Abstract
This paper deals with the well known Basic Theorems of Welfare Economics from a view of Public Choice. The conventional Pareto Optimality of the Basic Theorems is defined by the only obligatory conditions. The changes from a society with no facultative conditions to that with both facultative and obligatory conditions are considered under the Theorems. But any changes except those from the existing rules and institutions are impossible in the real world. The First Basic Theorem is criticized from Buchanan's approach and the Second One is disapproved by allowing for Tullock's cost of transfers.
The extention of the conventional Pareto Optimality concept to the changes of rules and institutions are called as Buchanan Optimality. We consider some charactaristics of Buchanan Optimality and Public Choice approach compared to the conventional Pareto Optimality criterion.
