يشترط الاتحاد بحسب الوجود ليصح الحمل، والتغاير بحسب المفهوم ليفيد
Predication requires unity in what is referred to; informative predication also involves different meanings.
الإنسان كاتب — A human is a writer. “Human” and “writer” can refer to the same individual while conveying different notions.
الإنسان حجر — A human is a stone. Taken as ordinary literal predication, the required identity of the subject and predicate does not hold.
This helps explain divine predicates such as “knowing” and “powerful”: one subject and distinguishable meanings. But the reasoning must not be transferred carelessly from derivative predicates to the attributes themselves.