This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Description: A word over an alphabet is a word over the universal class. (Contributed by AV, 8-Feb-2021) (Proof shortened by JJ, 18-Nov-2022)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | wrdv |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | ssv | ||
| 2 | sswrd | ||
| 3 | 1 2 | ax-mp | |
| 4 | 3 | sseli |