> a huge surplus of nonsense in the theory It gets even worse if one starts thinking about the flashlight's filament or semiconductor, the wall, stratified Jup

> a huge surplus of nonsense in the theory It gets even worse if one starts thinking about the flashlight's filament or semiconductor, the wall, stratified Jupiter with its optical depth, the flashlight-wielder's visual system, and everything in between all being (sets of) quantum objects. Maybe the thing to do in this example is to assume correspondence and think classically, and insist on using a fewer-quantum-number example if one wants to think quantumly. However I tend to admire detailed wrestling with everything-is-quantum in an example like this. Maybe start by remembering that the spot-on-wall-to-retina is relevant, not just the flashlight-to-wall.