I really admire Jean William Fritz Piaget (1896 - 1980).

He was an epistemologist and a psychologist, creator of genetic epistemology. He is famous for his contributions in the field of genetic epistemology, for their childhood studies and for his theory of cognitive development and intelligence. Piaget was born in 1896 in Neuchatel, in the Francophone region of Switzerland.

Piaget was a precocious child who developed an interes in biology and the natural world. He was educated at the university of Neuchatel, and studied briefly at the University of Zurich. Piaget moved from Switzerland to Paris, after his graduation and he taught at the Grange-Aux-Belles Street School for Boys. The school was run by Alfred Binet and he stated that intelligence developement so Piaget assisted in the making of Binet's intelligence tests. It was while he was helping to mark some of these tests that Piaget noticed that young children cosistently gave wrong answers to certain questions. Piaget did not focus so much on tha fact of the children's answers being wrong, but that young children cosistently made types of mistakes that older children and adults did not. This led him to the theory that young children's cognitive processes are inherently different from those of adults. In 1923, he married Valentine Chanetay and they had three children, whom Piaget studied from infancy. From 1925 to 1929 he was professor of psychology, sociology and the philosophy of science at the University of Neuchatel. 

In his logical model of intellectual development he mention that intelligence develops in a series of stages that are related to age and are progressive because one stage must be accumplished before the next can occur. For each stage of development the childs forms a view of reality for that age period.

Next, the child must keep up with earlier level of mental abilities to reconstruct concepts. He defined this as an "spiral of concepts".

I admire Piaget because he created a new conception of education, which was very important and is important today too.