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>Otherwise, we could just as correctly say that when we look at dog we are seeing the sun or the overhead florescent bulbs; that's where the photons came from

No, they didn't. The energy came from the sun, however the photons which are collected in your retina to form the image of a dog were emitted from the dog itself. "Reflection" is just the stimulation of photon emission via radiation.

https://en.wikipedia.org/wiki/Photoelectric_effect




You're gesturing at an unconvincing objection: that there is no difference between reflection and emission because there is a sense in which light passing through matter is continuously being absorbed and re-emitted. (I say "gesturing" because you don't actually know the physics; it is completely different than either stimulated emission or the photoelectric effect, which you could tell by reading the Wikipedia articles.) Explaining why this objection is boring and unconvincing would ultimately be a long discussion in the philosophy of science ("how can we keep using folk terminology that presumes a sharp devision between two concepts when a theory of physics suggests they are actually just part of a continuum?"), but you can get a sense of that by noticing that emission generally involves a change in the frequency of light while reflection does not.




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