:: deftheorem Def32 defines the_right_argument_of ZF_LANG:def 32 :
for H being ZF-formula st ( H is conjunctive or H is disjunctive ) holds
for b₂ being ZF-formula holds
( ( H is conjunctive implies ( b₂ = the_right_argument_of H iff ex H1 being ZF-formula st H1 '&' b₂ = H ) ) & ( not H is conjunctive implies ( b₂ = the_right_argument_of H iff ex H1 being ZF-formula st H1 'or' b₂ = H ) ) );