Why Amartya Sen likes Prof James Buchanan's theory of public reasoning?

Meeting different people is not all that bad even if some one is really thinking differently about them. I had brief opportunity to meet Prof Sen early this month. He had mentioned about one of his new article and that is the one I am citing here. It is worth to read the entire article for the below para alone.

• "Public reasoning is not only crucial for democratic legitimacy, it is essential for a better public epistemology that would allow the consideration of divergent perspectives. It is also required for more effective practical reasoning. It can bring out what particular demands and protests can be restrained in interactive public reasoning, in line with scrutinized priorities between a cluster of quite distinct demands. This involves a process of “give and take” which many political analysts, from Adam Smith and the Marquis de Condorcet in the eighteenth century to Frank Knight and James Buchanan in our time, have made us appreciate better."