Description: The value of the satisfaction predicate as function over wff codes in the empty model and the empty binary relation does not contain the empty set. (Contributed by AV, 19-Sep-2023)
Ref | Expression | ||
---|---|---|---|
Assertion | satf0n0 | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | fveq2 | |
|
2 | 1 | eleq2d | |
3 | 2 | notbid | |
4 | fveq2 | |
|
5 | 4 | eleq2d | |
6 | 5 | notbid | |
7 | fveq2 | |
|
8 | 7 | eleq2d | |
9 | 8 | notbid | |
10 | fveq2 | |
|
11 | 10 | eleq2d | |
12 | 11 | notbid | |
13 | 0nelopab | |
|
14 | satf00 | |
|
15 | 14 | eleq2i | |
16 | 13 15 | mtbir | |
17 | simpr | |
|
18 | 0nelopab | |
|
19 | ioran | |
|
20 | 17 18 19 | sylanblrc | |
21 | eqid | |
|
22 | 21 | satf0suc | |
23 | 22 | adantr | |
24 | 23 | eleq2d | |
25 | elun | |
|
26 | 24 25 | bitrdi | |
27 | 20 26 | mtbird | |
28 | 27 | ex | |
29 | 3 6 9 12 16 28 | finds | |
30 | df-nel | |
|
31 | 29 30 | sylibr | |