This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Description: Contraposition law for polarity. (Contributed by NM, 23-Mar-2012) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | 2polss.a | ⊢ 𝐴 = ( Atoms ‘ 𝐾 ) | |
| 2polss.p | ⊢ ⊥ = ( ⊥𝑃 ‘ 𝐾 ) | ||
| Assertion | polcon2N | ⊢ ( ( 𝐾 ∈ HL ∧ 𝑌 ⊆ 𝐴 ∧ 𝑋 ⊆ ( ⊥ ‘ 𝑌 ) ) → 𝑌 ⊆ ( ⊥ ‘ 𝑋 ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | 2polss.a | ⊢ 𝐴 = ( Atoms ‘ 𝐾 ) | |
| 2 | 2polss.p | ⊢ ⊥ = ( ⊥𝑃 ‘ 𝐾 ) | |
| 3 | 1 2 | 2polssN | ⊢ ( ( 𝐾 ∈ HL ∧ 𝑌 ⊆ 𝐴 ) → 𝑌 ⊆ ( ⊥ ‘ ( ⊥ ‘ 𝑌 ) ) ) |
| 4 | 3 | 3adant3 | ⊢ ( ( 𝐾 ∈ HL ∧ 𝑌 ⊆ 𝐴 ∧ 𝑋 ⊆ ( ⊥ ‘ 𝑌 ) ) → 𝑌 ⊆ ( ⊥ ‘ ( ⊥ ‘ 𝑌 ) ) ) |
| 5 | 1 2 | polssatN | ⊢ ( ( 𝐾 ∈ HL ∧ 𝑌 ⊆ 𝐴 ) → ( ⊥ ‘ 𝑌 ) ⊆ 𝐴 ) |
| 6 | 5 | 3adant3 | ⊢ ( ( 𝐾 ∈ HL ∧ 𝑌 ⊆ 𝐴 ∧ 𝑋 ⊆ ( ⊥ ‘ 𝑌 ) ) → ( ⊥ ‘ 𝑌 ) ⊆ 𝐴 ) |
| 7 | 1 2 | polcon3N | ⊢ ( ( 𝐾 ∈ HL ∧ ( ⊥ ‘ 𝑌 ) ⊆ 𝐴 ∧ 𝑋 ⊆ ( ⊥ ‘ 𝑌 ) ) → ( ⊥ ‘ ( ⊥ ‘ 𝑌 ) ) ⊆ ( ⊥ ‘ 𝑋 ) ) |
| 8 | 6 7 | syld3an2 | ⊢ ( ( 𝐾 ∈ HL ∧ 𝑌 ⊆ 𝐴 ∧ 𝑋 ⊆ ( ⊥ ‘ 𝑌 ) ) → ( ⊥ ‘ ( ⊥ ‘ 𝑌 ) ) ⊆ ( ⊥ ‘ 𝑋 ) ) |
| 9 | 4 8 | sstrd | ⊢ ( ( 𝐾 ∈ HL ∧ 𝑌 ⊆ 𝐴 ∧ 𝑋 ⊆ ( ⊥ ‘ 𝑌 ) ) → 𝑌 ⊆ ( ⊥ ‘ 𝑋 ) ) |