The task of the political economists is to assess alternative institutional arrangements with respect to their impact on the ability of free individuals to realize peaceful social cooperation and productive specialization. This does require mastery of the technical principles of the discipline of economics, which not everyone can possess. But with those tools in their possession, the economist still does not have any claim to privilege position in the democratic decision process that constitutes collective action. All he can do is offer his proposed reforms as hypotheses to be tested in the public conversation. He can try to persuade his fellow citizens of the value of his perspective, but he has no expert claim to impose his solutions on the body politic. Buchanan's work is both a counsel of humility while also being a cause for hope that reform can improve our situation.
We economists must stay humble in our role as observers of society. We are certainly not social engineers or social planners with any advanced understanding of how to manipulate people within an economy.