then philosophers would say that I have a propositional attitude of disbelief.

Whereas, if I think I’m speaking truthfully, I have a propositional attitude of belief.

And of course, you’re not going to get very far as a philosopher unless you understand

the classic definition of belief itself. Based on the lingo you’ve learned so far today,

belief is just when you take a propositional attitude of truth.

I believe that this is a cat, if I think it’s true – that is, if my attitude is that the

assertion corresponds to reality. And even if I’m wrong -- even if there were an aardvark

on my desk, or if there weren’t a cat on my desk at all, which there isn’t anymore

-- if I really thought there was a cat on my desk, that would just be my belief.

My propositional attitude, in other words, is what determines if I have a belief.

What all this means is that I, like everyone else, can have false beliefs. Simply thinking

something doesn’t make it correspond to reality, which is what’s needed for truth.

But of course, the fun of arguing is showing off what you know to other people, or at least

producing really clever evidence to support your case.

So, this raises the question of what it means to actually know something, in the philosophical sense.

The traditional definition of knowledge is that it’s a justified true belief.

Note that there are three separate components here.

So, I have knowledge that this is a cat if: I first believe i’s a cat

And also that it is in fact a cat – that is, my belief corresponds to reality and is

therefore true. And finally, I can be said to have knowledge about this cat if my belief

is justified – meaning, I have some sort of legitimate evidence to support my belief.

Now, we’ve already defined truth and belief. Justification is simply evidence, or other

support, for your belief. If you remember back to episode 2, you’ll recall that premises

offer justification for conclusions. And justification can come in a variety of forms. Most often,

it comes about through testimony – just taking someone’s word for it. Not all testimony

is strong, or trustworthy, of course. But if it comes from someone who’s an expert

on the topic in question, you might consider the testimony to be reliable.

And the fact is, most of what you know about the world, you learned through testimony.

You took your teachers’ word for it when they were teaching you stuff, and the same

goes for every book you’ve ever read and every news report you’ve ever seen. They’re

all just forms of testimony, which you accepted as justification for your knowledge, and your beliefs.

But justification can come in other forms, too. Another common type is first person observation

– information you acquire through your senses.

If I believe that a cat is a cat, because I already have robust and well-informed beliefs

about cats, then, having had extensive experience with them in the past, I’m identifying the

cat as a cat through my direct contact with it

It looks, feels, acts like a cat. Ergo: cat!

But! Philosophy wouldn’t be any fun if the key to knowledge were that easy, right?

Until American philosopher Edmund Gettier came along in the 1960s, philosophers were

in pretty widespread agreement about the definition of knowledge -- that it’s justified true belief.

Because, you can believe any old thing, but in order to know something, it just makes

sense that you must also have evidence for your belief, and it must be true. In other

words, you can have a false belief, but you can’t have false knowledge. And if something

you thought you knew turns out not to be true, then the fact is, you never actually knew it, you just believed it.

And likewise, you might happen to hold a true belief, but if you don’t have any justification for it, if you

just accidentally happened to be right, which happens sometimes – that doesn’t count as knowledge, either.

Enter Edmund Gettier. Gettier wrote a short but fabulously influential paper that turned

the standard understanding of knowledge upside down.

He did this by proposing what came to be known as Gettier cases – situations in which one

can have justified true belief, but not knowledge.

Which brings us to this week’s Flash Philosophy! Let’s go to the Thought Bubble.

Here’s one of Gettier’s original cases. Smith and Jones have both applied for the same job.

The president of the company told Smith that Jones will get the job. This counts as evidence;

the president of the company would seem to be a reliable source of this information.

Meanwhile, Smith counts the coins in Jones’ pocket and sees that there are

ten coins in there. Smith then forms a belief, based on his first person observational evidence

of the coins, as well as the testimony of the company president.

He comes to believe that: The person who gets the job has 10 coins in his pocket.

But, it turns out, the testimony of the president was false, and it’s Smith, not Jones, who gets the job.

AND, it just so happens, unbeknownst to Smith, that he also has 10 coins in his own pocket.

So, Smith has a belief – that the person who gets the job has 10 coins in his pocket.

And that is justified – because he counted Jones’ coins, and the president told him

Jones was getting the job. And his belief also turns out to be true – the person who

got the job did have 10 coins in his pocket.

However, neither pieces of justification actually pointed Smith to the right answer. The president’s

testimony was wrong, and the 10 coins that he saw were in Jones’ pocket, not his own.

So it seems Smith simply lucked into being right.

Gettier argued that we now have a case of justified true belief that is not knowledge.

As he pointed out, you don’t KNOW something if you simply stumbled into the right answer.

Thanks Thought Bubble, the philosophical world was turned upside down by this idea, and philosophers

– loving a good counterexample – began generating their own Gettier cases.

American philosopher Roderick Chisholm proposed this one:

Looking across a field, you see an object that looks like a sheep, and you form the

belief that “there is a sheep in the field.”

It turns out that the object you see is actually a dog.

Yet, there is also a sheep, obscured from your vision by a hill.

So, you have a justified true belief, but the justification for your belief -- the object

that you saw – is not a sheep. You just lucked into being right.

Once you understand how it works, it’s pretty easy to generate Gettier cases of your own.

And many philosophers today think that Gettier successfully destroyed the “justified true belief” definition of knowledge.

But even though the 1960s might seem long ago to you, remember: philosophers are in

the business of having millennia-long debates about stuff. So it shouldn’t surprise you

that the philosophical debate about this is still a-raging.

But if knowledge is not justified true belief, then…whaaat is it?

Next time, we will look at one possible answer.

In the meantime, you learned about some of the key concepts we use when discussing belief

and knowledge. You learned what defines an assertion and a proposition, and that belief

is a kind of propositional attitude. We also learned about forms of justification and the

traditional definition of knowledge, which Edmund Gettier just totally messed with, using his Gettier cases.

And the cat did not pee on my desk! Because the cat was unable to spend any time at all

on my desk. So it turns out the assertion that I made was false.

But it is a true assertion that this episode was brought to you by Squarespace. Squarespace

helps to create websites, blogs or online stores for you and your ideas. Websites look

professionally designed regardless of skill level, no coding required. Try Squarespace

at squarespace {dot com} {forward slash} crash course for a special offer.

Crash Course Philosophy is produced in association with PBS Digital Studios. You can head over

to their channel to check out amazing shows like Game/Show, The Chatterbox, and Physics Girl

This episode of Crash Course was filmed in the Doctor Cheryl C. Kinney Crash Course Studio

with the help of these awesome people and our equally fantastic graphics team is Thought Cafe.