Created
July 15, 2022 01:01
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theory "Well_Not_Dense_Order" imports Main begin | |
context wellorder | |
begin | |
definition bot :: 'a | |
where "bot ≡ LEAST x. True" | |
sublocale order_bot bot less_eq less | |
proof standard | |
fix a | |
show "bot ≤ a" | |
unfolding bot_def by (simp add: local.Least_le) | |
qed | |
lemma no_dense: | |
fixes a :: 'a | |
assumes "a ≠ bot" | |
and "⋀a b. ⟦⋀x. ⟦a ≤ x; x ≤ b⟧ ⟹ thesis; a ≠ b⟧ ⟹ thesis" | |
shows "thesis" | |
using assms le_bot by metis | |
end | |
end |
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