Class and Int logical rules

&I A, B
A & B
&E A & B
A
A & B
B
∨I A
A ∨ B
B
A ∨ B
∨E A ∨ B, A ⊃ C, B ⊃ C
C
⊃I A*
.
.
B
A ⊃ B
⊃E A ⊃ B, A
B
TI T ⊥E ¬ A*
.
.
⊥
A
∀I x *
.
.
A(x)
∀x A(x)
∀E ∀x A(x)
A(t)
∃I A(t)
∃x A(x)
∃E ∃x A(x)
A(y)
=I t = t =E t = s, A(t)
A(t//s)
* marked formulae are assumptions of subproofs

Note that A ≡ B is a shortcut for (A ⊃ B) & (B ⊃ A), so we don't need rules for ≡. Also ¬ A is a shortcut for (A ⊃ ⊥). The rules are divided into direct (simple justification) and indirect (proof and subproof) rules. Apart from mentioned rules we need for reiteration rule. By changing mentioned ⊥E to the same-named following rule we will get intuitionistic system.
  A
A
⊥E ⊥
A

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