Margaret Wise Brown and the Puzzle of What Makes a Thing Itself (and You Yourself)

Aristotle, Alice, and a back flap.

“What is essential is invisible to the eye,” Antoine de Saint-Exupéry wrote as he contemplated the meaning of life in one of humanity’s greatest works of philosophy disguised as a children’s book.

The challenge, of course, is that what is essential — about the totality of life, as about every littlest thing in it — is not easily visible, largely because nothing is actually reducible, or should be reduced, to an essence: to a single point of truth, a particula...