嗨，我在解决Fitch Style Proof时遇到了麻烦，希望有人能帮助我。
前提:
A ^ (B v C)
B => D
C => E
目标:
~E => D
最佳答案
(1) A /\ (B \/ C) premise
(2) B -> D premise
(3) C -> E premise
.--------------------------------------------.
(4) | ~E assumption |
(5) | B \/ C /\ elimination of 1 |
| .--------------------------------------. |
(6) | | B assumption | |
(7) | | D -> elimination 2 | |
| '--------------------------------------' |
| .--------------------------------------. |
(8) | | C assumption | |
(9) | | E -> elimination 3 | |
(10) | | cont contradiction | |
(11) | | D ! elimination 10 | |
| '--------------------------------------' |
(12) | D \/ elimination 5, 6-7, 8-11 |
'--------------------------------------------'
(13) ~E -> D -> introduction 4-12