Description: A class of surreals has at most one minimum. (Contributed by Scott Fenton, 8-Aug-2024)
Ref | Expression | ||
---|---|---|---|
Assertion | nominmo | ⊢ ( 𝑆 ⊆ No → ∃* 𝑥 ∈ 𝑆 ∀ 𝑦 ∈ 𝑆 ¬ 𝑦 <s 𝑥 ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | sltso | ⊢ <s Or No | |
2 | soss | ⊢ ( 𝑆 ⊆ No → ( <s Or No → <s Or 𝑆 ) ) | |
3 | 1 2 | mpi | ⊢ ( 𝑆 ⊆ No → <s Or 𝑆 ) |
4 | somo | ⊢ ( <s Or 𝑆 → ∃* 𝑥 ∈ 𝑆 ∀ 𝑦 ∈ 𝑆 ¬ 𝑦 <s 𝑥 ) | |
5 | 3 4 | syl | ⊢ ( 𝑆 ⊆ No → ∃* 𝑥 ∈ 𝑆 ∀ 𝑦 ∈ 𝑆 ¬ 𝑦 <s 𝑥 ) |