As you read a book word by word and page by page, you participate in its creation, just as a cellist playing a Bach suite participates, note by note, in the creation, the coming-to-be, the existence of the music. And, as you read and re-read, the book of course participates in the creation of you, your thoughts and feelings, the size and temper of your soul.

Ursula K. Le Guin (1929–2018) American writer

Essay (1977-11), “Books Remembered,” Children’s Book Council Calendar, Vol. 36, No. 2
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Quoted in the Epigraph to the Introduction to Part 3 "The Book Is What Is Real" in Le Guin, The Language of the Night: Essays on Fantasy and Science Fiction (1979)