Final answer:
The defense mechanism represented in this situation is Rationalization, where the person justifies their actions by providing acceptable reasons for their behavior.
Step-by-step explanation:
The defense mechanism that this situation represents is Rationalization. Rationalization is a defense mechanism where a person justifies their behaviors by substituting acceptable reasons for less-acceptable real reasons.
In this case, the patient is rationalizing his actions by explaining that he beat his brother because of the mistreatment he had received in the past. He believes that if he had not taken this action, the mistreatment would have continued.
It is important to note that while defense mechanisms serve as protective behaviors to reduce anxiety, overusing them can be problematic. Freud believed that individuals who rely too heavily on defense mechanisms may face psychological difficulties.