Gustav Fechner
Fechner, along with Wilhelm Wundt and Hermann von Helmholtz, is recognized as one of the founders of modern experimental psychology. His clearest contribution was the demonstration that because the mind was susceptible to measurement and mathematical treatment, psychology had the potential to become a quantified science. Theorists such as Immanuel Kant had long stated that this was impossible, and that therefore, a science of psychology was also impossible.
Morton Deutsch
Morton Deutsch (February 4, 1920 – March 13, 2017) was an American social psychologist and researcher in conflict resolution. Deutsch was one of the founding fathers of the field of conflict resolution. A "Review of General Psychology" survey, published in 2002, ranked Deutsch as the 63rd most cited psychologist of the 20th century.