From “The Invention of Influence”

Freud could never be certain, he said,

in view of   his wide and early reading,

whether what seemed like a new creation

might not be the work instead

of   hidden channels of memory leading

back to the notions of others absorbed,

coming now anew into form

he’d almost known within him was growing.

He called it (the ghost of a) cryptomnesia.

So we own and owe what we know.