A [[Proof System]].
**Rules for the quantifiers**
- Universal elimination ($\forall \text{Elim}$):
- Existential introduction ($\exists \text{Intro}$):
- Universal introduction ($\forall \text{Intro}$):
- Existential elimination ($\exists \text{Elim}$):
Rules for $=$
- Identity Elimination ($=\text{Elim}$):
- Identity Introduction ($=\text{Intro}$):