An element of the fate versus free will dichotomy can be seen in the decisions that characters make and the way that those decisions lead to a very definite fate that results in tragedy. Although fate versus free will is a theme that can be seen much more clearly in Oedipus Rex, in Antigone it is expressed through the choices that characters make and what those choices signify, which result in no uncertain terms in tragic fates for all the characters. This is of course most clearly shown in the central character, Antigone herself. Note how she describes Creon's edit in the opening scene to Ismene:
disobeys in the least will die, his doom is sealed:
stoning to death inside the city walls!
The phrasing of "his doom is sealed" is particularly resonant of fate: Sophocles is making it very clear that actions have definite consequences, and if Antigone chooses to bury her brother's corpse, she will die a premature death. However, for Antigone, there is no choice. Her character and her determination to see her brother honoured before the gods means that she will die, no matter what anybody says. In the same way, Creon's determination to show his power by making the edict in the first place dooms him to a very unhappy life, as it results in Antigone's death which in return results in his own son's death. In each of the main characters, their own qualities seem to doom them to a definite fate that they have no control over whatsoever.