Categorical Propositions Chapter 5

Deductive Argument A deductive argument is one whose premises are claimed to provide conclusive grounds for the truth of its conclusion. Valid or Invalid

Deductive Logic Relationship b/w premises and conclusion. Techniques for appraisal of deductive arguments. Classical or Aristotelian Modern or Modern Symbolic

Class Collection of all objects that have some specified characteristic in common.

Categorical Propositions Such propositions affirm, or deny, that some class S is included in some other class P, in whole or in part. Relationships between classes are affirmed or denied by categorical propositions.

Types of Categorical Propositions Universal Affirmative Universal Negative Particular Affirmative Particular Negative

Types of Categorical Propositions All politicians are liars No politicians are liars Some politicians are liars Some politicians are not liars

Universal Affirmative A A universal affirmative proposition says that every member of the first class is also a member of the second class. All S is P A proposition

Universal Negative E Universal negative proposition says that the first class is wholly excluded from the second. No S is P E proposition

Particular Affirmative I At least one member of the class designated by the subject term S is also a member of the class designated by the predicate term P. Some S is P I proposition

Particular Negative O At least one member of the class designated by the subject term S is excluded from the whole of the class designated by the predicated term P. Some S is not P O proposition

Quality If the proposition affirms some class inclusion, whether complete or partial, its quality is affirmative. If the proposition denies class inclusion, whether complete or partial, its quality is negative.

Quantity If the proposition refers to all members of the class designated by its subject term, its quantity is universal.

Distribution A distributed term is a term of a categorical proposition that is used with reference to every member of a class. If the term is not being used to refer to each and every member of the class, it is said to be undistributed.