Plato’s theory of the forms is considered to be the first famous metaphysical debate in Western philosophy. It explores the ultimate structure of reality, and questions what reality actually is, as opposed to what it appears to be. Plato came to conclude that everything in our world is only a copy of a perfect form existing in a realm attainable to us only through contemplation. However, Plato’s premise was mainly ethical, rather than metaphysical. His teacher, Socrates, in his lifetime, has turned the accepted concepts of virtue and justice on their heads to show that we do not truly know what these things are. Plato wanted to find out whether this can be known and has come to a positive conclusion using his theory of forms. He believed that philosophers are able to comprehend the ultimate form of good via their intellect and therefore what virtue and justice really are. This served as a basis for his political writing about what an ideal society would look like.
Plato saw the world as divided into two realms: the material world of appearances, which is imperfect and ever-changing and the world of ideas or “forms” which is perfect, unchanging and eternal. Plato believed that everything in our material realm is only a copy of the perfect form of that thing/concept in the perfect realm. He also noted that while the material realm is perceived through our senses, the realm of the forms can only be perceived through intellect and contemplation. Plato used the analogy of people trapped in a cave all their lives, unaware of the world outside to explain why we are unaware of the realm of the forms. He did suggest though, that we have intuitive knowledge of the forms, supposedly because our soul is of this realm and we existed in it prior to existing in our bodies.
There are two main arguments of how Plato arrived at the idea of forms. The argument for perfection suggests that we have a concept of a perfect circle, even though there are no perfect circles in nature. Plato believed this is because we have intuitive knowledge of the form of a circle that is perfect. Another argument is identifying something as the same type of thing despite differences. For example, we can say that both the sky and the sea are blue, even though they are different shades. Plato would say that we are able to identify both colours as blue because they remind us of the form of “blueness”. According to Plato it is that distant memory of forms that allows us to identify things for what they are.
It is not difficult to object to Plato’s concept. From a relativist perspective, for example, we could say that the concept of blueness exists only due to social agreement and there is nothing more to it. An empiricist would say that we identify various shades as blue because we have experience of judging them as such from an early age, and that our sense perception requires judgement. That is why people can disagree on whether the colour of the sea is blue, or in fact, green. Plato could pose a counter argument that the disagreement is only possible due to imperfection of the copy of the form of blueness or greenness. Nonetheless, because the realm of the forms is only intelligible in the mind, it is impossible to provide any factual proof.
Whatever the case, Plato’s premise was mainly ethical. He believed that there is also a form of good – the ultimate perfection, and the pinnacle of philosophical knowledge is contemplating the form of the good. Contrary to Socrates, who suggested that we can only know that we don’t really know what justice and virtue really are, Plato believed that philosophers can transcend the material world and understand the forms of virtue and justice and goodness. It is for this reason that Plato decided philosophers are the best people to rule society. He compared them to the only ones who were able to get out of the “cave” and see the world for what it is.
Plato believed that everything in the material world is only a copy of a perfect form existing in a realm of universals. He argued that it is the intuitive knowledge of the forms that enabled us to identify things for what they are. Without the existence of a form of a circle, we would not be able to imagine a perfect circle, as it is not found in nature. He also argued that it is possible to understand this realm through contemplation. He concluded that philosophers, who are able to put their intellect above their senses, are able to gain the understanding of the true form of goodness. They are, therefore, the best people to rule society in a moral and ethical way. Thus, a seemingly metaphysical argument became a great influence on moral and political ideas of Western philosophy.