src/HOL/Cardinals/Wellorder_Constructions.thy
changeset 63540 f8652d0534fa
parent 63167 0909deb8059b
child 66453 cc19f7ca2ed6
equal deleted inserted replaced
63539:70d4d9e5707b 63540:f8652d0534fa
   604   thus False using 1 by (metis ANTISYM antisymD)
   604   thus False using 1 by (metis ANTISYM antisymD)
   605 qed
   605 qed
   606 
   606 
   607 lemma not_isSucc_zero: "\<not> isSucc zero"
   607 lemma not_isSucc_zero: "\<not> isSucc zero"
   608 proof
   608 proof
   609   assume "isSucc zero"
   609   assume *: "isSucc zero"
   610   moreover
       
   611   then obtain i where "aboveS i \<noteq> {}" and 1: "minim (Field r) = succ i"
   610   then obtain i where "aboveS i \<noteq> {}" and 1: "minim (Field r) = succ i"
   612   unfolding isSucc_def zero_def by auto
   611   unfolding isSucc_def zero_def by auto
   613   hence "succ i \<in> Field r" by auto
   612   hence "succ i \<in> Field r" by auto
   614   ultimately show False by (metis REFL isSucc_def minim_least refl_on_domain
   613   with * show False
   615     subset_refl succ_in succ_not_in zero_def)
   614     by (metis REFL isSucc_def minim_least refl_on_domain
       
   615         subset_refl succ_in succ_not_in zero_def)
   616 qed
   616 qed
   617 
   617 
   618 lemma isLim_zero[simp]: "isLim zero"
   618 lemma isLim_zero[simp]: "isLim zero"
   619   by (metis isLim_def not_isSucc_zero)
   619   by (metis isLim_def not_isSucc_zero)
   620 
   620