This discussion seems to have devolved  
into simply a discussion of microeconomics,  
although some have mentioned such issues as  
production, growth, and distribution.  Let  
me note more generally that if one takes at  
all seriously aggregation problems, aka the  
fallacy of composition (which applies to many  
things besides the usual old textbook Keynesian  
investment story), what is going on at the level  
of individual choice, whether it is constrained  
optimization or robotized slavery or whatever,  
may have little to do with a variety of aggregate  
(or macro) phenomena that economists surely do  
study and take seriously, unless of course one  
insists on the supreme reality of the representative  
agent model, which I do not personally.  
       So, this is another reason why the Robbins  
definition is at best limited, however useful it  
may be for large portions of economics.  
  
Barkley Rosser