Lord of the Flies, by William Golding

The book tells the story of the cultural and emotional regression (degradation) of a group of young English school-boys that are by accident all alone on a deserted island. Some philosophical reasonings come to attention: hedonism versus responsibility, self versus group, death morality versus group adherence, innocence versus savagery.
The author leaves children to play and evolve under our eyes, their simple and rudimentary decisions become, at a smaller scale, the decisions of the modern civilization.