W. T. Stace, in his essay, “Greek Idealism and Hegel,” (Chapter 1; The Philosophy of Hegel: A Systematic Exposition), says that the universal philosophy “is not simply the philosophy of Plato, nor yet simply the philosophy of Aristotle. The systems of these men are but special presentations of the one universal philosophy, special forms which it assumed in their hands, in the particular age and circumstances in which they lived. It is to be found in them as the inner essence of their thought. It is what they held in common, to which each added special points of view of his own. This underlying substance will be the substance of Hegel also.”
Stace begins his discussion of Greek idealism with a survey of the philosophy of Eleatics and the likes of Protagoras who have made contributions to the universal philosophy. But much of his essay is devoted to Plato and Aristotle. From his discussion of Greek idealism, Stace develops the following list of the essentials of this universal philosophy:
I. The real is what has a wholly independent being, a being dependent only on itself.
II. Appearance is what depends for its being upon another being. This other being is the real.
III. Existence is what can be immediately presented to consciousness. It may be either a material or a psychic entity.
IV. The real is the universal.
V. The real is not an existence. Its being is logical being.
VI. Existence is appearance.
VII. The real, that is, the universal, is also thought, mind, or intelligence ; but this thought, mind, or intelligence is not an existent, individual, subjective mind, but an abstract, universal, objective mind. It has a logical and not a factual being.
VIII. The real, that is, objective thought, is the first principle or ultimate being, the Absolute, which is the source of all things, and from which the universe must be explained.
IX. This first principle is first only in the sense that it holds logical priority over all things. It is not first in order of time.Stace appears convinced that the philosophy of Hegel can be seen as the accumulated wisdom of mankind. In the final paragraph of his essay, he says:
The philosophy of Hegel, it will be seen, is not something simply invented out of nothing by himself and flung at random into an astonished world. It is no crazy fancy of an individual's brain, no gimcrack novelty. It is not the pet theory of some erratic genius, nor is it merely one theory among many rivals. The true author of it is, not so much Hegel, as the toiling and thinking human spirit, the universal spirit of humanity getting itself uttered through this individual. It is the work of the ages. It has its roots deep in the past.Along with Greek idealism, Hegel was also heavily influenced by the critical philosophy of Immanuel Kant. It is clear that the fundamental principles of Hegel are closely linked to the fundamental principles of the Greeks and Kant.