| Metamath Proof Explorer |
< Previous
Next >
Nearby theorems |
||
| Mirrors > Home > MPE Home > Th. List > ssid | Structured version Visualization version GIF version | ||
| Description: Any class is a subclass of itself. Exercise 10 of [TakeutiZaring] p. 18. (Contributed by NM, 21-Jun-1993.) (Proof shortened by Andrew Salmon, 14-Jun-2011.) |
| Ref | Expression |
|---|---|
| ssid | ⊢ 𝐴 ⊆ 𝐴 |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | id 22 | . 2 ⊢ (𝑥 ∈ 𝐴 → 𝑥 ∈ 𝐴) | |
| 2 | 1 | ssriv 3987 | 1 ⊢ 𝐴 ⊆ 𝐴 |
| Copyright terms: Public domain | W3C validator |