"The great advantage of being a writer is that you can spy on people. You're there, listening to every word, but part of you is observing. Everything is useful to a writer, you see - every scrap, even the longest and most boring of luncheon parties"

Graham Greene's quote highlights the unique position writers keep in society and the creative process. He describes this function as that of an observer or even a spy, discreetly suggesting that authors have the capability to gather insight and motivation from the world around them. This perspective encapsulates the dual nature of being an active individual and a separated observer. As an author, you are implanted in daily experiences, conversations, and environments, yet possess the capability to go back and evaluate these components objectively.

Greene recommends that every experience, no matter how mundane, holds potential for motivation. The phrase "every scrap, even the longest and most dull of luncheon parties", stresses how authors can extract worth from all experiences, even those moments that may appear insignificant or tedious to others. This quality enables writers to dive deeper into the human experience, recording nuances and details that bring credibility and richness to their writing.

Additionally, Greene's usage of the term "spy" highlights a particular level of discretion and curiosity intrinsic in the author's approach. In some methods, this positions the author as an eternal trainee of human behavior, motivated by an insatiable quest for understanding. The writer, through observation, gains insights into human inspirations, feelings, and interactions, which can then be woven into their stories.

Eventually, Greene's quote serves to remind us of the writer's capability to change everyday life into art. It recommends that motivation is universal, waiting to be discovered by those attuned to its subtle cues. Hence, the writer's skill depends on their capability to harness these observations, transforming them into compelling stories that resonate with reality and psychological depth. This lens enriches the writer's craft and lights up the intricacy and beauty concealed within normal life.