Proposition

provides reason, explanation to support a judgment made expresses an idea, explanation feeling or emotion. can be analyzed as either true or false

Argument are expressed through propositions can be either be valid or invalid

Elements of a Proposition

Subject term

the point under discussion the central focus or the main idea or the content in a proposition

Predicate term tells or describes something about the main idea (or the subject term) in a proposition

Copula

the connector b/w the subject & the predicate term; generally using the verb “to be”

4 Standard forms of C.P.

All government officials are natural-born citizens No involuntary act is a conscious act Several movie directors are passionate Not all commentators are objective

Quantity or Extension of the Proposition

The quantity of the proposition can be determined by checking the quantifiers used in each proposition

Universal if it implies each & every member of the class or if it signifies general expression & ideas common quantifiers are “all, every, no, no one, nobody, nothing, none, whoever, whenever, whichever, whomever, whatever, whenever”

Singular

if it refers to something definite or refers to only one.

Nouns, personal pronouns, collective nouns are example of singular quantifier

Particular if it pertains to a part of a whole or less than the whole, or something definite

indefinite pronouns are most commonly used particular quantifiers like “many, several. Most, few, almost all, not all, some, part, etc.

Quality of the Proposition

The quality of proposition is determined by the quality of the copula

Affirmative

whenever the predicate term accepts something of the subject term

Negative

whenever the predicate term negates or denies something of the subject term

Symbols of Proposition

A – Affirmative UniversalE – Negative UniversalI – Affirmative ParticularO – Negative Particular

Quantity or Extension of the Predicate

Is entirely different from the quantity of the proposition to determined the quantity of the predicate, the quality of the proposition, whether affirmative or affirmative is the point of reference

Particular if the quality of the proposition is affirmative, the quantity of the predicate is automatically particular

if the quality of the proposition is negative, the quantity of the predicate is automatically universal

Universal

This modern technology is the solution to our problem

Most ideas were not expressed

Subject term Predicate term

Quantity of proposition

Quality of the Prop.

Symbol Quantity of the predicate

Government officials

Natural-born citizens

Universal Affirmative A Particular

Involuntary act Conscious act

Universal Negative E Universal

Movie directors Passionate Particular Affirmative I Particular

Commentators Objective Particular Negative O Universal

All government officials are natural-born citizens No involuntary act is a conscious act Several movie directors are passionate Not all commentators are objective

a form of immediate inference an oppositional relation of propositions concern on establishing the logical relationships of propositions

A E

I O

CONTRARY

SUB-CONTRARY

SUB-ALTERN SUB-ALTERN

Randy was telling Miguel: Jun was wounded when Joey’s car bumped into his car. What a pity! “Later on, Franz was heard telling Miguel the same incident: Have you heard? Joey was wounded when Jun’s car bumped into his car

Jun was wounded Jun was not wounded

Contrary Proposition

Joey was not wounded Joey was wounded

Four Oppositional Relations

Contrary Propositions have same quantity but different quality If one proposition is affirmative the other one is negative having the symbols A-E or E-A

Rule for contrary proposition

contrary propositions cannot be true simultaneously but possible that both they may be false

Contrary Propositions

Everyone is giving pressure to the President No one is giving pressure to the president to resign

Contrary Propositions

A student asked his professor. Did we all pass in the test given yesterday?” The professor answered, “No” The student remarked, “Oh my God, nobody passed! It sure was a difficult test, whew!”

Every Filipino is pro-government None of the Filipinos are pro-government

Sub-Contrary Propositions

The quality differs- one is affirmative, the other is negative could be particular-affirmative or particular negative I-O or O-I

Rule sub-contrary proposition contrary propositions may be true simultaneously but impossible to be both be false at the same time

Many singers are brilliant composer; Not all singers are brilliant composer

Sub-Contrary Propositions

Not many Senators are for charter change; All of them are for charter change

Contradictory Propositions

have different quantity and different quality could be A-O, O-A, E-I, I-E

Rule contradictory propositions impossible for both propositions to be true or false simultaneously

If it is true that all contracts were signed by the engineers; it is absurd to say that not all the contracts were signed by the engineers

Some efforts were taken to improve tax efficiencies; No effort were taken to improve tax collection efficiencies

Many Filipino-American businesswomen are not member of that international organization; All Filipino-American businesswomen are members of that international organization

Sub-altern Propositions

have the same quality but different quantity, propositions can either be affirmative or negative; universal in quantity while the other is particular could be A-I, I-A, E-O, O-E

Rule sub-contrary prosition

The particular is true, if the universal is true; The particular is doubtful, if the universal is false; The universal is doubtful, if the particular is true The universal is false, if the particular is false

All human actions are either morally good or morally evil; Most human actions are either morally good or morally evil

No individual perspective is free of any prejudicial assumptions; Not every individual perspective is free of any prejudicial assumptions

Many Filipino-American businesswomen are not member of that international organization; All Filipino-American businesswomen are not members of that international organization

Syllogism

a form of deductive reasoning where conclusion must logically follow from the premises

basically composed of two premises and a conclusion

premises serve as arguments, reasons or explanations that support conclusion they are propositions that express complete thought

Terms in the Syllogism an expressed idea but does not express a complete thought

there are three terms in the syllogism;

Minor Term – the subject of the conclusion - represented by symbol S

Major Term – the predicate of the conclusion - represented by symbol P

Middle Term – the common ground by which the major & minor term are analyzed

- represented by symbol M

No part of the culture of violence is solved by culture of impunityAll killings of activist lawyers are part of the culture of violenceAll killings of activist lawyers are not solved by the culture of impunity

PS

M

Middle Term – should never appear in the conclusion otherwise there is no argument at all- otherwise it will be a

circular reasoning

Mood

Each syllogism has a mood that refers to the symbols of each propositionThe quality & quantity of the proposition are the bases of the symbols

No part of the culture of violence is solved by culture of impunityAll killings of activist lawyers are part of the culture of violenceAll killings of activist lawyers are not solved by the culture of impunity

EA

E

The mood of the syllogism is EAE

Figure

The position signifies whether it is taken as either the subject or predicate in the premises

The figure refers to the position of the middle term in the premises

There are 4 figures that a syllogism may have

Figure 1 (the middle term is the subject in the major premise

and it is the predicate in minor premise)No M is PAll S is MNo S is P

No friend of mine is a Japanese.But, Sandra is a friend of mine.Hence, Sandra is not a Japanese.Figure 2 ( middle term is the predicate in both premise)

All P is M Not all S is MNot all S is P

All computer machine are man-made.A molecule is not man-made.Ergo, a molecule is not a computer machine.

The mood of the syllogism is EAE

The mood of the syllogism is AOO

Figure 3 (middle term is the subject of both premises)

Some M is PEvery M is SSome S is P

Several news items are objects of criticism.But all news items are those which give information.So, those which give information are objects of criticism.The mood of the syllogism is IAI

Figure 4 (middle term is the predicate of the major premise & the subject in the minor premises)

All P is M No M is SNo S is P

“Mga Kababayan Ko” is a rap music.But rap music is not a hit of the 70s.Thus, the hit of the 70s is not “Mga Kababayan Ko.”

mood is AEE