Good questions.<p>* One thing that can stop them is the law; it could be made illegal, which does stop a lot of behavior. International treaties often work too.<p>* Also, if it&#x27;s considered out-of-bounds by the scientific community then it could ruin the scientists&#x27; career; that&#x27;s probably not a risk that a talented scientist with a promising career would take. They couldn&#x27;t even publish a paper, publish in arXiv, get feedback on their work, or participate in any online discussion. They couldn&#x27;t go to a conference (there wouldn&#x27;t be one in their field) or even tell anyone what they are working on. What a life to choose.<p>* Significant progress likely requires more resources than could be mustered covertly, including financial, technological (where do you buy equipment and supplies?), and especially labor: Not only do they need talented PhD students and postdocs, but progress in most fields requires a whole community of scientists who build on each other&#x27;s work, not one who discovers it all themself.