John Dewey (1859-1952) was an American philosopher, psychologist and reformer of the American education system. During his long life, he wrote many books and advocated the philosophy of pragmatism, which is based on the idea that the best measure of truth is usefulness. Dewey’s theory is also called instrumentalism. During his life he continually stressed the importance of learning being considered a social interaction and the school as a social institution, and also highlighted the importance of students taking an active role in their own learning.