Rousseau's novel Emile or On Education is a treatise on his philosophy of education with the advocacy of developing the student’s character towards upholding naturalism in the face of the unnatural and imperfect environment of the modern society. John Dewey was a leading proponent of the American school of thought known as pragmatism, a view that rejected the dualistic epistemology and metaphysics of modern philosophy in favour of a naturalistic approach that viewed knowledge as arising from an active adaptation of the human organism to its environment. In his philosophical theory, Plato advocated an uncompromising idealism which asserted that the experiential world (empirical reality) is fundamentally unreal and the ultimate reality is constitutive of abstract universal essences of things.