Description: Version of spime with a disjoint variable condition, which does not require ax-13 . (Contributed by BJ, 31-May-2019)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | spimefv.1 | |- F/ x ph |
|
| spimefv.2 | |- ( x = y -> ( ph -> ps ) ) |
||
| Assertion | spimefv | |- ( ph -> E. x ps ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | spimefv.1 | |- F/ x ph |
|
| 2 | spimefv.2 | |- ( x = y -> ( ph -> ps ) ) |
|
| 3 | 1 | a1i | |- ( T. -> F/ x ph ) |
| 4 | 3 2 | spimedv | |- ( T. -> ( ph -> E. x ps ) ) |
| 5 | 4 | mptru | |- ( ph -> E. x ps ) |