Description: Bound-variable hypothesis builder for class substitution. (Contributed by NM, 5-Aug-1993) (Revised by Mario Carneiro, 12-Oct-2016)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | nfsbc1.1 | |- F/_ x A |
|
| Assertion | nfsbc1 | |- F/ x [. A / x ]. ph |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | nfsbc1.1 | |- F/_ x A |
|
| 2 | 1 | a1i | |- ( T. -> F/_ x A ) |
| 3 | 2 | nfsbc1d | |- ( T. -> F/ x [. A / x ]. ph ) |
| 4 | 3 | mptru | |- F/ x [. A / x ]. ph |