:: deftheorem Def7 defines MC-closed INTPRO_1:def 7 :
for E being set holds
( E is MC-closed iff ( E c= NAT * & E is with_FALSUM & E is with_int_implication & E is with_int_conjunction & E is with_int_disjunction & E is with_int_propositional_variables & E is with_modal_operator ) );