| New Foundations Explorer |
< Previous
Next >
Nearby theorems |
||
| Mirrors > Home > NFE Home > Th. List > olci | GIF version | ||
| Description: Deduction introducing a disjunct. (Contributed by NM, 19-Jan-2008.) (Proof shortened by Wolf Lammen, 14-Nov-2012.) |
| Ref | Expression |
|---|---|
| orci.1 | ⊢ φ |
| Ref | Expression |
|---|---|
| olci | ⊢ (ψ ∨ φ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | orci.1 | . . 3 ⊢ φ | |
| 2 | 1 | a1i 10 | . 2 ⊢ (¬ ψ → φ) |
| 3 | 2 | orri 365 | 1 ⊢ (ψ ∨ φ) |
| Colors of variables: wff setvar class |
| Syntax hints: ¬ wn 3 ∨ wo 357 |
| This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 |
| This theorem depends on definitions: df-bi 177 df-or 359 |
| This theorem is referenced by: falortru 1342 ltcirr 6273 |
| Copyright terms: Public domain | W3C validator |