According, to my understanding, the meaning of dialectic is...
- In Plato: a back-and-forth conversational style of reasoning from his later dialogues
- In the Middle Ages: the scholastic style of reasoning so well exemplified in Aquinas (objection, objection, objection—main point—answer to objection, answer to objection, answer to objection...)
- In Hegel: the historical movement of thesis-antithesis-synthesis, logic played out in history through the movement of the World Spirit
Kierkegaard seems to be consciously responding to Hegel, so the way he redefines his terms (spirit, for example) is important to understanding him.
How does Søren Kierkegaard use the word dialectic? How does his use of it differ from G.W.F. Hegel's? How is it affected by Hegel's sense as opposed to Plato's or the scholastics'?
The sense I'm getting from Kierkegaard is that he means to use it as something like paradoxical reasoning, or tension in thinking, which seems to be distinct from any of the definitions given above. An example is his statement from the beginning of Section C of Part One of The Sickness Unto Death:
Freedom is the dialectical element in the categories of possibility and necessity.
It also seems to him to be divorced from the historical understanding in Hegel.