Critical Thinking 02 Truth

A Standard of Critical Thinking

Truth

Review

Principle of Sufficient Principle of Sufficient Reason: for any claim, Reason: for any claim, give reason why it is give reason why it is true, or not.true, or not.

Principle of Charity: for Principle of Charity: for any claim, give it the any claim, give it the strongest possible strongest possible interpretation.interpretation.

Philosophy: the attempt to Philosophy: the attempt to answer, critically, the answer, critically, the epistemological, epistemological, metaphysical, and ethical metaphysical, and ethical questions.questions.

An Issue Question: is a An Issue Question: is a yes-or-no question, and is yes-or-no question, and is the way to formulate the way to formulate questions for the disputed questions for the disputed question method (question method (quaestioquaestio disputatadisputata).).

A virtue is an excellence, A virtue is an excellence, a mean between two a mean between two extremes called vices.extremes called vices.

the question

yes:

no:

Reasons supporting the yes answer or

refuting the no answer.

Reasons supporting the no answer or refuting the yes

answer.

Which side has the better

reasons?

The Disputed Question Method

Review

What is the difference

between the truth, an honest

mistake, and a lie?

Truth

Matters of Taste or Matters of Taste or OpinionOpinion

Matters of ConventionMatters of Convention

Matters of FactMatters of Fact

Matters of NecessityMatters of Necessity

Four Types of Truth

Truth





Four Types of Truth

The ocean is prettier than the desert &The desert is prettier than the woods.

Truth





Four Types of Truth

The desert is prettier than the woods &The woods are prettier than the ocean.

Truth





Four Types of Truth Can be indexed to a person, place, time or culture:

According to Alex pizza is better than pot stickers.

>

Does this exhaust all truths?

Truth





Four Types of Truth Consider someone who

honestly believes red

means go and green means stop. Is his

belief true, or an honest mistake?

Truth





Four Types of Truth

Steering wheels are on the left.

Truth





Four Types of Truth

Steering wheels are on the right.

Truth





Four Types of Truth Can be indexed to a convention, culture or society:

According to the music business, Tupac is gangsta while My Chemical Romance is emo.


Truth





Four Types of TruthConsider a

world without people or

conventions, would water

still boil at the temperature we call 212º Fahrenheit?

Truth





Four Types of Truth

The earth is 93 million miles from the sun.—Some think this fact is contingent

—

Truth





Four Types of Truth

Water boils at 212º fahrenheit.—Some think this fact is

contingent—it could have been otherwise

Truth





Four Types of TruthSuch truths as often expressed ceteris paribus:

The earth is about 93 million miles from the sun on average.Water boils at 212º fahrenheit at standard barometric pressure.


Truth





Four Types of Truth

Consider a world with different

natural laws, would

1 + 1 = 2?

Truth





Four Types of Truth∏∏ == 3.141592...3.141592...

11 ++ 11 22==

π needs to be exact for a circle to be round

simple arithmetic is the way things are

—Most think these facts are necessary—

they could not have been otherwise

Truth





Four Types of Truth

∏∏ == 3.141592...3.141592...

Truth

to pursue the truth of a claim

avoid matters of taste, fill in the indices, and spell out the ceteris paribus.

Truth is when a claim Truth is when a claim matches what is.matches what is.

Claims are candidates Claims are candidates for truths, such as for truths, such as beliefs stated in beliefs stated in language.language.

The jellyfish has tentacles.

The child looks at the jellyfish.

Drinking milk is healthy.

Same-sex schools are optimal.

Eleven is a prime number.

Jacqui thinks black is more alluring than pink.

The music is loud.Jupiter is bigger than

Mars.

The Constitution of the United States was adopted on September 17, 1787

Romeo and Juliette is a tragedy.

New York is the largest city in the US.

Hockey is better than basketball.

The jellyfish has tentacles.

Why is this true?

