A world of self-reliant individuals is worse than one in which people specialise. To take the simplest example, if everyone in our Utopia knew just enough to build and maintain their shelter in the morning, hunt animals in the afternoon, and forage for food in the evening, they labour all day. If one-third of people build and maintain housing, another third hunts animals, and the final third forages for food - a person might work perhaps half the day and trade for what else they need. Self-sufficiency is the ideology of the troglodyte.