Over the course of this economic crisis, I have seen a lot of erroneous analysis based on the conflation of things that are not commensurate. It is getting worse as the debt hysteria mounts. These conflations are examples of category errors, which are common in monetary and macroeconomic analysis. Most of the theoretical development in macroeconomics text books used by universities fall foul of this type of error. The one thing that follows is that when you detect this type of error you should be deeply suspicious of the arguments being presented.