 It is also worth noting that an objection against individual continuity in dualism can be deployed against individual continuity in materialism. One objection (that can be traced back to Kant) against dualism is that the dualist is unable to account for the possibility that the soul or immaterial self is constantly being replaced by different individual selves, (with complete updated “memories” and psychological qualities) thus creating the illusion of personal continuity of the self-same subject. If the self is immaterial, how would we notice the successive changes? This may be called the problem of undetected (and perhaps undetectable) soul-switching. This objection faces many obstacles, one being that we would be unable to properly account for our experience of successive states (we hear Big Ben ring three times by first hearing it ring twice) if we are not the self-same individuals over time. But more to the point, in terms of continuity, it is logically possible that material bodies are switched every nanosecond. If the switch (or annihilation and creation) were done in an instant (as opposed to an interval) there would be no duration, no event that could be measured by us that would reveal the switch. If undetectable material object-switching is not a problem, then undetectable soul-switching should not be a problem.