The principal themes of Farewell, My Lovely are summed up by Marlowe toward the end of the story. Explaining to Anne Riordan the motivations behind the acts of Malloy and Lewin Lockridge Grayle, he tells her that their actions were prompted by love, an emotion and basic motivator that cannot be rationally explained.
It is characteristic of Chandler (often accused of sentimentality) that this story, so loaded with murder, violence, and corruption, is essentially a love story. In his determination to move the detective novel from the stale and formalized approach in which every action has an explanation, no matter how forced and contrived its logic, Chandler infused his stories with romantic (therefore sentimental) elements. What else is Marlowe but the modern romantic hero, tilting at the modern windmills of crime, murder, and corruption?
At the same time, however, Chandler’s deft characterizations, realistic settings, and hard, stripped-down language prevented his fiction from sliding into the realm of mawkishness. By having Marlowe acknowledge and mock his own streak of sentimentality, Chandler validates his use of it. In contrast to Malloy’s simple and unreflective motivation, Marlowe’s basis for action and judgment is a complex combination of feeling tempered by careful consideration. That he is also capable of acting on impulse, as in his initial encounter with Malloy, enables him to understand Velma’s death, Malloy’s search, and Lewin Grayle’s devotion. He knows that these basic motivators, which often defy rationality and which precipitated so much destruction, are also the ones that often account for the decent acts performed in a not-so-decent world. It is a hard-won bit of truth, and for Marlowe, a truth well worth the struggle.