What makes this line transcendent isn't the romance of chance meeting, but rather the speaker's sudden awareness that he is no longer the author of his own story—fate has rewritten him from protagonist to bystander in his own bar. The genius lies in how Casablanca's writers understood that love isn't about grand gestures but about the vertiginous moment when you realize someone else's presence has retroactively changed the meaning of every ordinary day you've spent in that place. In real life, this captures why we sometimes feel unsettled when someone from our past reappears; they don't just arrive in the present—they cast a shadow backward, making us reconsider whether all our previous solitude there was actually loneliness. The quote endures because it acknowledges what we rarely admit: that randomness in human connection is both thrilling and deeply disorienting.