where did he study?
He attended rural schools and determined early that his destiny was to reform education of the masses. He briefly attended Alfred University (1870), then Amherst College.
Melvil Dewey
 He attended rural schools and determined early that his destiny was to reform education of the masses.
He briefly attended Alfred University (1870),
then Amherst College,
where did the dewey decimal system come from The Dewey Decimal Classification (DDC), colloquially the Dewey Decimal System, is a proprietary library classification system first published in the United States by Melvil Dewey. when did he do so? 1876 how is the classification done? It is  formed  on the basis of the Universal Decimal Classification (UDC), which combines the basic Dewey numbers with selected punctuation marks (comma, colon, parentheses, etc.)
wiki:8307124
Melvil Dewey [SEP] Education and personal life
Dewey was born in Adams Center, New York, the fifth and last child of Joel and Eliza Greene Dewey. He attended rural schools and determined early that his destiny was to reform education of the masses. He briefly attended Alfred University (1870), then Amherst College, where he belonged to Delta Kappa Epsilon, and from which he earned a bachelor's degree in 1874 and a master's in 1877. While still a student, he founded the Library Bureau, which sold high-quality index-cards and filing-cabinets, and established the standard dimensions for catalog cards. As a young adult he advocated spelling reform; he changed his name from the usual "Melville" to "Melvil", without redundant letters, and for a time changed his surname to "Dui".