Rule of Addition/Proof Rule/Tableau Form
Proof Rule
Let $\phi$ and $\psi$ be two propositional formulas.
The Rule of Addition is invoked in a tableau proof for $\phi$ or $\psi$ in either of the two forms:
- Form 1
Let $\phi$ be a propositional formula in a tableau proof.
| Pool: | The pooled assumptions of $\phi$ | ||||||||
| Formula: | $\phi \lor \psi$ | ||||||||
| Description: | Rule of Addition | ||||||||
| Depends on: | The line containing $\phi$ | ||||||||
| Abbreviation: | $\operatorname {Add}_1$ or $\lor \II_1$ |
- Form 2
Let $\psi$ be a propositional formula in a tableau proof.
| Pool: | The pooled assumptions of $\psi$ | ||||||||
| Formula: | $\phi \lor \psi$ | ||||||||
| Description: | Rule of Addition | ||||||||
| Depends on: | The line containing $\psi$ | ||||||||
| Abbreviation: | $\operatorname {Add}_2$ or $\lor \II_2$ |