Peter Cole said this quote

“ Freud could never be certain, he said,in view of   his wide and early reading,whether what seemed like a new creationmight not be the work insteadof   hidden channels of memory leadingback to the notions of others absorbed,coming now anew into formhe’d almost known within him was growing.He called it (the ghost of a) cryptomnesia.So we own and owe what we know. ”