  Ettore Majorana contributed several ideas that have had significant, lasting
impact in condensed matter physics, broadly construed. Here I will discuss,
from a modern perspective, four important topics that have deep roots in
Majorana's work: 1. Spin Response and Universal Connection; 2. Level Crossing
and Generalized Laplace Transform; 3. Majorana Fermions, From Neutrinos to
Electrons; 4. Majorinos and Emergent Symmetry.
