I don't know that I'd describe *any* of my positions as my being "so certain" but I do believe that it's the case given the experience of actually existing planned economies in the 20th century that calculation problems are very real (even if you think they can be overcome).

A traditional socialist reply is that these problems arose in the Soviet context because of lack of democracy.

But if you grafted political democracy onto the basic structure of the Soviet economy, while I'm sure that *would* avert the worst horrors of the system (Ukrainian famine, etc.) I'm not convinced it would solve the day to day problems of...