Income disparity and need for continuous growth are not strictly dependent on each other. Assume that everyone was given exactly equal portion of global GDP. This will still end up everyone at $9/hr. While this might be above poverty line, no one would be able to afford virtually any expensive technological advances. The bottom line is that current total world GDP is not sufficient to experience full technological advances by all humans which calls for further growth.
> When it gets down to it–we're talking trade balances here–once we've brain-drained all our technology into other countries, once things have evened out, they're making cars in Bolivia and microwaves in Tadzhikistan and selling them here–once our edge in natural resources has been made irrelevant by giant Hong Kong ships and dirigibles that can ship North Dakota all the way to New Zealand for a nickel–once the Invisible Hand has taken all those historical inequities and smeared them out into a broad global layer of what a Pakistani bricklayer would consider to be prosperity–y'know what? There's only four things we do better than anyone else: music, movies, microcode (software), high-speed pizza delivery.
