Description: A version of Russell's paradox which is proven using proper substitution. (Contributed by Andrew Salmon, 18-Jun-2011) (New usage is discouraged.) (Proof modification is discouraged.)
Ref | Expression | ||
---|---|---|---|
Assertion | rusbcALT | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | pm5.19 | |
|
2 | sbcnel12g | |
|
3 | sbc8g | |
|
4 | df-nel | |
|
5 | csbvarg | |
|
6 | 5 5 | eleq12d | |
7 | 6 | notbid | |
8 | 4 7 | syl5bb | |
9 | 2 3 8 | 3bitr3d | |
10 | 1 9 | mto | |
11 | df-nel | |
|
12 | 10 11 | mpbir | |