Character is Destiny: Can Persona-assigned Language Models Make Personal Choices? (2025)

Abstract: Can Large Language Models (LLMs) simulate humans in making important decisions? Recent research has unveiled the potential of using LLMs to develop role-playing language agents (RPLAs), mimicking mainly the knowledge and tones of various characters. However, imitative decision-making necessitates a more nuanced understanding of personas. In this paper, we benchmark the ability of LLMs in persona-driven decision-making. Specifically, we investigate whether LLMs can predict characters’ decisions provided by the preceding stories in high-quality novels. Leveraging character analyses written by literary experts, we construct a dataset LIFECHOICE comprising 2,512 characters’ decision points from 470 books. Then, we conduct comprehensive experiments on LIFECHOICE with various LLMs and RPLA methodologies. The results demonstrate that state-of-the-art LLMs exhibit promising capabilities in this task, yet substantial room for improvement remains. Hence, we further propose the CHARMAP method, which adopts persona-based memory retrieval and significantly advances RPLAs on this task.

## introduction every man has but one destiny. with the recent advancements in large language models (llms) @xcite , role-playing language agents (rplas) have emerged as a flourishing field of ai applications and research @xcite . rplas are llm-based ai systems that simulate assigned personas, reproducing their tones, knowledge, personalities, and even decisions @xcite @xcite . they emulate various characters across extensive a. running away from the corleone family. b. avenging by stabbing the enemy and police. c. fearfully hiding in the protection of the family. d. asking for help from the government. the godfather was attacked and severely injured, lying in bed; the enemy is protected by the new york police chief; the eldest brother is irritable and the second brother is incompetent; description: michael corleone is the youngest son of vito corleone, he is known for his quiet, intelligent, and introspective nature…… memory michael joined the navy against his father's wishes. ## experiments because our inputs generally exceed 100k, it is difficult for llms to handle them directly. therefore, our approach is divided into two steps: 1) character profile construction, which includes the character's description and memories; 2) reasoning for decisions, where different llms use the constructed profile to answer the questions. ## analysis in the experiments, we wish to answer two research questions: rq1) can rplas make decisions based on historical data? rq2) what influences the decision-making of rplas?