Famously, Schrödinger's cat is found to be both dead and alive within a closed system - at the mercy of quantum mechanics. But why is the cat "both dead and alive"? For the Copenhagen interpretation, according to Heisenberg "the wave-function represents a probability, but not an objective reality itself in space and time."
The conceptual construct of "dead" or "alive" is a 100% non probabilistic state (at least as conceived by an individual within his frame of reference). This 100% certainty can be seen as an 'objective reality' for the individual with that information.
If I knew that someone (that I was not observing) was driving a car and had a 50% chance of death, they would not be objectively "both alive and dead" to me, rather given the probabilities they would be "neither alive nor dead". Any positive truth statement cannot be backed up by (non-existent) observational evidence, so no positive truth statement, beyond some assumed estimate of the probabilities, is valid.
Does it make more sense to say that when a quantum system is not observable (is closed), whether a wave function or a cat, non-probabilistic conceptual statements with regards to what is inside the system will be incomplete?