Aufheben (ˈʔaʊ̯fˌheːbm̩, -bən) or Aufhebung (ˈaʊ̯fˌheːbʊŋ) is a German word with several seemingly contradictory meanings, including "to lift up", "to abolish", "cancel" or "suspend", or "to sublate". The term has also been defined as "abolish", "preserve", and "transcend". In philosophy, aufheben is used by Hegel in his exposition of dialectics, and in this sense is translated mainly as "sublate". (Jacques Derrida's preferred French translation of the term was relever.) In Hegel, the term Aufhebung has the apparently contradictory implications of both preserving and changing, and eventually advancement (the German verb aufheben means "to cancel", "to keep" and "to pick up"). The tension between these senses suits what Hegel is trying to talk about. In sublation, a term or concept is both preserved and changed through its dialectical interplay with another term or concept. Sublation is the motor by which the dialectic functions. Sublation can be seen at work at the most basic level of Hegel's system of logic. The two concepts Being and Nothing are each both preserved and changed through sublation in the concept Becoming. Similarly, in the Science of Logic (Doctrine of Being) determinateness, or quality, and magnitude, or quantity, are each both preserved and sublated in the concept measure. Hegel's philosophy of history stresses the importance of negative (the antithesis) in history—negative includes wars, etc., but not only. His conception of historical progress follows a dialectic spiral, in which the thesis is opposed by the antithesis, itself sublated by the synthesis. Hegel stated that aufheben is uniquely exempt from the historical process in that it is supposed to be true for all time and never changes or develops further as in das absolute Wissen ("absolute knowledge"). The synthesis both abolishes and preserves the thesis and the antithesis, an apparent contradiction which leads to difficulties in interpreting this concept (and to translate aufheben). In Hegel's logic self-contradiction is legitimate and necessary.