Truth

Intensions— the concept that meanings are things with

properties and in relations

Meaning

The jellyfish

Because the thing designated by the

subject has the property expressed by

the predicate.

has tentacles.

How a claim matches what is.

Truth

yes:

no:




answer.


reasons?


Does the thing designated by the subject have the property expressed by the predicate?

Applied to Truth

to evaluate the truth of a claim

determine whether the thing designated by the subject has the property expressed by the predicate

The child looks at the jellyfish.

Why is this true?

Truth

The child

The things designated by the nouns stand in the relation expressed

by the predicate.

looks at

the jellyfish.

TruthHow a claim matches

what is.

yes:

no:




answer.


reasons?

Do the things designated by the nouns stand in the relation expressed by the verb.

Applied to Truth



determine whether the things designated by the nouns stand in the relation expressed by the verb.

When a claim matches what is: two forms

subject–Predicate Form subject–Verb–object Form

<<thing> property><<thing> property>

designates/expressesdesignates/expresses

((subject) Predicate)((subject) Predicate)

<<thing> relation<thing>><<thing> relation<thing>>

designates/expresses/designates/expresses/designatesdesignates

Truth

((subject) Verb(object))((subject) Verb(object))

TruthWhen a claim matches what is: subject/Predicate

form

The Claim What is: reality

The sunThe sun’’s gravity well bends light.s gravity well bends light.

<the sun<the sun’’s s gravity well>gravity well>

<<bending bending lightlight>>



((The sun’s gravity well) bends light.)


When a claim matches what is: subject/Verb/object form

The Claim What is: reality

The remora is on the shark.The remora is on the shark.

<remora><remora>

<<sharkshark>>

<<being being onon>> {

Truth



((The remora) is on (the shark)).((The remora) is on (the shark)).((subject) Verb(object))((subject) Verb(object))






((subject) Verb(object))((subject) Verb(object))

What is: things with properties and in relations

Meanings as intensions

Meaning

Extension— the concept that meanings are sets and their

members

Meaning

Meanings

MeaningMeanings minus things: concepts (or properties and

relations)

Thing

Concept

+hors

e

Seabiscuit

animal

Equidae

mammal

land animal

fast things

four legged things

_____is four legged.

_____is an animal.

_____is a horse.

_____is faster than_____.

_____is fast.

_____is an Equidae.

_____is bigger than_____.

Concepts

General and Specific

Red is a color.Red is a color.

A color is a wavelength of light.A color is a wavelength of light.

The cherries are red.The cherries are red.

A wavelength of light A wavelength of light is an electromagnetic phenomenon.is an electromagnetic phenomenon.

Concepts






Red as a concept.

Red as a thing.

Concepts






Color as a concept.

Color as a thing.

Concepts

Linking the General to the Specific





more

gen

era

lm

ore

gen

era

l

more

specifi

cm

ore

specifi

c

more

ab

stra

ct

more

ab

stra

ct

more

con

cre

tem

ore

con

cre

te

Concepts

Have Extensions

A

BC

D

E

F G

H

I

J

K

LM

NO

PQ

R

S

TU

V

W

X

YY Z

being a vowel

Properties as

Concepts

Concepts

Have Extensions

being divisible by two without a remainder

22

9

11

32 2

7

21

13

66

3

14

144 57

7

Relations as

Concepts


determine whether the things designated by the nouns are in the extension of the verb.

yes:

no:




answer.


reasons?


Are the things designated by the nouns are in the extension of the verb?

45

Definitions

Ambiguity: The Problem of Multiple Meanings

Names can be ambiguous:

Mary

Jupiter

Definitions

Ambiguity: The Problem of Multiple Meanings

Other terms can be ambiguous:

green

fire

Ambiguous applies to Ambiguous applies to terms with more than terms with more than one meaning.one meaning.

Definitions

Vagueness: the Problem of Unclear Extensions

Many terms can be vague:

bald – how many hairs before you stop being bald?

pile – how many make a pile?

