Idealism holds that ideas or mind are the ultimate reality. It emphasizes that knowledge is obtained through reasoning and speculation rather than observation alone. Several philosophers contributed to the development of idealism, including Plato, who believed knowledge comes from recollection of innate ideas, and Kant, who saw the mind as giving meaning to the world. Idealism views education as developing students' abilities and character to serve society by focusing on subjects of the mind through discussion and questioning.