Natural Deduction Proof Checker
Sentential Logic
Problem Gen 1 →
Problem Gen 2 →
New Proof
~
·
∨
⊃
≡
(
)
Premises
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Conclusion
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Tip:
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<->
for ≡. Atomic sentences must be
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A ⊃ (B · C)
, not
A ⊃ B · C
.
New Proof
✓ Proof complete!
Line
Formula
Justification
Status
~
·
∨
⊃
≡
(
)
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&
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<->
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Formula for the next proof line
Rule
— select —
MP — Modus Ponens
MT — Modus Tollens
HS — Hypothetical Syllogism
DS — Disjunctive Syllogism
Simp — Simplification
Conj — Conjunction
Add — Addition
CD — Constructive Dilemma
DM — De Morgan
Com — Commutation
Assoc — Association
Dist — Distribution
DN — Double Negation
Trans — Transposition
Impl — Material Implication
Equiv — Material Equivalence
Exp — Exportation
Taut — Tautology
Lines
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