Peter Pan syndrome

Puer aeternus (sometimes shortened to puer) Latin for "eternal boy", in mythology, is a child-god who is forever young. In psychology, it is an older person whose emotional life has remained at an adolescent level. The puer typically leads a provisional life, due to the fear of being caught in a situation from which it might not be possible to escape. He covets independence and freedom, opposes boundaries and limits, and tends to find any restriction intolerable.

The words, puer aeternus, come from Metamorphoses, an epic work by the Roman poet Ovid (43 BC – c.17 AD) dealing with Greek and Roman myths. In the poem, Ovid addresses the child-god Iacchus as puer aeternus and praises him for his role in the Eleusinian mysteries. Iacchus is later identified with the gods Dionysus and Eros. The puer is a god of vegetation and resurrection, the god of divine youth, such as Tammuz, Attis and Adonis. The figure of a young god who is slain and resurrected also appears in Egyptian mythology as the story of Osiris.

Swiss psychiatrist Carl Gustav Jung developed a school of thought called analytical psychology, distinguishing it from the psychoanalysis of Sigmund Freud (1856–1939). In analytical psychology (often called "Jungian psychology") the puer aeternus is an example of what Jung called an archetype, one of the "primordial, structural elements of the human psyche".

The shadow of the puer is the senex (Latin for "old man"), associated with the god Cronus—disciplined, controlled, responsible, rational, ordered. Conversely, the shadow of the senex is the puer, related to Hermes or Dionysus—unbounded instinct, disorder, intoxication, whimsy.

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