'Our demands most moderate are,' sang James Connolly, 'we only want the
> earth'
>
> 'We do not call for limitation of births, for penurious thrift, and
> self-denial', Sylvia Pankhurst wrote. 'We call for a great production that
> will supply all, and more than all the people can consume,'
>
This might not carry much water with James, but mainstream ecology would hold that the Earth cannot support anything close to six billion people with lifestyles remotely approaching that of the average Western worker. An interactive illustration (unfortunately only for Americans and Australians):
http://www.earthday.net/footprint
-- "Hige sceal þe heardra, heorte þe cenre, mod sceal þe mare, þe ure mægen lytlað."