How is "discriminating against a group" different from "balancing its overwhelming predominance in a particular field"? The dictionary definition of "discrimination" says there's no difference. Is the definition that says there is a difference some sort of a moral standard? What are the thresholds of that standard - at what point group members outdoing others warrants affirmative action and by how much the numbers of those members should be dwindled by affirmative action? Which groups should be punished by affirmative action - ethnic and gender, or is religion a legitimate target, what about height, family history, a preference to wear clothes of a certain color - whom is it OK to count and then hold to a higher standard to balance their overwhelming predominance?

Also - what cost should society pay in lost output due to the average ability of people allowed to enter certain occupations having been lowered by affirmative action (as it has to be if less capable candidates are admitted instead of more capable)?

Perhaps most interestingly - how much cost should a group supposedly "helped" by affirmative action pay for the dubious favor in (A) people being unable to successfully function at institutions who admitted them, not because of their abilities, but due to affirmative action and (B) perfectly capable people of the "helped" group being stigmatized because "everyone knows they only got to where they were due to affirmative action, and not due to their ability?"

(I guess you might notice that I'm not a huge fan of affirmative action, but if we could at least agree that there's no reasonable way to distinguish between "affirmative action" and "discrimination", that would be in itself awesome, even if we disagree about the merit of, well, that one thing with two names...)