It could merely be that the scientist knows that his research in particular is being watched by men who will immediately misuse it when they can; allowing some random person to re-run the experiment is not a problem, assuming that the random person is not being watched in particular.
It could be that the experimental work is complex enough, and the expected returns unexpected enough, that the scientist has good reason to think that it will be a decade or more until the experiment is re-done—by which point one may hope that the political/social landscape may have changed enough to put less emphasis on evil uses (e.g. a major war may have ended in the interim). (Note that, in the case of one particular theory—continental drift—it was suggested under that name as far back as 1912 - and the idea of the continents moving was proposed as early as 1596 - but was still not accepted in the 1940s).
These assumptions are both a good deal weaker than the one you suggest, but I don’t think they’re unreasonable.
It could merely be that the scientist knows that his research in particular is being watched by men who will immediately misuse it when they can; allowing some random person to re-run the experiment is not a problem, assuming that the random person is not being watched in particular.
It could be that the experimental work is complex enough, and the expected returns unexpected enough, that the scientist has good reason to think that it will be a decade or more until the experiment is re-done—by which point one may hope that the political/social landscape may have changed enough to put less emphasis on evil uses (e.g. a major war may have ended in the interim). (Note that, in the case of one particular theory—continental drift—it was suggested under that name as far back as 1912 - and the idea of the continents moving was proposed as early as 1596 - but was still not accepted in the 1940s).
These assumptions are both a good deal weaker than the one you suggest, but I don’t think they’re unreasonable.