Being Logical 2

8/4/2019 Being Logical 2

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BEING LOGICAL:BEING LOGICAL:

The Basic Principles ofThe Basic Principles ofLogicLogic



Logic and language are connected!

Three basic components to human knowledge:

1. Objective fact – a cat

2. The idea of a cat

3. The word we apply to the idea, which allows us to

communicate it to others. In English, “cat.”

It all starts with the cat. If there were no real cats,

there would be no idea about them and there would

be no words for the idea.





The purpose of logic and critical thinking is to arrive

at truth.

Two kinds of truthOntological Truth – big word for a simple meaning.

Saying something is “ontologically true” just means it

exists. Example – this computer, classroom, that guy

over there.

Logical Truth – The truth of statements.

A statement is an expression in language that you

can say is either “true” or “false.”

TruthTruth



Respond to the following:

Payap has a beautiful campus. What is this?

Do you agree?

Why or why not?

In Class Reflection



A statement is an expression in language that you

can say is either “true” or “false.”

The Payap University campus is located in Chiang

Mai, Thailand.

The Payap University campus is a beautiful campus.

The second statement is an evaluative or “value”

statement. It is subjective opinion and should not be

treated as objective fact.

statementsstatements



A categorical statement tells us that something is

definitely the case

The purpose of an argument is to demonstrate – to

show that something is true

Argument is the activity of logic

An argument is only as good as its statements

The most effective argument is one whose

conclusion is a categorical statement

The Cat egor icalThe Cat egor ical

st at ementst at ement



The cat is in the house.

The cat may be in the house.

Categorical statements/arguments provide us with

certain knowledge.

It is important to back up categorical statements with

good evidence.

ExamplesExamples



What do think of the following statement: All

generalizations are bad.

All cats are mammals.

- A universal statement → uses “every,” “all,” or “no”

Most cats have claws.

-A particular statement → uses “some,” “most,” only

refers to part of a group

The problem with generalizing is that often people

use universal statements when they should use

particular statements

GeneralizingGeneralizing



1. The Principle of Identity

A thing is what it is.

Reality is made of separate individuals.

An apple is an apple. Not an orange or a banana.

The Fir The Fir st Principles of st Principles of

LogicLogic



2. The Principle of the Excluded Middle

There is no state between “being” and “non-being.”

There is no “becoming.” Becoming is a change is

something that already exists.

3. The Principle of sufficient Reason

There is an explanation for everything.

Nothing is the cause of itself.


LogicLogic



4. The Principle of Contradiction

It is impossible for something to be and not be at the

same time.

Example: I am in Thailand. I am in America.

Sometimes we believe contradictions without

knowing it → ignorance

Sometimes we lie to ourselves → rationalize

Sometimes we avoid the facts.


LogicLogic



Life is full of gray areas!

-But don't give up on reasoning

Gray relies on black and white

You could not be uncertain without having been

certain → certainty exists

There is an explanation for everything (eventually)-We seek causes because they help us understand

the world (and control it)

““But Aj., What about grayBut Aj., What about gray

areaareas?”s?”



Work backward from effects

Don't stop short → laziness or impatience

Example: A causes B which causes C

Looking for CausesLooking for Causes



Efficient Cause – “an agent whose activity bringssomething into existence or modifies its existence.”

-something that causes or changes something else

Final Cause – the purpose of the activityMaterial Cause – material out of which an object is

composed

Formal Cause – the “identifying nature” of a thing-How you describe it

Example: a garden

Not everything has all four causes

Types of CausesTypes of Causes

Documents

Being Logical 2