What's missing with the cat example is a measurement axis beside dead/alive. Pretend instead that we measured the cat with a different measurement that was onl

What's missing with the cat example is a measurement axis beside dead/alive. Pretend instead that we measured the cat with a different measurement that was only somewhat correlated with the cat being alive, such that this test would return "true" with a 75% chance. A subsequent second measurement using the original alive/dead criteria would now return "alive" with a 70% probability! That is, we have altered the in-between state of the cat (in the cat's favor!) by our first measurement. It is this that is unique to quantum mechanics. A pseudo-classical analogue of this phenomenon can be observed with polarizing filters. Analogous to the cat's initial radiation dose is a 45°-polarized light beam. Analogous to a measurement of the cat being alive/dead is a 0°-polarized filter – 50% of light makes it through the filter. However if a 15°-polarized filter is placed between these, one will instead observe that 70% of light makes it through the 0° filter! (You can also test this easily at home with three polarizing filters; two held at 90° to each other, and a third placed in between at 45° – the third will allow light to pass through the others.) This is solely due to the nature of electromagnetic waves, which very closely parallels that of quantum fields. Replace "light beam" with "single photon" in the above paragraph and you get a fully-quantum analogue of my modified Schrödinger's cat experiment ;)