Whitehead's idealism on a realistic basis

Whitehead invariably described his own philosophy as 'organic philosophy' and at the same time understood it as an 'atomic theory of actuality.' Hegel's and Whitehead's philosophies are both forms of metaphysical thinking in which subjectivity is the basic structure of reality. Whitehead's actual entities realize ideas that Whitehead calls 'eternal objects.' The idealism of philosophy consists in nothing else than in the recognition that the finite is not truly an existent'. Whitehead, on the other hand, clearly regarded the concept of substance as obsolete for the philosophy of the twentieth century and characterized his system as a philosophy of finitude. The realistic basis of his idealism is expressed in the assertion that entities are actually the basic reality.