Pseudos / Aletheia

Martin Heidegger writes: 

"To twist a thing" is called pseudesthai by the Greeks. The struggle for the unconcealment of beings, aletheia, thus becomes the struggle against the pseudos, against twisting and distortion. But the essence of struggle implies that the one who struggles becomes dependent on his opponent, whether he conquers him or is defeated by him.
So because the struggle against untruth is a struggle against the pseudos, then the struggle for truth, in contrast to the pseudos against which one is struggling, becomes the struggle for the a-pseudes, the undistorted, the untwisted.

Introduction to Metaphysics (New Haven: Yale University Press, 2000), 205.