This comes near the truth. But the physical and formal, as he understands them, cannot be equally real with the psychical, on his own showing. They are the appearances which rise within the psychical. They are derivations from the real, but not self-supporting realities. Otherwise we would have three Irreducibles, three Absolutes, three Self-Existences.
Science cavils satirically at the theological dualism of a good and an evil principle in nature.
In some guise or other, every real thinker must sooner or later stumble upon these realities in nature. When this happens, art and religion and science degenerate into sentimentalism. One of the most important tasks of philosophy is to clearly define the nature of the psychical, locate its place in the scheme of things, and keep it in that place. In this connection it is to be remembered that the determinate character of mind is as completely conditioned by physical and formal principles, as is the determinate character of a chemical element.