RAZD writes:
If you don't have a means to detect presence then you cannot test for when it is absent.
If the thing in question is empirically detectable then there is no reason in principle why it's presence cannot be tested for is there?
If the thing is question is not empirically detectable then any conception of it
must be derived from the internal workings of the human mind. How could it possibly be otherwise?
RAZD writes:
Do you have a means to test for the presence of supernatural essences?
If they are empirically detectable - Yes.
Otherwise - No.