Now a conceptual feeling does not refer to the actual world, in the sense that the history of this actual world has any peculiar relevance to its datum. This datum is an eternal object; and an eternal object refers only to the purely general any among undetermined actual entities. In itself an eternal object evades any selection among actualities or epochs. You cannot know what is red by merely thinking of redness. You can only find red things by adventuring amid physical experiences in this actual world. This doctrine is the ultimate ground of empiricism; namely, that eternal objects tell no tales as to their ingressions.
Thus the endeavour to understand eternal objects in complete abstraction from the actual world results in reducing them to mere undifferentiated nonentities. This is an exemplification of the categoreal principle, that the general metaphysical character of being an entity is 'to be a determinant in the becoming of actualities.' Accordingly the differentiated relevance of eternal objects to each instance of the creative process requires their conceptual realization in the primordial nature of God. He does not create eternal objects; for his nature requires them in the same degree that they require him. This is an exemplification of the coherence of the categoreal types of existence. The general relationships of eternal objects to each other, relationships of diversity and of pattern, are their relationships in God's conceptual realization. Apart from this realization, there is mere isolation indistinguishable from nonentity.
Alfred North Whitehead, Part III, Chapter IV, Section I