In Iain M. Banks' novel "Inversions," the idea that selfishness is the only true sin is explored through the interactions of characters and their moral choices. The narrative weaves complex themes of altruism versus self-interest, highlighting how actions motivated by selflessness can elevate society, while those driven by selfish desires can lead to moral decay. It challenges readers to reflect on the impact of personal motivations on the broader community.

This quote serves as a profound reminder that our ethical standings are often tested by our willingness to prioritize others' needs over our own. It suggests that the measure of a person's character lies fundamentally in their capacity to act for the greater good, rather than merely seeking their own benefits. The examination of these themes in the story encourages introspection about one's own values and the societal implications of selfish versus selfless behaviors.