In order to understand Plato’s concept of the Form of Good, let us at first refer to the original Theory of Forms. The ethical problem it was developed to solve was: how can human beings live a satisfying, happy life in a conditional, altering world where everything they connect themselves to can be taken away any minute? How can the world seem to be both enduring and shifting simultaneously? Plato concentrated on the concept of two dimensions of reality: the world we recognize through the senses which appears to be always changing; the world that we identify through the mind, with the use our perceptions, which appears to be permanent and unchanging. So which is most genuine and why does it happen to be both ways?

Plato divides existence into two spheres: the material sphere and the transcendent sphere of forms. According to Plato’s theory of the segments of the human soul, an individual has access to the realm of forms through the mind and reason. This gives humans admission to stable world, secure from the pains and transformations of the material world. Searching for a solution for the first ethical problem, Plato proposed that by cutting ourselves from the material world and our body and building up ability to consider the forms, we may discover a value which is not subjected to alteration or collapse. The philosopher also makes attempt to solve the problem of permanence and change, defining the most real world of two by splitting existence up into two realms. We distinguish a different world, with dissimilar objects, through our mind than we do through the senses. While the sense-perceived material world is constantly altering, the one perceived by mind is permanent and incontrovertible. Therefore, the second world is more real, since the world of change is purely a defective representation of this world.
According to Plato, a form is an abstract property or quality. The forms are transcendent (do not exist in space and time); pure (pure properties alienated from all other properties); systematically interconnected (embrace a system leading down from the form of the Good, progressing from more wide-ranging to more specific, from more objective to more subjective); ultimately real (not material objects, which are reproductions or descriptions of some set of forms). The forms are also represented as archetypes, that is, they are ideal patterns of the property that they represent. The forms are the causes of all things, since they offer the clarification of why everything is the way it is, and they also are the source or basis of the existence of all things.

The six main properties of the forms are Form of Good, Higher Forms, Lower Forms, Material Objects, Images, of which Form of Good is the most general, abstract, and objective one. Plato uses the sun metaphor to clarify how the forms in general, and the form of the Good specifically, are operating as causes of all being in the mentioned two ways. Just as the sun, “whose light makes our sight see in the finest way and the seen things seen” (The Republic 188), provides light which permits us to observe objects, the form of the Good gives order and clearness to allow us to identify objects: “eyes, when one no longer turns them to those things over whose colors the light of day extends but to those over which the gleams of night extend, are dimmed and appear nearly blind as though pure sight were not in them, when one turns them on those things illuminated by the sun, they see clearly and sight shows itself to be in these same eyes.” (The Republic 188)

The sun also generates the energy for the sustenance and growth of all living things, and so does the form of the Good providing the arranged system and organization which is the foundation of the existence of all things.