Being a research subject

The Declaration of Helsinki is written from end to end around human subjects, their informed consent, their right to withdraw at any moment without justification, and the duty to place their interests above those of science. Simulation has taken a large part of the work that used to require them. Models predict toxicity, virtual cohorts stand in for control arms, and regulators now accept some of that evidence in place of animal studies. What the simulation cannot supply is the thing the declaration protects, which is a body that will carry the result and a person who agreed to it knowing they might be harmed. Digital twins are not subjects. They are hypotheses, and no committee has ever been asked to protect one.