However, there are also contingent but pervasive facts about human beings that pull in favor of practices that have the foreseen consequence of material inequality. First of all, higher levels of overall welfare can require higher levels of productivity (think of the welfare gains resulting from improvements in agricultural productivity). In many areas of the economy, the provision of material rewards for greater productivity seems the most efficient acceptable way of eliciting higher productivity. Some individuals and groups will be more productive than others (especially if there are incentive schemes). So the practice of providing material rewards for greater productivity will result in material inequality.