Childhood (a first caterpillar stage) culminates in a metamorphosis during adolescence… This is a second caterpillar stage. It culminates in the midlife metamorphosis, which gives birth to the true self.
Stein articulates a schema of two (or three) major metamorphoses in the lifespan — adolescence and midlife — each marking a structural discontinuity in psychic identity analogous to the caterpillar-to-butterfly transformation.
, Transformation Emergence of the Self (Volume 7) (Carolyn, 1998thesis