Unit 1.B: Propositions and Truth Values

Proposition

• a complete statement that can be classified as true or false, an assertion or denial.

  • They cannot be questions, commands, or incomplete sentences

Truth Values

True or False

Negation

Another proposition that makes the opposite claim of the original (symbolized by ~, read as “not”); makes a true claim false and vice versa.

Conjunction (And Statement)

Given two propositions p and q, the statement “p and q”; it is true only if p and q are both true.

Disjunction (Or Statement)

Given two propositions p and q, the statement “p or q”; it is true unless p and q are both false.

Inclusive Or

• Means “either or both”

• In logic, assume “or” is inclusive unless told otherwise

Exclusive Or

Means “one or the other,” but not both