“We interact with one another as individuals responding to a complex haze of factors: professional responsibilities, personal likes and dislikes, ambition, jealousy, self-interest, and, in at least some instances, genuine altruism. Living in the here and now, we are awash with sensations of the present, memories of the past, and expectations and fears for the future. Our actions are not determined by any one cause; they are the fulfillment of who we are at that particular moment. After that moment passes, we continue to evolve, to change, and our memories of that moment inevitably change with us as we live with the consequences of our past actions, consequences we were unaware of at the time.”