Propositional Logic

Proposition - A declarative sentence that states a fact or statement that results in either True or False

Logic Operators & Compound Propositions

SymbolNameIntuition
¬\negnegationnot
$\wedgeconjunctionand
\veedisjunctionor
\toimplicationif ... then
    \iffequivalenceif and only if
\oplusexclusiveeither
\forallfor allall have to be true
\existsthere existsat least one

More Terminology

  • Conditional Statement (if, then)
    • pqp \to q: "pp implies qq, if pp then qq"
  • Converse:
    • qpq \to p
  • Contrapositive:
    • ¬q¬p\neg q \to \neg p
  • Inverse:
    • ¬p¬q\neg p \to \neg q
  • Biconditional
    • p    qp \iff q: "p if and only iff q"