The tripartite view Flashcards
what is the tripartite definition of knowledge
true belief accompanied by a rational account
1. justification 2. truth 3. belief
necessary and sufficient conditions
JTB
- we argue that ‘justification, truth and belief’ are all necessary for knowledge
- and all together the three conditions for knowledge are sufficient for knowledge
defining ‘knowledge’ is to provide necessary and sufficient conditions.
show how truth is necessary for knowledge
JTB
If someone said, “I know that the moon is made of green cheese” you wouldn’t consider that knowledge because it isn’t true.
show how belief is necessary for knowledge
JTB
It just wouldn’t make sense, for example, to say “I know today is Monday but I don’t believe today is Monday.”
show how justification is necessary for knowledge
JTB
Suppose someone asks you if you know how many moons Pluto has. You have no interest in astronomy but just have a strong feeling about the number 5 because it’s your lucky number or whatever. You’d be right – Pluto does indeed have 5 moons – but it seems a bit of a stretch to say you knew Pluto has 5 moons. Your true belief “Pluto has 5 moons” is not properly justified and so would not count as knowledge.
what do Gettier’s scenarios aim to achive in relation to JTB
an individual has a justified true belief that is not knowledge. Both scenarios describe a belief that fails to count as knowledge because the justified belief is only true as a result of luck.
What is Gettier case 1
- Smith and Jones are interviewing for the same job
- Smith hears the interviewer say “I’m going to give Jones the job”
- Smith also sees Jones count 10 coins from his pocket
- Smith thus forms the belief that “the man who will get the job has 10 coins in his pocket”
- But Smith gets the job, not Jones
- Then Smith looks in his pocket and, by coincidence, he also has 10 coins in his pocket
does smith have a JTB in case 1
belief- ‘the man who will get the job has 10 coins in his pocket’
justified - he hears the boss say jones will get the job and he sees that jones has 10 coins in his pocket
true- the man who gets the job (Smith) does have 10 coins in his pocket
why would we say smith doesn’t have knowledge in gettier case 1
espite being a justified true belief, we do not want to say that Smith’s belief counts as knowledge because it’s just luck that led to him being correct.
what does gettier case 1 prove
shows that the tripartite definition of knowledge is not suffiecient: you can have JTB that is NOT knowledge
what does gettier case 2 rely on
on the logical principle of disjunction introduction
what is the disjunction introduction
that if you have a true statement and add ‘some other statement’, then the full statement is also true
e.g “London is the capital of England” is true. And so the statement “either London is the capital of England or the moon is made of green cheese” is also true, because London is the capital of England. Even though the second part (“the moon is made of green cheese”) is false, the overall statement is true because the or means only one part has to be true (in this case “London is the capital of England”).
explain gettier’s second case
- Smith has a justified belief that “Jones owns a Ford”
- So, using the principle of disjunctive introduction above, Smith can form the further justified belief that “Either Jones owns a Ford or Brown is in Barcelona”
- Smith thinks his belief that “Either Jones owns a Ford or Brown is in Barcelona” is true because the first condition is true (i.e. that Jones owns a Ford)
- But it turns out that Jones does not own a Ford
- However, by sheer coincidence, Brown is in Barcelona
does smith have JTB in gettiers second case
belief- either jones owns a ford or brown is in barcelona
truth - either Jones owns a Ford or Brown is in Barcelona” turns out to be true. But Smith thought it was true because of the first condition (Jones owns a Ford) whereas it turns out it is true because of the second condition (Brown is in Barcelona)
justified- The original belief “Jones owns a Ford” is justified, and so disjunction introduction means that the second belief “Either Jones owns a Ford or Brown is in Barcelona” is also justified.
what does gettier’s second case prove
despite being a justified true belief, it is wrong to say that Smith’s belief counts as knowledge, because it was just luck that led to him being correct.
This again shows that the tripartite definition of knowledge is not sufficient.
how do philosophers respond to the gettier cases to the tripartite definition
make new definitions
e.g 1. JTB+no false lemmas, reliablism, virtue epistemology, infallibilism,
what does no false lemmas say
It says that James has knowledge of P if:
- P is true
- James believes that P
- James’s belief is justified
- James did not infer that P from anything false
adds an extra condition to the tripartite definition. It says knowledge is justified true belief + that is not inferred from anything false (a false lemma).