As promised, I'll now describe the 'argument from market forces' which could be used to justify affirmative action in the workplace.
The core idea is that sometimes members of a particular group (eg a specific race or gender) will be better suited for a job, for the intrinsic reason of having such membership. So I'm not talking about hiring men cos they're stronger (just hire strong people, whether they're men or not is irrelevant), or anything like that. Rather, I'm talking about hiring an Asian, a female, a white person, etc, for the particular reason that they belong to that group. But it must be emphasised that the reason for doing this will not be for the sake of the employee (unlike the arguments from inferiority & superiority), but rather, for the sake of the job/customers.
A couple of examples might make this clearer. A typical example would be customer relations. The Christchurch City Council wants to hire more ethnic minorities (particularly Asians), for the reason that such people would be better able to communicate with, and serve the needs of, (e.g.) Asian clients who contact the CCC with enquiries.
Probably the most pressing example I can think of would be male school teachers - of which there is a disastrously short supply in New Zealand. Some boys are going through primary school without ever having a single male teacher. I don't know exactly what all the psychological & sociological implications of this are, but I hear it's bad news, in any case. Ya know, lack of role models, boys educational needs aren't being met, etc etc.
Anyway, the point is, we desperately need more male teachers. (A similar argument might be made for Maori teachers, though it is probably not so pressing a problem. At least according to the statistics I'm aware of, the gender gap in school performance is much more significant than the race gap.) The answer: entice more males into the profession. A pay raise, special scholarships, it doesn't matter how it's done, so long as it works.
The rationale behind such discrimination is pragmatic, not ideological. Hence the name: "argument from market forces". It's simple supply & demand. In the ideal 'free market' (ya know, that one which exists next to 'perfect circles' in Plato's world of forms), if some skill is in short supply (relative to the demand), then its worth increases. In our case, that "skill" - odd though this sounds - is membership in some particular group. In heavily regulated markets such as the civil service, the government might need to actively advocate such pragmatic discrimination, for the sake of market efficiency.
There are some dangers with this line of argument though. Market forces are driven by customer preferences, and these preferences might not always be justified. In the case of Asian customer relations personnel, or male or maori school teachers, I think it probably is.
But suppose some business' customers were all "black power" racists, and they didn't like to be served by white people. There is clearly a pragmatic market incentive for the managers to hire only black people in such a case. But this seems quite patently unjust. This is one case in which we would probably want the government to step in and prevent any discrimination by market forces. (This intuition is even stronger if you reverse the scenario so that it involves traditional white-supremist racism, but that would weaken the link to "affirmative action".)
So there must be some reasonable justification for thinking that someone of a particular race or gender would be intrinsically preferable for a job. Mere client preference is not always enough. Unfortunately, it's not immediately clear where to draw the line. As always, any suggestions/comments would be most welcome.