Born 1896 in Switzerland died 1980. He went to school at the University of Neuchatel and the University of Zurich where he obtained his PhD and an interest in psychoanalysis. He had over 60 books and 100 articles that he wrote in his lifetime. He also had three children who he used in his studies.
Contribution to Psychology
He was the first psychologist to make a systematic study of the cognitive development. He looked mostly into the study of children. At the time the current thought was that children were just not as good of thinkers as adults because of lack of development in the brain. He found that children didn't think less then adults did it was that they had a whole different thought process. He came up with a theory called the Cognitive theory that became very popular and agreed on.