The quantum field theoretic picture of nature

Revisiting the many-body problem

     Reformulation:  condensed-matter physics and QFT
     But the bodies dissolve
          Quasi-particles
          Collective excitations

     Rethinking notions of fundamental particles
          Changes in ontology:  new basic constituents
          (Example:  superconductivity)
          Universality:  fundamental particles don't always matter

     The self-understanding of condensed-matter theorists