In Joan Didion's "Blue Nights," she reflects on the fleeting nature of interest and engagement in life. She captures the contrast between moments of vibrant enthusiasm, where one actively engages with the world through fashion, news, and cultural events, and moments of detachment, where these once-enjoyed pursuits become irrelevant. This rapid shift illustrates how our sense of possibility can be lost in an instant, leaving us feeling disconnected and disinterested in the very things that once captivated us.

Didion emphasizes the importance of maintaining a sense of connection to the world around us. She portrays the poignant realization that what once brought joy and perspective can swiftly change to indifference. This message serves as a reminder of the fragility of our engagement with life and the impact it has on our well-being, suggesting that when we lose our vision of what is possible, we may find ourselves slipping away from meaningful experiences and connections.