I'm a high school student reading through a book on the discovery of the Higgs boson, and, among several other things, there's one part that I don't understand completely. I understand that the Higgs field is what gives mass to lots of particles that would otherwise be the same without the Higgs breaking their symmetry, and I also understand that particles like protons and neutrons aren't massive just because of the Higgs. The explanation that the book offers is that the mass of a neutron is caused by the kinetic energy of the constituent quarks held together by the strong interaction. That much makes sense to me, but why wouldn't neutrons in a nucleus have higher mass? They're bound to protons by the strong interaction as well, and that interaction holds a lot of energy that we've used to make bombs and power plants and stuff. Are neutrons that are 'alone' lighter than neutrons next to protons? Sorry if this is a question that's been covered before. I tried a lot of different ways to search my question but didn't get the answer I was looking for. Thanks!