Constitutional economics is a domain of inquiry and discourse among scientists who choose to perceive social interaction as a set of complex relationships, both actual and potential, among autonomous persons, each of whom is capable of making rational choices. The domain, as such, cannot be extended to include inquiry by those who choose to perceive social action differently. There is simply no common basis for scientific argument, and ultimately agreement, with those who choose to perceive social interaction either in purely conflictual or purely idealistic visions. These visions are, indeed, alternative 'windows' on the world. And the process through which individuals choose among such windows remains mysterious. How can empirical evidence be made convincing when such evidence must, itself, be perceived from only one vantage point at a time? The naivete of modern empirical economists in this respect verges on absurdity.
James M. Buchanan (1990:17)