An interpretation or valuation is a function that assigns a truth-value to every propositional symbol $P$, hence $v(P) \in \{ 0, 1 \}$.

  • If , then is true under the interpretation .
  • If , then is false under the interpretation . An interpretation is extended to all well-formed formula using truth-tables.

As oppossed to FC1, we include an extra column for for interpretation. For example, take , we generate the following truth table:

interpretation
FFF
FTF
TFF
TTT