In Hegel, the term Aufhebung has the apparently contradictory implications of both preserving and changing (the German verb aufheben means both "to cancel" and "to keep"). 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, determinateness, or quality, and magnitude, or quantity, are each both preserved and sublated in the concept measure.
For Hegel, history (like logic) proceeds in every small way through sublation. For example, the Oriental, Greek and Roman Empires (in which the individual is ignored or annihilated, then recognized, and finally suppressed by the States) are preserved and destroyed in the German Empire, which, for Hegel, placed the individual in harmony with the State.
At the level of social history, sublation can be seen at work in the master-slave dialectic.
Hegel approached the history of philosophy in the same way, arguing that important philosophical ideas of the past are not rejected but rather preserved and changed as philosophy develops.
Instead, Hegel calls on speculative thought: two contradictory elements are held together, uplifted and sublated without completely destroying one another. Speculative thought seeks to avoid the idealism inherent in reflective thought and allows one to think in concrete terms about how things work, both in the present, real world and in history.