This is in response to an article by Mike Marqusee, Politics and "the art of the possible", published in today's Guardian under the title, The power of utopianism.
What is possible depends, more than anything else, on our understanding of the issues concerned.
All the wonders of modern technology and what they have made possible (like sending men to the Moon, and probes to the planets, aviation, modern communications, etc.) were complete fantasy before we developed a much deeper understanding, i.e. created ever more realistic models, of the material world than we had before.
The so-called political and social sciences have not advanced as the material sciences have, but are still held up in a pre-Copernican, i.e. pre-Darwinian, stage of development, because of the massive taboos (social, political, professional and psychological) against anyone taking a comprehensive, human-evolutionary, i.e. Darwinian, view of human nature and behaviour patterns, along with the civilizations (the power structures of states and economies) they have given rise to.
Everything (including, most relevantly, our survival) depends on us recognising the Darwinian nature of our situation and developing an understanding of it. Then, all sorts of things will become possible, such the creation of just, humane and sustainable societies, which now we can only dream of . .