It is a common refrain, repeated often by the religious right, in our modern "liberal hedonist times", the maxim usually (falsely) attributed to Dostoyevsky in Brother's Karamazov that if God doesn't exist, than everything is permitted is especially true. From millions killed in Gulags, up to animal sex and *gasp* gay marriage: this is where we end if we deny all transcendent authority that poses unsurpassable limits to human behavior. In absence of this, there is no obstacle to exploit one's neighbor, use them as tools, or even worse, have anal sex with them or kill them.
Jacques Lacan, I think, has probably the best rejoinder to this simplistic analysis: "Quite evidently, a naïve notion, for we analysts know full well that if God doesn't exist, then nothing at all is permitted any longer. Neurotics prove that to us every day."*
The absence of God as a transcendental superego means the buck stops with you. Thus, you are responsible for the consequences of all your actions, and there is no paternal figure to set right was is wrong, or to absolve you of your guilt. That responsibility is yours and yours alone.
This is why any self-reflective atheist is incredibly self-conscious of their own actions. We build a a very complex set of self-imposed limitations and behavioral restraints, ever conscious that this is the one and only life, and our actions can have permanent consequences. And, conversely, it is the religious fundamentalist, in perceiving a totalizing meaning for existence and the state of the world, conceives of himself as an instrument of this higher purpose, and thus is free to do whatever he feels is necessary to fulfill that higher purpose, free of guilt or shame.
What say you, NSG?
* Jacques Lacan, The Ego in Freud's Theory and in the Technique of Psychoanalysis, New York: Norton 1988, p. 128.
