All you need to do is have equality of opportunity. If you give opportunities out sensibly, then society does as well as possible--better than if you give opportunities to people who are undeserving and poorly situated to take advantage. So you get better than zero-sum.

The only trick is you have to do this all the way down--and this is quite a trick because of the huge historical legacy of unequal opportunity leaving lasting impacts on the present (in terms of impoverished communities, influences on culture, and so on).