1.philosophy：the pursuit of wisdom in everything, discern any false beliefs

It’s not about questions that can’t be answered; most modern subjects are developed from philosophy ideas by philosophers;

it’s not about relative answers; answers are better by its coherent logic ：nazis, African girls，no matter how many people believe

so we cant tolerate all differences, unless the differences are about unproven assumptions

myth：everyone has a right to opinion

actually it should be informed by facts and baded in reasoning, which you should find

should not protect others ignorance，if you want wisdom and truth

the unexamined life is not worth living. links to our humanity. Intrinsically good

sometimes people with the truth might be ignored or hurt：socrates

should be open to the possibility of ignorance before you are wise, which takes courage

philosophy underpins the operation of the society, ought to understand its vital questions

2 why reason

give reasons to what you believe

Bias: most of us tend to rationalise what we want to believe and like what we want to see, even unwittingly—part of humanity

confirmation bias: interpret info to confirm our assumptions

lack of evidence to prove it right doesn’t mean that it is false

Russell: but lack of evidence in existence tends to prove nonexistence. the burden is on believer

Supernatural phenomenon: people tend to conclude unknown scenes to it

Fallacy in logic: begging the question: drawing conclusions from assumptions

changing the meaning of the arguments

Sometimes falls to fallacy because too much at stake or no time to examine

system 1 and 2

to prove yourself right, try to prove yourself wrong, and invite others, if you can’t, probably right; or admit that you are wrong

3.how to reason

Aristotle：3 laws of thought

A. Noncontradiction: nothing is both true or false

B. Excluded middle: either true or false

c. Identity: everything is identical to itself

Deduction - categorical: ~universal to particular

inductive: ~ particular to universal

statement: about facts, true or false

arguments: about reason, valid or invalid

If statements of premises are true, and arguments are valid, then the conclusions are true

if p then q；not q, then not q

When arguments are important, the truth of premises is almost always debatable

so deductive arguments are hard to be sound

Inductive: not about guaranteeing the conclusion, but more useful and powerful:

if premises provide good support, then the argument is strong- in degree

eg no scientific arguments are 100% valid, but if the inductive arguments are reasonably strong, then no one can doubt them

Usually assumes the future will resemble the past

3 ways of induction:

A.enumerative induction: induct from opinion polls ~fallacy: people care enough to weigh in

leading questions are biased

B.arguments from analogy: legal cases- precedents

C.Abduction: inference to the best explanation~

most reliable guide to truth

4.how to find the best explanation

That’s how most scientific findings are made:

accept a new theory if it’s a better explanation for the known fact

Can often be at odds with common sense

confirmation bias: the expected might not be the truth

senses or memories not reliable - bad events more memorable ; witness not always trusted

Counter: double blind test-both the patients and scientists don’t know who get the drug- placebo ; and replication - ensure no errors

5 criteria of abduction:

Compare the available assumptions and get the best one based on the above criteria

A.testability: able to test the assumptions

to be useful: must predict sth unknown

Myths are often untestable: The earth is flat-the pictures are fake - almost impossible to disprove

B. Fruitfulness

get predictions right - usually test them in certain conditions

C.scope

explanatory power: how much phenomena it explains

It should not raise more questions than it answers - not broaden our knowledge

D. Simple

it doesn’t invoke more assumptions and entities than necessary, especially the invented ones

All things equal, the simplest explanation is the best

E. conservatism

Coheres the known

5. What is the truth

the nature of truth

Knowledge:sth you know and believe, and true, justified, and based on evidence

Truth:

3 theories:

A.pragmatism:how the world will be different if the belief is true

usually clarifies the meaning to draw conclusions

Connects the concept to the world: hardness of sth - scratched by other objects exist in the world

Can be tested in experiments- not necessarily true: newton’s theory on planetary motions

B.coherence:

C.correspondence:

Pierce: truth is the ultimate result of scientific research

truth in morality or aesthetics:

But clearly false beliefs can do the same - Russell

Coherence theory: truth must be entailed by true beliefs

two ways of instructions:

A. Foundationalism

B. Web of beliefs: all truths are connected to each other in some way

if not consistent with the other views in the web, then untrue

Opposition: the web of beliefs might be wrong: Christ vs islam

even though people try their best to learn, their beliefs might not be true

C. Correspondence theory: truth accurately describes and corresponds to the world

happiness and good

hedonism

utilitarianism

high and low form of pleasure

reason and good

categorical imperative is broader， depends on the world you want to live in, or whether it can be universalised-talent development

Respect their humanity

be a good person

two pre-requisites：

Virtue and practical wisdom

Aristotle: fulfil human’s function-to reason

plato：be good is the only way to have a happiest and worthwhile life, even perceived as hateful (Socrates)

The composition of human-republic

To solve the problem of overreach: noble lie

—god has decided what class and qualities a person is —to stabilise the society

One’s appetite trumps others’

Socrates Freedom: acts according to one’s established law, not to every appetite that comes up, eventually one appetite rules all

Virtuous person- most fulfilling life, well-being :

wise- reason rules

courageous- motivated drive

tempered- controlled appetite

Limitation: noble lie, limited freedom

Although most ethical theories contain flaws,

we can treat them as criteria, and see how aligned an action is with them

five theories/criteria:

a. hedonism -happier life, worthwhile, sustained pleasure

b Kantian justice - respect rights and equality; can it be utilised? Person not merely as a mean but an end

c utilitarianism : greatest happiness for the greatest number

d virtuousness: what a moral exemplar do, whether it is consistent with a well-being soul

e feminist carefulness: care for others, justified preference for loved ones

The legitimacy of the government

anarchism

the theory that autonomy leads to true morality - no government

human society starts as an anarchist，but eventually people learn to cooperate and government- social contract come to existence

The justification of a government：

people agree on giving up some rights in exchange for the benefits of the government

survival : at the state of nature (killing, theft, raping)

to avoid the horror of nature

john Locke :sovereignty can do wrong when it violates(without consent(individual or majority ) or fail to protect citizens’ rights of life, liberty and property

Rousseau: to guarantee one’s freedom (by his standards) and serve the common good( even forced to give up all their rights )-socialism/communism

How big should a government be?

Economics

adam smith: apart from the invisible hand theory, he agrees that the government should provide services in certain industries, including utilities, infrastructure, education ; suggests avoiding monopolies

marx:

Against the suppression of workers and suggest only the capitalists own liberty

not liberty for all; wealth concentrated in the capitalists

Working class will revolt, take over the government, production, infrastructure and all industries. and make decisions directly, thus no need for officials

no more exploitation, abuse, alienation and profit equally shared

achieve abundance of material

Limitations:

A.The value of goods is much more than the cost of labour

B. Capitalists deserve compensation

C. Communism doesn’t yet happen in developed countries

D. Capitalism can repair itself: higher wages, more vacations