In modern philosophy Bacon stressed knowledge of the world, Descartes began with the thinking self. Hobbes reduced everything to matter, Berkeley to mind. Kant gave German philosophy its distinctive character by arguing that its prime task is the study of the process by which we form ideas. He admitted the reality of external objects, but insisted that we can never know what they objectively are, since we know them only as changed by the organs and processes of perception into our ideas.
