Rule of Assumption/Boolean Interpretation

Definition
Let $\mathbf A$ be a statement form.

The boolean interpretations for $\mathbf A$ under the model $\mathcal M$ are:


 * $\left({\neg \mathbf A}\right)_\mathcal M = \begin{cases}

T & : \mathbf A_\mathcal M = T \\ F & : \mathbf A_\mathcal M = F \end{cases}$