Description: A deduction from a biconditional, similar to modus tollens. (Contributed by NM, 10-May-1994)
Ref | Expression | ||
---|---|---|---|
Hypotheses | mtbird.min | |
|
mtbird.maj | |
||
Assertion | mtbird | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | mtbird.min | |
|
2 | mtbird.maj | |
|
3 | 2 | biimpd | |
4 | 1 3 | mtod | |