Horkheimer and Adorno's book Dialectic of Enlightenment was written in the concluding months of the Second World War. It is comparable with contemporaneous works by other exiled German speaking philosophers, notably Popper's The Open Society and its Enemies and Lukács's The Destruction of Reason, in being what Popper himself described as his “contribution to the war effort.” Comparisons are instructive.

Karl Popper was a philosopher of science and a resident of London. The Open Society traces – from the vantage point of western democracy – the way in which a certain kind of intolerant (and hence “unscientific”) thinking reproduces itself in totalitarian political philosophies: Plato is the ancient representative of this tradition, while its modern representatives Hegel and Marx are discerned, despite their superficial political differences, as the authors of twentieth-century dictatorships of all colors. Györky Lukács, by contrast, wrote as a resident of the Soviet Union and as a metaphysician committed to socialism. For him, Marx, and to a substantial extent Hegel as well, were the fountainheads of an enlightened and humane political system. The strength of “scientific socialism” lay precisely in its incorporation of the insights of dialectical philosophy. Dialectic of Enlightenment differs from the other two works in that it reckons up not merely with philosophy under the Nazis, but also with the unashamed free market capitalism of its authors’ temporary home, the United States. The book is a work of conservative cultural criticism, which, on a conceptual level, is by no means incompatible with work the Nazis were happy to tolerate. This is not to say that it is politically tainted. Of the three books mentioned, however, it offers the least clear alternative to the errors it castigates.