NZPols has a good post on the slipperiness of equality as a concept. I'll admit to sloppiness, and it should be clear from my post that I'm after a more substantive equality than the narrow, formal sense being propagated by Brash and his ilk. This involves both equality of life-chances (a minimisation of the effects of life's various lotteries, at least on the losers) mixed with big, fat globs of well-being and (self-regarding) preference-satisfaction.

The Amartya Sen article, "Equality of what?", can be found online here.