| Metamath Proof Explorer |
< Previous
Next >
Nearby theorems |
||
| Mirrors > Home > MPE Home > Th. List > df-fal | Structured version Visualization version GIF version | ||
| Description: Definition of the truth value "false", or "falsum", denoted by ⊥. See also df-tru 1573. (Contributed by Anthony Hart, 22-Oct-2010.) |
| Ref | Expression |
|---|---|
| df-fal | ⊢ (⊥ ↔ ¬ ⊤) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | wfal 1582 | . 2 wff ⊥ | |
| 2 | wtru 1571 | . . 3 wff ⊤ | |
| 3 | 2 | wn 3 | . 2 wff ¬ ⊤ |
| 4 | 1, 3 | wb 209 | 1 wff (⊥ ↔ ¬ ⊤) |
| Colors of variables: wff setvar class |
| This definition is used by: fal 1584 nottru 1597 trunortru 1619 trunorfal 1620 empty 1939 bj-fal 37254 bj-cbvaew 37359 ralfal 45978 |
| Copyright terms: Public domain | W3C validator |