The editor of the New Atlantis writes a thought-provoking essay about what he perceives as a lack of limits in biomedical research, expressing concern for research on human-monkey chimeras, and by extension, the 14-day rule of embryo culture. Among the topics that the author takes issue with are the establishment of limits and scientific self-regulation, suggesting that society should not place too much trust on scientists to act responsibly and that strong limits should be put in place.