I have three premises with me defined:
- $(B \land L) \implies A$
- $(A \land D) \implies \lnot H$
- $\lnot J \implies (D \land \lnot H)$
I need to prove the following conjecture with the help of the above premises:
$(B \land L) \implies J$ and $(A \land H) \implies J$
Please help me out.
$(B \land L) \implies J$ holds by 1).
To prove the second conjecture, suppose $A$ and $H$ hold. If $J$ does not hold, then by 3) $D$ and $\neg H$ hold, contradicting $H$. Hence $J$ holds. So $A \land H \implies J$.
After the edit: $(B \cap L) \implies J$ does not hold. If $B, L, A, D$ hold, but $J$ and $H$ do not, then 1), 2) and 3) are true, but $(B \cap L) \implies J$ is not.