Michael Perelman asks, "If economics is a theory of choice, tell me how   
workers got to choose their working hours in the 19th C., when they had   
to fight for an 8 hour day?"  
  
Need Michael be told that there is a difference between economic HISTORY   
and economic theory -- explanation of choices people make?  Of course,   
the choices different workers and their prospective employers made in   
different periods of time account for the evolution of the structure of   
formal and informal sectors of economies.  In fact, one need not go back   
to the 19th century to learn this.  One can discover the effects of   
these choices in formal and informal sectors of currently developed and   
less developed countries.  
  
The science of economics -- the explanation of choices people make -- is   
universally applicable, it has been said long ago.  
  
James Ahiakpor