Basically, incomplete information means there cannot be certainty, only estimation
The greater the volume of the unknown information, the more difficult it is to make an optimal determination
It's the idea that optimal decision making in a condition of (mathematical or computational) intractability is, by definition, subjective
thus, the idea that the efforts to reconstruct are anything but interesting speculation is not mathematically supportable
(academics may use slightly different terminology, but the concept is quite basic in the field)