“Analyzing an entity in itself acquaints us only with its components. But a phenomenological study of essences claims to achieve more. It also includes the discovery of certain essential relationsships or connections pertaining to such essences. It is this kind of relationships which is involved when we use such phrases as “it is of the essence (or: in the nature) of,” or “it belongs to the essence (or: part of the essence) of”; also, the adverb “essentially” usually point to such relationships”.
the phenomenological movement. a historical introduction by herbert spiegelberg, essentials of the method, page 699. martinus nijhoff publishers 1984, the hague/boston/lancaster.