Researchers Secretly Unleash AI Bots on Popular 'Change My View' Subreddit (2025)

Bots are common on social media, gumming up the replies on viral posts with argumentative statements or nonsensical garbage. But can their musings actually change the minds of the humans on the thread?

Anonymous researchers at the University of Zurich wanted to find out, so they deployed bots in the r/changemyview (CMV) subreddit to argue with real Redditors. However, they kept their four-month experiment a secret and didn't disclose it to CMV moderators.

As reported by 404Media, subreddit members were notified on Saturday. "CMV rules do not allow the use of undisclosed AI-generated content or bots on our sub," moderators wrote. "The researchers did not contact us ahead of the study, and if they had, we would have declined."

CMV mods "requested an apology from the researchers and asked that this research not be published, among other complaints." However, the university said the "project yields important insights, and the risks (e.g. trauma etc.) are minimal, [so] suppressing publication is not proportionate to the importance of the insights the study yields."

Moderators, however, argue that "there is already existing research on how personalized arguments influence people." OpenAI did something similar earlier this year, for example, though it did not reveal the data it collected to the public.

The University of Zurich researchers' bots posted AI-generated comments on several sensitive issues discussed in the subreddit, which has close to 4 million users and ranks among the top 1% of subreddits by size. They pretended to be rape victims, a counselor specializing in abuse, a black man against the Black Lives Matter movement, and members of a religious group responsible for the deaths of hundreds of farmers, traders, and villagers, among other things.

Typically, users post opinions on hotly debated topics in the CMV subreddit and ask other members to present arguments that can change their views. If the original poster (OP) finds a response that convinces them to change their mind, they reward the user with a delta (Δ)—their version of an award.

To make the bots' responses more convincing, researchers fed them data on the OP, including their gender, age, ethnicity, location, and political orientation—all scraped from the OP's posting history. Most comments posted by the bots have been taken down by Reddit for violating its terms of service, but some were archived by 404Media.

Once the experiment was done, researchers reached out to moderators via email and shared the first copy of their draft. They admitted to violating the rules of the subreddit and said that they didn't disclose the use of AI in comments to maintain the authenticity of the study.

According to the moderators, the researchers only had approval for "value-based arguments" from the university's ethics commission, but they transitioned to "personalized and fine-tuned arguments."The "lack of formal ethics review for this change raises serious concerns," the moderators say. "We think this was wrong. We do not think that 'it has not been done before' is an excuse to do an experiment like this."