PHIL 101 Test 3

epistemology

study of knowledge

three types of knowledge

1. know-how
2. object knowledge
3. propositional knowledge
**if you have one you don't necessarily have all three

know-how knowledge

ex. I know how to play guitar

object knowledge

ex. I know John

propositional knowledge

ex. I know that 2 + 2 = 4

conditions for a good definition

1. necessary
2. sufficient

biconditional

X if and only if Y
(X c Y) ^ (Y c X)
*stands and falls together

TRUE OR FALSE: Plato says true belief is sufficient for knowledge

FALSE! Plato says true belief is NOT enough; we need to justify (justification = objective)

JTB Theory of Knowledge

Knowledge is justified true belief (JTB for short)

1) s must believe p
2) p must be true
3) s must be justified in believing p

Counterexamples to JTB

1. Edmund Gettier - we can have a justified belief and be wrong
2. Bertrand Russel - broken clock is right twice a day
3. Sober - odds say lottery ticket won't win

Does justification require infallible evidence?

Sober says no, evidence can justify belief even if truth is not guaranteed
says JTB isn't sufficient for knowledge

Skepticism argument

if S knows P, then S is not mistaken in belief
it's possible S is mistaken
therefore, S does not know P

Descartes Foundationalism

Knowledge must be built upon a foundation that is completely certain or "indubitable" (can't be doubted)

anti-Aristotelianism

- movement against Aristotle's teachings as they were supported by the church
- those against Aristotle's teachings could be labeled as a heretic

Euclid

Greek mathematician; considered to be the father of modern geometry

axiom - Descartes

foundational belief - self-evident and does NOT count as knowledge

Descartes task and goal

task - identify all foundational beliefs and if they can be doubted; if not, then yes its foundational
goal - refute skepticism

posterioiri propositions

known by expereince

Thesis of Incorrigibility of the Mental

Descartes: each of us has infallible access to our beliefs and desires (so we can't be wrong about them)
Freud and others dispute this (say people lie)

a priori propositions

prior to experience (reason alone)

can you doubt the phrase "I am thinking" or "I exist"

indubitable proposition
Descartes said no, believing/doubting makes it true

properties of "I think"

1. first person
2. involves psychological property (property of mind)

Cognito Ergo Sum

I think therefore I am

can you doubt "I saw Rob walking"

dubitability
yes - to make it better, say, "I seem to remember Rob walking"

1. foundational beliefs
2. superstructure beliefs

1. "I think" "I exist" - first person subjective belief/desire
2. outside world, objective

how do I get from foundational beliefs to superstructure beliefs

idealism, solipsism
Descartes's solution: show God exists and he doesn't deceive

Descartes proof God exists

p1. my idea of God is a perfect being (introspection, can't doubt)
p2. must be as much perfection in the cause as the effect
c. God exists

Cartesian Circle claim

Descartes's proof that God exists and is not a deceiver is circular

two causality principles

1. every event has a cause
2. cause must be at least as perfect as the effect

Descartes two kinds of perfection

1. objective: if we represent God, but our idea has a limit to perfection
2. formal: all mental content has the same amount of perfection

revised argument for Gods existence

p1. my idea of God is objectively perfect
p2. if idea is objectively perfect, then cause of it must be perfect being
c. God exists

two types of skepticism

1. Descartes - How your present mental state justify your beliefs about your physical environment
2. Hume - How predictions about the future are justified, given the past and present observations you have made about your physical environment

two kinds of arguments

1. GEN -
p1. all A's observed so far have been B
c. all A's are B's
2. PRED -
p1. all A's observed so far have been B
c. the next A I observe will be B

matters of fact

can be
1. observed (it's right there) or
2. unobserved (it will happen)

PUN

Humes principle of uniformity of nature:
the future will resemble the past

Yes or no: Can PUN be justified by an inductive argument?

no - according to Hume

three justification for PUN

1. induction
2. conclusion of a deductively valid argument
3. definitional truth
Hume says none of these can rationally justify PUN

Hume's solution to problem if induction

Instead of providing a justification of induction, Hume describes our use of inductive inferences

three requirements for PUN

1. something we believe
2. gives us definite advice about what we should infer from observations
3. to make inductive arguments, PUN us something we must believe, no matter what else we believe

