At the risk of starting something with religion...
Lev Tolstoy (yeah, I like Russian literature) once wrote an essay called What is religion and of what does its essence consist?" You are dying to rush out and buy that one, I bet! One caveat here: I am not so preoccupied with absence of religion (at all, seriously), but one passage has stuck with me for many years:
The main reason for the terrible cruelty between men today, apart from the absence of religion, is still the refined complexity of life which shields people from the consequences of their action. However cruel Attila, Genghis Khan and their followers may have been, the act of killing people personally, face to face, must have been unpleasant to them, and the consequences of the murder still more unpleasant: the wailing relatives and the presence of the corpses. And thus their cruelty was restrained. Nowadays we kill people through such a complex process of communication, and the consequences of our cruelty are so carefully removed and concealed from us, that there is no restraint on the bestiality of the action. The cruelty of some people towards others will continue to increase until it has reached unprecedented dimensions.
Lev wrote this in 1902. I wonder what he meant by the word "communication," or if that is even the exact word he used in Russian. I pass along the quote because it has always made me think about the complexity of our relationships with each other. And, to put it simply, it seems like a good starting point.