All of the definitions given will give a place from which to start. I  
don't think, however, that a strict definition will be of much use in the  
history of economics. Most the writers we encounter will not stick to  
that definition. In fact most of the writers we are interested in would  
not have defined themselves as "Economists". To understand them we can  
not limit ourselves to a modern definition of economics. To read Locke or  
Smith or Marx or Mill is to ramble through all of those other "disciplines". 
 
On Wed, 28 Jun 1995, Robin Neill wrote: 
 
>      If economics has no definition, we may still practice it, in an 
> unselfconscious way.  If one wants to reflect on Economics, and the 
> History of Economics does, then some idea of the subject of reflection 
> is necessary, however fuzzy it may be.  Selfconsciousness is of the 
> essence of the History of Economics.  How can one ramble through 
> Sociology, Political Science, etc., without some way of distinguishing 
> those disciplines from Economics? 
>