Note 1076 — AN ESSAY ON MAN, IN FOUR EPISTLES (continued 3)

A two-fold or mixed nature was sometimes in old language called a "middle nature," such as a compound of mind and matter, or an amphibious animal, and Pope perhaps meant that the double nature "longs to join" in a more intimate union. Or he may have meant by "middle," an intermediate nature, such as any creature which has an order of beings above and below it, but then to satisfy Pope's phraseology there must be two of these middle natures which are longing to unite with each other, and the higher would not desire to be "joined" to the lower. The couplet seems at best to be mere mystical jargon.