Description: Thus, there is at most one isomorphism between any two set-like well-ordered classes. Class version of wemoiso . (Contributed by Mario Carneiro, 25-Jun-2015)
Ref | Expression | ||
---|---|---|---|
Assertion | weisoeq | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | id | |
|
2 | isocnv | |
|
3 | isotr | |
|
4 | 1 2 3 | syl2anr | |
5 | weniso | |
|
6 | 5 | 3expa | |
7 | 4 6 | sylan2 | |
8 | simprl | |
|
9 | isof1o | |
|
10 | f1of1 | |
|
11 | 8 9 10 | 3syl | |
12 | simprr | |
|
13 | isof1o | |
|
14 | f1of1 | |
|
15 | 12 13 14 | 3syl | |
16 | f1eqcocnv | |
|
17 | 11 15 16 | syl2anc | |
18 | 7 17 | mpbird | |