Description: A lattice is a poset. (Contributed by NM, 17-Sep-2011)
Ref | Expression | ||
---|---|---|---|
Assertion | latpos | ⊢ ( 𝐾 ∈ Lat → 𝐾 ∈ Poset ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | eqid | ⊢ ( Base ‘ 𝐾 ) = ( Base ‘ 𝐾 ) | |
2 | eqid | ⊢ ( join ‘ 𝐾 ) = ( join ‘ 𝐾 ) | |
3 | eqid | ⊢ ( meet ‘ 𝐾 ) = ( meet ‘ 𝐾 ) | |
4 | 1 2 3 | islat | ⊢ ( 𝐾 ∈ Lat ↔ ( 𝐾 ∈ Poset ∧ ( dom ( join ‘ 𝐾 ) = ( ( Base ‘ 𝐾 ) × ( Base ‘ 𝐾 ) ) ∧ dom ( meet ‘ 𝐾 ) = ( ( Base ‘ 𝐾 ) × ( Base ‘ 𝐾 ) ) ) ) ) |
5 | 4 | simplbi | ⊢ ( 𝐾 ∈ Lat → 𝐾 ∈ Poset ) |