When a world-wide super computer is wired into everyones brains, "Perfect Knowledge" will have been achieved and Communism may work. I hope to never live in that world.
In the mean time, all I gotta do is ask the bar tender for what I want, and BINGO! I gotta Bud.
Communism's use of "perfect knowledge" to plan everything is just an inefficient effort at eliminating my efficient judgment.
Ludwig von Mises demolished the "perfect knowledge" conceit in his book Socialism. That was 1922. It would be nice if we could move on to some other rationalization for economic lunacy, after a mere eighty years. Sigh.
Freedom, Wealth, and Peace,
Francis W. Porretto
Visit The Palace Of Reason: http://palaceofreason.com
For all intents and purposes, the commissar's knowledge was "perfect" as well: he knew he wanted size 11 shoes, and it was illegal to counteract his decisions. (For now let's assume the commissar is honest and intelligent.)
The commissar probably had a size 9 shoe factory out there someplace, too, so theoretically the shoe needs would have been satisfied by the set of factories.
The real problem has to do with allowable responses to imperfect knowledge. For example, the commissar may not have knowm of the corrupt factory manager over at Size 9. Nor, perhaps, of the flood that disrupted the transport of size 6 shoes from the factory to the distribution points.
Given the freedom to respond, the Size 11 plant could have covered the size 9 shortfall. But the system didn't allow it.