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.
Ulric Neisser
Ulric Gustav Neisser (December 8, 1928 – February 17, 2012) was a German-born American psychologist and member of the US National Academy of Sciences. He has been referred to as the "father of cognitive psychology." Neisser researched and wrote about perception and memory. He posited that a person's mental processes could be measured and subsequently analyzed. In 1967, Neisser published "Cognitive Psychology", which he later said was considered an attack on behaviorist psychological paradigms. "Cognitive Psychology" brought Neisser instant fame and recognition in the field of psychology. While "Cognitive Psychology" was considered unconventional, it was Neisser's "Cognition and Reality" that contained some of his most controversial ideas. A main theme in "Cognition and Reality" is Neisser's advocacy for experiments on perception occurring in natural ("ecologically valid") settings. Neisser postulated that memory is, largely, reconstructed and not a snap shot of the moment. Neisser illustrated this during one of his highly publicized studies on people's memories of the Challenger explosion. In his later career, he summed up current research on human intelligence and edited the first major scholarly monograph on the Flynn effect. A "Review of General Psychology" survey, published in 2002, ranked Neisser as the 32nd most cited psychologist of the 20th century.