Rules of inference provide __________ that allow us to draw conclusions

licenses

Strawson's response to Hume's reformed argument

analytic; denies that induction needs rational justification; it's true by definition - induction being rational doesn't imply reliable

Black's response to Hume's reformed argument

inductive; says inductive justification of induction isn't circular

circular argument

conclusion is also a premise - has to have exact same wording

inductive inference

p1. induction has been highly reliable
c. probably, induction will be reliable in the future

counterinductive

p1. counterinduction has been unreliable in the past
c. probably, counterinduction will be RELIABLE in the future

Bayesian Epistemology

formal way to define evidence, confirmation, and rational belief

confirmation theory

Attempted to analyze the acquisition of knowledge from experience - update with new evidence as you got it

3 axioms

non-negativity: Pr(x) greater than or equal to 0 for all subsets x
normalization: Pr(Ω) = 1
finite possibility: Pr( A or B) = Pr(A) + Pr(B) if A & B are mutually exclusive

conditional probabilities

if... then ...
standard definition: [Pr (a&b)] / Pr (b) = Pr (a|b) is probability of a given b

ex. probability of rolling a 6 is the die is guaranteed to be even
[Pr (6 | even) / Pr (even) = Pr (6)/Pr (even) = [1/6] / [3/6] = 2/6 = 33%

(A|B) is undefined if ...

1. Pr (B) = 0
2. A or B are undefined
3. events are measured sets

Hume's problem of induction

It suggests that we can't logically prove that the future will resemble the past, even though it seems intuitively reasonable.

Conditionalism

how we learn from experience - we should update how likely our hypothesis is with new evidence

find a way to calculate Pr(H|O) as a function of Pr(H)

Pr(H|O) = [Pr(H&O)] / Pr (O)

Reverend Thomas Bayes

Doctrine of Chances - probabilities evolve over time

Bayes Theorem

since Pr(A&B) = Pr(B&A), (A|B)(B) = (B|A)(A)

Confirmation

Observation O confirms hypothesis H if and only if
Pr(H|O) > P r(H)

Disconfirmation

Observation O disconfirms hypothesis H if and only if
Pr(H|O) < P r(H)

Independance

Observation O is evidentially irrelevant hypothesis H if and only if
Pr(H|O) = P r(H)

Bayesian Updating

1. determine probability of hypothesis and likelihood of evidence
2. determine probability to observe evidence independent of hypothesis
3. if evidence is observed, use theorem to calculate probability
repeat 1-3 for each piece of new evidence

Odds Formulation of Bayes's Theorem

[Pr(H1|O)] / [Pr(H2|O)] = [Pr(O|H1) Pr(H1)] / [Pr(O|H2) Pr(H2)]

base rate fallacy

The tendency to ignore information about general principles in favor of very specific but vivid information.

Principle of indifference

In the classical theory of probability, the principle that the various possible outcomes are equally probable.
an objection to Bayesianism

Dutch book theorem

A result in probability theory stating that inconsistent probabilities create profit opportunities.

ancient Greeks said three types of love

1. eros - sexual passion for person/object
2. agape - love doesn't respond to values - brotherly live independent of characteristics
3. philia - affectionate friendly feeling - responds to value, ex. love of country

love vs. like

love has depth: loving someone is identifying yourself with them

what is love (Aristotle)

it promotes self-knowledge, a kind of mirror

epistemology questions of love

what justifies loving and not loving?
what justifies loving one person and not others?
what justifies continuing to love someone?

problems with questions of love

if justification is based off reason, then anyone with the same traits we should love just as much.
loving someone in the past doesn't justify loving them in the future

Greeks base love on these two things

education and patience

Idealism of love

there is one perfect soulmate with perfect compatibility
criticism - illusion that we already know each other and shouldn't change

why will we marry the wrong person (Alain De Botton)

we don't associate love with being happy
we seek familiarity (childhood)

what's the solution

become at peace with being alone (heroic acceptance)

how to be better in relationships

start with what is wrong with each other, no idealism
no conflict-free love
don't be self-righteous

what is marriage in this article?

"gamble taken by two people who don't know themselves or each other, without thinking of the future"

why do people marry

to make nice feelings permanent

what does Button say "make or break" marriaige

the day-to-day things - who will take our trash