When people describe neutrino interactions they describe them as rare/infrequent due to the fact that the neutrinos are electrically neutral and have little mass, if any. Well why then is the photon much more strongly interactive considering that it is neutral and massless? What is the discrepancy between the two? Why is the neutrino so elusive, whereas light is so prevalent? Does this perhaps have anything to do with the fact that a neutrino is a fermion whereas a photon is a boson?
Answer
The photon does couple directly to charged stuff, e.g. via Compton scattering. This is indirectly related to the spin, as direct interactions between fermions are hard to construct.
The neutrino on the other hand does not couple immediately to any other matter particle. It requires a force-carrier. Now as it turns out the only force carriers that care about the neutrino are the $W^\pm$ (and to lesser extent the $Z^0$ boson). These are really really massive, however, making the interaction very rare.
This is a different situation than for an electron, for example. It also does not couple directly to other matter particles. Still, it can interact via the photon, which is massless and can therefore easily transmit energy and momentum.
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