Description: A simplified satisfaction predicate as function over wff codes over an empty model is an empty set. (Contributed by AV, 31-Oct-2023)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | sate0fv0 | |- ( U e. ( Fmla ` _om ) -> ( S e. ( (/) SatE U ) -> S = (/) ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | 0ex | |- (/) e. _V |
|
| 2 | satef | |- ( ( (/) e. _V /\ U e. ( Fmla ` _om ) /\ S e. ( (/) SatE U ) ) -> S : _om --> (/) ) |
|
| 3 | 1 2 | mp3an1 | |- ( ( U e. ( Fmla ` _om ) /\ S e. ( (/) SatE U ) ) -> S : _om --> (/) ) |
| 4 | 3 | ex | |- ( U e. ( Fmla ` _om ) -> ( S e. ( (/) SatE U ) -> S : _om --> (/) ) ) |
| 5 | f00 | |- ( S : _om --> (/) <-> ( S = (/) /\ _om = (/) ) ) |
|
| 6 | 5 | simplbi | |- ( S : _om --> (/) -> S = (/) ) |
| 7 | 4 6 | syl6 | |- ( U e. ( Fmla ` _om ) -> ( S e. ( (/) SatE U ) -> S = (/) ) ) |