Scalzi's book starts from a well explored premise: the abundance of life in the universe makes its finite resources a scarce commodity, and therefore the space-faring species are engaged in battles to share them. The metaphor to the way humans must learn to share Earth's finite resources is obvious but not gratuitous. The interesting take is on what makes us human: what is the relationship between our consciousness, our experience, and our body? Well written and engaging, a bit too humorous at times, but nevertheless a very good read for lovers of SF.