ےشروع الل ک پاک نام س ے ہا ر بان ن ہجو بڑا م ت رحم ی�ہ

۔واال ہے

ہہبسم الل ح حمن الر می�الر

Group # 9

Danish Raza 13170920-072Ali Asghar 14220920-017

Existential import

A statement has existential import when its truth depends on evidence for the existence of things in a certain category--in the case of categorical propositions, the existence of things in the categories signified by its subject and predicate terms.

Example: 1: All buttercups are blueBlue buttercups exist

2: Some dragons are fire-breathing fire-breathing dragons exist

Different forms of Existential Import

Formal & Material Import Bivalence Import Traditional Views The Golden Age of Logic Fred Sommer and Existential Import Material Implication

Formal & Material Import Formal The structure of arguments in order to see how

reasoning proceeds from premises to a conclusion.

Material It does not deal with the form or structure of

arguments, but rather with their content. While formal logic deals with how you get from one truth to another.

Example

All men are mortal Socrates is a man Therefore, Socrates is mortal

Bivelence Logic logic philosophy the semantic principle that

there are exactly two truth values, so that every meaningful statement is either true or false.

Example T & T =T F & T= F T & F= F F &F= T

Traditional Views Traditional logic involves mostly the study of the classical syllogism.

Example Murder is wrong. Some times murder is not wrong. Therefore murder is always wrong.

The Golden Age of Logic The golden age of logic occurred during the

19th century, when such giants as Boole, ideal precisely because there are none who fit the ideal,

Example “perfect men do not break the rules.” This does not imply that even if a man were to

refrain from breaking the rules, that perfect men actually exist.

It is ideal precisely for that

reason. Venn says, however, that

in popular usage we do not

“without warning” make predicates

of non-existence subjects.

Fred Sommers and Existential Import

Fred Sommers discussed P. F. Strawson’s

attempt to use “truth-value gaps” as a way of

interpreting such expressions as, (1) “the

present king of France is bald.” The “present

king of France” has no existence, so under

Russell’s view of existential import,

The proposition would be false merely

because its subject term was vacuous

Russell regarded the subject term as

entailing that there was a present king of

France and the proposition was false for

that reason.

Material implication

A conditional statement describes a relationship between the antecedent and the consequent. This relationship is called "material implication"

Denoted by: “=>” or

For Example If you study hard, then you will pass.

Antecedent Consequent

=> If p, then q.

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