A survey of materials science through our experiences shows that our knowledge of amorphous solids is quite poor compared
with that of crystalline solids. Most pure substances can be obtained, in principle, as crystalline as well as non-crystalline
states by physical and chemical methods. Destruction of the three-dimensional periodicity in crystalline substances will produce
novel properties which cannot be anticipated from knowledge of crystal sciences. One direction of materials science in the
coming century will surely be a new realm of amorphous condensed matter science.