Education theoreticians developed mediation theory for many years to emphasize society's responsibility towards the success of learning among all children, says Flavian, though they usually did not use the term mediation. From the several 20th-century learning theories, she has chosen five who approach learning from different perspectives at different times and in different cultures, and shows how mediation links them. The theorists are John Dewey (1859-1952), Jean Piaget (1861-1980), Lev Vygotsky (1896-1934), Reuven Feuerstein (1921-2014), and Howard Earl Gardner (1943-).