Description: Deduction substituting both sides of an implication, with ph and x disjoint. See also sbimd . (Contributed by Wolf Lammen, 6-May-2023) Revise df-sb . (Revised by Steven Nguyen, 6-Jul-2023)
Ref | Expression | ||
---|---|---|---|
Hypothesis | sbimdv.1 | |- ( ph -> ( ps -> ch ) ) |
|
Assertion | sbimdv | |- ( ph -> ( [ t / x ] ps -> [ t / x ] ch ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | sbimdv.1 | |- ( ph -> ( ps -> ch ) ) |
|
2 | 1 | alrimiv | |- ( ph -> A. x ( ps -> ch ) ) |
3 | spsbim | |- ( A. x ( ps -> ch ) -> ( [ t / x ] ps -> [ t / x ] ch ) ) |
|
4 | 2 3 | syl | |- ( ph -> ( [ t / x ] ps -> [ t / x ] ch ) ) |