I disagree. To the extent that normative economic analysis is the application of optimization theory to human issues, there's no reason that the maximand must be GDP.* In principle, there's nothing stopping economists from writing down models that incorporate environmental quality or measures of civil liberties.
In my case at least we did the bolded in my environmental economics class I took. I still think that measuring civil liberties is not an economic issue, and I don't see how or why you could incorporate that into any economic model when there are already frameworks for measuring those in other social sciences. For civil liberties you can go over to Freedom House
and see how they rank countries. Yet I don't see how you can even make something so abstract and subjective as "civil liberties" and graph or model them in the same way that you can GDP or supply/demand. Does something in economics offer them a particular framework that you want added to the discussion? You're right that nothing is stopping them from writing those models, but what would they add even if they did?
|That being said, you've touched on the important point that economists can and should work more often with scientists from other disciplines - environmental scientists, geographers, sociologists, and even linguists - and draw on their expertise. There's a tendency within the profession to shun qualitative analysis, and I think it's ultimately detrimental both to the field itself and its ability to do good in society.|
*Okay, that's being a little loose with things. Generally, in macroeconomic models, you have firms maximizing profits and consumers maximizing utility, and then you put them together and solve for a competitive equilibrium. Maximizing GDP is more of a social planner's problem.
I agree that they should work across disciplines, but that goes for anyone in the social sciences. Honestly I'd say maximizing GDP is an economist's problem, since you can do that mathematically. Maximizing GDP isn't a social problem. However, once you start looking at the implications of that GDP growth, it becomes a political problem, ie how do we redistribute this wealth (or not). Or for another example, rent controls. Rent controls hurt housing availability, which is what an economic analysis of them would say. The question of whether or not that drop in housing availability is worth keeping rent low for low income people is a political question.