Description: A part of a Tarski class strictly dominated by the class is an element of the class. JFM CLASSES2 th. 2. (Contributed by FL, 22-Feb-2011) (Proof shortened by Mario Carneiro, 20-Sep-2014)
Ref | Expression | ||
---|---|---|---|
Assertion | tskssel |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | sdomnen | ||
2 | 1 | 3ad2ant3 | |
3 | tsken | ||
4 | 3 | 3adant3 | |
5 | 4 | ord | |
6 | 2 5 | mpd |