Raymond Geuss at The Point:
At the beginning of the nineteenth century Hegel wrote that every philosopher is a child of his time and none can jump over his own shadow: every philosophy, then, is “its time grasped in a concept.” In the twentieth century Adorno took up this idea again when he spoke of the irreducible “kernel of time” embedded in the center of any philosophical view, and of the “temporal index” of truth. Whatever these rather difficult doctrines mean, they clearly are not intended to imply that at any given time all opinions are equally true.
I started a small book in Heidelberg, Germany in 1973 and finally finished it in 1980 at the University of Chicago; The Idea of a Critical Theory was published by Cambridge University Press in late 1981. Looking back at the text from the present—from 2013 and my home on this small island off the northwest coast of Europe—I think I can begin to see rather more clearly than I could then some of the relevant features of the historical context within which it was conceived and executed. To return for a moment to Hegel, who is the major spiritual presence hovering over this book—and whose work is the more important for understanding what I was trying to do for not being mentioned at all in the main text—the reader will recall that he also holds that philosophy is essentially retrospective, a reflection of a historical moment or movement that when it finally takes philosophical form is essentially already over. This doctrine marks a distinction between what is “really” happening in the political, social and economic world and the subsequent reflection of this in philosophy (religion, art, law, etc.).