In the book "Possession" by A.S. Byatt, the phrase "by heart" suggests a deep, intrinsic connection to poetry, almost as if it is an integral part of a person's being. This expression highlights the idea that poems can become so familiar and cherished that they inhabit one's very essence, much like blood coursing through veins.
The use of this metaphor emphasizes the profound impact poetry can have on the soul, suggesting that true appreciation of art goes beyond mere memorization. It indicates a visceral relationship with language, where the poems resonate within, shaping thoughts and feelings on a fundamental level.