Wriing history is made more difficult if we do not accept the axiom which opens Wittgenstein's Tractatus: "The world is all that is the case", or the recommendation he gives at the end, to throw away the ladder climbed in order to reach his conclusions. If the world is not given (the case) but a restless terrain of becoming and conflict, it is no longer possible to write its history as a map of certainties. And if on the other hand we cannot abstract certainty from flux, then we are condemned to climb repeatedly back down the ladder to sample once more both the contingency of the world and the emotional and perceptual turmoil "where all the ladders start / In the foul rag and bone shop of the heart" (Yeats). Theory differs from philosophy because it is premised on this repetitive return to a materiality which is never fully ascertainable. Materialism is an incomplete project because it cannot extrapolate an idea from the world without going once more back into the world to confirm the materiality of the idea. This does not mean that it fails; merely that it cannot claim the purity of philosophy's logic, or for that matter the apparent certainties of scientific data. Nor does it imply that no knowledge is possible. It means rather that theoretical knowledge is processual, tentative, falsifiable and dialectical, forged in the contradiction between formal rationality and the constantly reforming world.
Wittgenstein's 'world' is wholly actual; Bergson's fundamentally virtual. Materialist historiography understands that the actuality of the world at any moment is the result of previous virtual potentialities, and contains within it as many more. Kant recognised the contingency of this situation, the vast ocean of interacting elements producing humanly unforeseeable new states in and of the world. For Kant, reason is what separates us from that contingency and so permits us to be free. Materialist theory recognises that we who are subjects of knowledge are contingent; that the reason through which we know is contingent: and that our separation from the world, while perfectly actual, is also the result of previous contingencies. With that knowledge, we know both that we exist actually, but virtually too, in that we are constantly becoming other, and our ideas of reason and our relation with the world likewise. This makes writing history, especially the history of the media through which we know, represent and communicate with the world, significant not for what it tells us about the past, but for what we learn about our possible futures.
What we can speak about we must not pass over in silence.