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| Mirrors > Home > ILE Home > Th. List > nfnth | GIF version | ||
| Description: No variable is (effectively) free in a non-theorem. (Contributed by Mario Carneiro, 6-Dec-2016.) |
| Ref | Expression |
|---|---|
| nfnth.1 | ⊢ ¬ 𝜑 |
| Ref | Expression |
|---|---|
| nfnth | ⊢ Ⅎ𝑥𝜑 |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | nfnth.1 | . . 3 ⊢ ¬ 𝜑 | |
| 2 | 1 | pm2.21i 647 | . 2 ⊢ (𝜑 → ∀𝑥𝜑) |
| 3 | 2 | nfi 1476 | 1 ⊢ Ⅎ𝑥𝜑 |
| Colors of variables: wff set class |
| Syntax hints: ¬ wn 3 ∀wal 1362 Ⅎwnf 1474 |
| This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-ia1 106 ax-ia2 107 ax-ia3 108 ax-in2 616 ax-gen 1463 |
| This theorem depends on definitions: df-bi 117 df-nf 1475 |
| This theorem is referenced by: (None) |
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