The quote from Cormac McCarthy's "No Country for Old Men" reflects a contemplative view on happiness and life experiences. It suggests that by the time one reaches adulthood, their capacity for happiness is largely set. While life's journey includes both joyful and challenging moments, the overall level of contentment remains relatively unchanged. This perspective acknowledges the constancy of our emotional states as we navigate through life.

The speaker implies that some people struggle to find happiness and may remain stuck in their unhappiness, lacking the ability to adapt or find joy. This notion emphasizes the complexities of human experience and the idea that time may not necessarily lead to greater happiness for everyone. Ultimately, McCarthy presents a poignant observation about the human condition, suggesting that individual responses to life's challenges play a crucial role in determining overall satisfaction.