In choosing between alternative feasible allocations, welfare economics espouses the cause of that allocation which maximizes social welfare
A fundamental concern of welfare economics, as of other evaluative ethical theories, resides in the assessment of the goodness of a given state of affairs. In the context of economic investigation, it is convenient to describe a state of affairs very simply in terms of a given feasible allocation of goods among the individuals constituting the economy under review. In assessing the allocation of goods which comes to pass, some criterion of evaluation must obviously come into play. A criterion that welfare economics has been much concerned with is that of Pareto efficiency—named after the Italian sociologist Vilfredo Pareto.