In the quote from Hilary Mantel's "An Experiment in Love," the speaker reflects on the struggle of navigating personal boundaries and societal expectations. Their admission of not knowing where the metaphorical line is suggests a sense of confusion and uncertainty in their life. This lack of understanding drives them to step out of conventional norms, indicating a desire for exploration and authenticity, even amidst the risks involved.

The quote captures a universal experience of feeling lost and the internal conflict that arises from it. The author's phrasing emphasizes that ignorance, rather than willfulness, often leads one to challenge limits. It resonates with readers by highlighting the courage it takes to venture into the unknown while grappling with the need for guidance and clarity.