Description: Add two antecedents to a wff. (Contributed by Jeff Hankins, 4-Aug-2009)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | a1i14.1 | |- ( ps -> ( ch -> ta ) ) |
|
| Assertion | a1i14 | |- ( ph -> ( ps -> ( ch -> ( th -> ta ) ) ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | a1i14.1 | |- ( ps -> ( ch -> ta ) ) |
|
| 2 | 1 | a1dd | |- ( ps -> ( ch -> ( th -> ta ) ) ) |
| 3 | 2 | a1i | |- ( ph -> ( ps -> ( ch -> ( th -> ta ) ) ) ) |