It was great to hear that Yochiro Nambu has finally be recognized by the Nobel committee. I learnt yesterday that he is now 87 years of age, and the work that has been recognized is about five decades old. It is very hard to imagine how he did the work when there was practically no framework, and nothing to go by. The idea of spontaneous symmetry breaking which was known in palable condensed matter systems was applied in particle physics at that time! To view pions as the bosons associated with a spontaneously broken (approximate) symmetry is now something that is taken for granted. It must have been out of the world at that time.
The second half is shared by Makoto Kobayashi and Toshihide Maskawa for their work on quark mixing that predicted the existence of the third generation (5th and 6th flavours) of quarks. I believe the mathematics was straightforward, but what a leap of faith! What an audacious idea! At a time when the fourth quark was only hypothesized (and needed for consistency), to say that there should be a fifth and a sixth!