A

BC

D

E

F G

H

I

J

K

LM

NO

PQ

R

S

TU

V

W

X

YY Z

being a vowel

is y in the extension of being a

vowel?

Definitions

Vagueness: the Problem of Unclear Extensions

Vague applies to terms Vague applies to terms with unclear extensions.with unclear extensions.

Definitions

Ambiguity and Vagueness

Some Terms Can Be Both Some Terms Can Be Both Ambiguous and Vague—Ambiguous and Vague—Try to come up with some:Try to come up with some:

to define a term

give it one clear meaning

Definitions

Claims with terms as things

Definitions

Claims with terms as things

SubjectSubject PredicatePredicate

‘claim’ means an assertion open to challenge

term meaning

<Thing> <Property>

yes:

no:




answer.


reasons?


Do the things in the extension of the term being defined have the property expressed by the meaning?

Definitions

Stipulating definitions

Make up your own terms Make up your own terms that you might characterize that you might characterize as as words that arenwords that aren’’t in the t in the dictionary but should bedictionary but should be..

Definitions


Sniglets*Words that don't appear in the dictionary, but should.

Aeroma (ayr oh' ma) - n. The odor emanating from an exercise room after an aerobics workout.

Aeropalmics (ayr o palm' iks) - n. The study of wind resistance conducted by holding a cupped hand out the car window.

Anaception (an a sep' shun) - n. The body's ability to actually affect television reception by moving about the room.

Animalanche: When you kick your stuffed animals in your sleep and they fall all over you or the floor. (from Kaffit, age 9)

Aquadextrous - adj. Possessing the ability to turn the bathtub faucet on and off with your toes.

Arachnidiot (ar ak ni' di ot) - n. A person, who, having wandered into an "invisible" spider web, begins gyrating and flailing about wildly.

Backspackle (bak' spak uhl) - n. Markings on the back of one's shirt from riding a fenderless bicycle.

Baldage (bald' aj) - n. The accumulation of hair in the drain after showering.

Bevemeter - The distance a coaster will stick to the bottom of a wet glass before falling to the table.

Bimp (bimp) - n. A blurry or "double-edged" felt-tip marker

Bixplex (biks' pleks) - n. Psychological block in which a person cannot choose which color of disposable lighter to purchase.

http://bertc.com/subfour/truth/sniglets.htm

Definitions


Sniglets show that we may prescribe or stipulate a definition for how a term ought to be used.

The examples from the dictionary show that we may describe or designate a definition for how a term is actually used.

In this class we will prescribe or stipulate technical definitions for how terms ought to be used.

Normative definitions Normative definitions which prescribe or which prescribe or stipulate how a term stipulate how a term ought to be used.ought to be used.

Normative claims which Normative claims which prescribe or stipulate prescribe or stipulate how things ought to be.how things ought to be.

Descriptive definitions Descriptive definitions which describe or which describe or designate how a term is designate how a term is actually used.actually used.

Descriptive claims which Descriptive claims which describe or designate describe or designate how things actually are.how things actually are.

Law of Assumption—Law of Assumption—assume anything at any assume anything at any time.time.


Sniglets are an example of applying this law.


Thought experiments are based on assumptions.


Critical Thinking has techniques to reject faulty assumptions.

define key terms

key terms are terms needed for the claim to be evaluated as true or false,

they are terms whose properties or relations need

to be specified or whose extensions need to be

clarified.

define technical terms

technical terms are terms needed for critical thinking, such as truth, charity, and

reason.

The Standard of Truth—The Standard of Truth—accept only those claims accept only those claims and definitions that have and definitions that have the best reasons for being the best reasons for being true. true.

ConsistencyConsistency

Assignment

How do you define contradictions?

Read the cases and list the contradictions you

find.

How do you tell when a conjunction is false?

Critical Thinking 02 Truth

Education

Transcript of Critical Thinking 02 Truth