In Cormac McCarthy's novel "All the Pretty Horses," the character warns a gentle knight about the dangers of reason. This statement emphasizes that rationality can sometimes be more destructive than obvious threats or monsters. It suggests that the logical mind can lead to disillusionment and a loss of connection with deeper, more elemental truths.

This quote encapsulates a central theme of the book, which navigates the tension between romanticism and harsh reality. The gentle knight represents an idealistic view, while the caution against reason highlights the complex struggles faced by characters in their pursuit of authenticity and meaning in a challenging world.