In this work, written during the Second World War, Popper drew upon themes from his philosophy of science. He criticized those who, like Plato, wished to claim power on the grounds that they had access to secure knowledge. And he criticized those like Marx who had allowed their essential humanitarianism to be channeled into directions that were hostile to the Open Society, because they held false theories of knowledge and of history. Popper's Open Society contains much detailed critical discussion of both Plato and Marx. In addition, it contains Popper's own picture of an Open Society.
Popper is here concerned with the freedom and well-being of all citizens.
He pictures a democracy as functioning very much in the spirit of the scientific community. Politics, for Popper, is a matter of our discovering problems and putting forward tentative solutions to them. Learning from Our Mistakes When Popper was writing, he considered that the big issue after the war would be the defense of the ideals of a free society against those who called them into question, from the left and from the right. Today, however, we may look to Popper's work with a different question in mind. Considered from this perspective, Popper's work does not fit too easily within the usual approaches to politics.