Non-interference
Non-interference is a formal security property, given its precise form by Joseph Goguen and Jose Meseguer in 1982: one group's actions have no effect on what another group can see. If the difference can be seen at all, the property fails. It has been proved for systems that keep their parts strictly separate, such as the seL4 microkernel, under stated assumptions. A useful AI agent breaks it by design, because what the agent does depends on what it read.
