Mouth and stomach

Truth & ConsistencyStandards for Critical Thinking

Truth

Matters of Taste or Opinion

Matters of Convention

Matters of Fact

Matters of Necessity

Four Types of Truth

Does this exhaust all truths?

What is the difference between

the truth, an honest mistake,

and a lie?

Truth



Matters of Fact


Four Types of Truth

Truth



Matters of Fact


Four Types of Truth

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

Truth



Matters of Fact


Four Types of Truth

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

Truth



Matters of Fact


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

• According to Alex pizza is better than pot stickers.

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Truth



Matters of Fact


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



Matters of Fact


Four Types of Truth

Steering wheels are on the left.

Truth



Matters of Fact


Four Types of Truth

Steering wheels are on the right.

Truth



Matters of Fact


Four Types of Truth

Women wear skirts.

Truth



Matters of Fact


Four Types of Truth

Men wear kilts.

Truth



Matters of Fact


Four Types of Truth

Can be indexed to a convention, culture or society:

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


Truth



Matters of Fact


Four Types of Truth


Consider a world without

people or conventions,

would water still boil at 212º Fahrenheit,

ceteris paribus?

Truth



Matters of Fact


Four Types of Truth

The earth is 93 million miles from the sun.

Truth



Matters of Fact


Four Types of Truth

Water boils at 212º fahrenheit.

Truth



Matters of Fact


Four Types of Truth

Such 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



Matters of Fact


Four Types of Truth


Consider a cosmos without

earth, would Jupiter still be

larger than Mars, ceteris

paribus?

Truth



Matters of Fact


Four Types of Truth

1 + 1 2=

Truth



Matters of Fact


Four Types of Truth

∏ = 3.141592...

Truth



Matters of Fact


Four Types of Truth

∏ = 3.141592...

What is Truth?

The puppy is on the rug.

When a claim matches what is

The Claim What is: reality

Truth

((The puppy) is on the rug.)



((Subject) predicate)

Truth





((Designates) expresses)

Truth






<<Thing> property>

Truth






<<Thing> property>

Truth

The puppy is on the rug.



((The puppy) is on (the rug.))

<<Thing> relation<thing>>

((Subject) verb (Object))

<<puppy> being on<the rug>>

TruthWhen a claim matches what is


((The fire) is out.)((Subject) predicate)

<<Thing> property><<fire> being extinguished>≠

Not true False



((Photosynthesis) is a process by which light energy is converted into

chemical energy.)

<< Photosynthesis > being a process by which light energy is converted

into chemical energy >

=


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.

ConsistencyA Truth of Necessity in Logic

The Principle of Noncontradiction — No thing can, at the same time and in the same manner, both have and not

have the same property.

Let’s define ‘this square’ as the thing depicted below at x-position 303 px and y-position 318 px and of the dimensions 242 px by 242 px.

this square


Next let’s define ‘white’ as the color depicted below of the RGB values Red = 255, Green = 254, Blue = 235.

white


Now pay attention to your mental processes as we make the following claim:


Now pay attention to your mental processes as we make the following claim:

>>This square is white and this square is not white.<<


What was your reaction?


What was your reaction?


No thing can, at the same time and in the same manner, both have and not have the same property.

General:

No claim, adequately defined, can be both true and not true.

Special:


The Principle of Noncontradiction

p and not p

The Standard Form of a Contradiction:



Eleven is a prime number andeleven is not a prime number.

Jacqui thinks black is more alluring than pink andshe doesn’t.

The music is loud and the music is quiet.*

Jupiter is bigger than Mars and it is not bigger than Mars.

The Constitution of the United States was adopted on September 17, 1787 and The Constitution of the United States was adopted on July 4, 1776.*

Romeo and Juliette is a tragedy and it is not a tragedy.*New York is and isn’t the largest city in the US.*

Hockey is better than basketball but it is not better than basketball.*

The Standard Form of a Contradiction: p and not p



From Plato’s Republic

Plato on ContradictionSocrates said: It is obvious that the same thing will never do or suffer opposites with respect to the same part and in relation to the same thing at the same time. So if ever we find such contradictions we shall know that it was not the same thing but many.Socrates: For example, can the same thing be at rest and in motion in the same respect at the same time? Glaucon: Impossible. Socrates: Still, let's have a still more precise agreement so that we won't have any grounds for dispute as we proceed. Imagine the case of a man who is standing and also moving his hands and his head, and suppose a person to say that one and the same person is in motion and at rest at the same moment — we would respond that one part of him is in motion while another is at rest. Glaucon: Very true. Socrates: And suppose someone says that tops as wholes stand still and move at the same time — we wouldn't accept it because it's not with respect to the same part being at rest and in motion. Instead we'd but reply that it has an axis and a circumference and moves with respect to the circumference, as it spins, but with respect to the axis it is standing still.Glaucon: That's right. Socrates: Then such objections won't confuse us into holding that the same thing at the same time, in the same part or relation, can act or be acted upon in contrary ways. Glaucon: Certainly not. Socrates: Yet, instead of examining every objection and proving them untrue one by one, let us assume that no objects hold. But if this assumption is wrong, then none of our conclusions would hold. Glaucon: Yes.

The Principle of [Non]contradiction

Based on an excerpt from Plato’s The Republic

The Principle

How does Socrates intend to use this principle?

Socrates give the example of tops moving (spinning) and not moving (being stationary) at the same time—how does he show this is not a counter example to the Principle?

What is the main issue question?

From Plato’s Republic

Plato on Contradiction

Socrates: Just as the hands of the archer can't push and pull the bow at the same time — one hand pushes and the other pulls. Glaucon: Exactly. Socrates: Can it be that someone is thirsty and yet unwilling to drink? Glaucon: It happens all the time. Socrates: Would you say that part of the soul bidding them to drink, while another part masters the desire to drink by denying the unhealthy drink? Glaucon: Fair enough. Socrates: And such denial comes from the calculations of reason while the attraction proceeds from desire? Glaucon: Clearly. Socrates: So can we assume that they are two parts and different from each other — naming that in the soul whereby it reckons and reasons the rational and the other which lusts, hungers, thirsts, and feels desires the appetitive?

My Cousin VinnyWhat contradiction does Socrates reveal? List the contradiction in standard form (p and NOT p).

How is the contradiction related to the issue question?

Which side of each contradiction does Socrates take? What reasons could he give to show that the side he takes is true?

What about the other side of the contradiction? What reasons could you give to show that the side is true?

The Tripartite Soul

Assignment: Write a brief paper (1,000 words) answering what you take the MAIN ISSUE QUESTION to be in the reading, explaining how Socrates uses the principle of [non]contradiction to refute opposing claims. Be specific as to the claims being contradicted and the claims and arguments being rejected. Evaluate the Socrates' arguments—do they work? List your reasons why they do, or don’t. DUE IN 2 WEEKS.

Spiritual

Mouth and stomach