On Thu, 28 Jul 2005, Spencer J. Pack apparently wrote:   
> If economics is a theory of choice, then how is it   
> different from psychology?   
  
I do not know what 'theory' means here. Leaving that   
aside...  
  
If you define choice to mean rational choice (and not just   
an action interpreted as choosing), then some might say that   
microeconomists study choice and behavioral psychologists   
study behavior.  (Let us not worry too much about the nature   
of 'rationality' or the meaning of 'behavior' right now.)  
  
Some might perhaps find it more natural to propose that   
microeconomists study rational action while behavioral   
psychologists study action.  
  
Either way, the puzzle remains why economists would restrict   
their permissible explanations relative to the field of   
behavioral psychology.  It seems to me that efforts by   
economists to explore this puzzle have recently been bearing   
some nutritious fruit, as with the rise of behavioral   
economics.  
  
Cheers,  
Alan Isaac