The classical soliton solution is defined to be one that (1) has finite and nonzero rest mass, and (2) is contained in a finite region in space. Starting with a relativistic boson field with nonlinear coupling, four dimensional quantum soliton solutions are discussed by considering the classical solution and then quantizing it by a general canonical procedure. Remarks are then given on the generalization of the soliton mechanism to include fermions, leading to abnormal nuclear states. (SDF)