Murray Gell-Mann: I find that particular aspect frustrating. It’s nice to be credited with quarks, and have the Swedish foundation refer to my work in awarding the prize to these three wonderful experimentalists who confirmed the existence of quarks inside the proton. I was delighted with all of that. But I was not delighted with this funny interpretation. Actually, the Nobel Foundation didn’t say it, didn’t actually state the thing wrong. But the implication was that by calling them mathematical, I was sort of denying their existence. What I meant by mathematical was that they wouldn’t come out and be seen individually and directly in the laboratory. And that’s turned out to be so; they are permanently trapped inside. We didn’t understand, of course, back in 1963. I didn’t understand why they were permanently trapped. But it was later on, when we formulated the dynamical theory, quantum chromodynamics, that we began to realize what was going on.