Plato said nothing is perfect but unchangeable ideas that we inherit in our souls. He meant that every object such as trees, dogs, horses, chairs, books etc have a perfect form within the universe and what we grasp is only a shadow of that perfect form and that we are all born with the world of forms in our minds even if we don’t know it. He says that we have this idea and until we reach the truth the soul will keep being reincarnated until the soul reaches a state of enlightenment.
Then the soul can rest.
Plato also had a different idea to Heraclitus, he believed that there is a certain truth but the material world cannot reveal it. For example this is how I interpret his idea. There may be something that’s happening but know one knows of, but it is still happening. It is the truth that there are a certain number of species in the world but we cannot count every species of sea creatures because it is ever-changing, we can estimate how many, but there will always be a true number that we cannot know. There will be a certain number of creatures that is the true number but we cannot know in this world but the truth does exist. Plato thinks that the truth is to be found elsewhere on a different plane. It can only present appearances which lead us to form opinions rather than knowledge.
Socrates asked, ‘What is justice’, and, ‘What is beauty’, he wasn’t seeking a definition of these words he was looking deeper and trying to find out the essence of these qualities. Plato believed they had a sort of universal existence, a reality of their own. When we see examples of justice in the world, we recognise them as such because we see that they reflect the nature of true justice or the form of justice. When we call something beautiful, it is because we have an innate knowledge of true beauty or the form of beauty. We just know it’s beautiful, but everyone has different opinions. Our ideas of justice or beauty are imperfect, we have never witnessed true justice or true beauty but we just know what they are, because knowledge is a kind of recollection. We have an instinctive knowledge of the forms which we are born with. We may say a negative point about someone’s look and know they aren’t beautiful which we understand as a concept even though we have never seen a perfect example of it.
Plato believed that we all have concepts of the ideal forms without having experienced them, our souls must have known the forms before we where born, therefore he goes on to say that people must have immortal souls.
Plato argued when we use words for different objects, we think of the ideal forms. So cat is an ideal form with the name cat. If our parent told us a different word for cats we would still think of the ideal forms but associate it with the word we have been taught. The world is just how we talk about the object, how we tell it to someone. But when we are babies we don’t think cat, we know the ideal form of a cat, but we focus on the image of the ideal form to link all cats together but the word is not built within us, it is passed from generation to generation. The words we use for cat, dog, and horse are not just for each individual cat but a universal word for all cats, therefore when you think of a cat you think of the shape of a cat, tail, eyes ears and we think of the ideal form of a cat. Plato said that the ideal cat that you think of associated with cat in general must have been created by God. He believes cats that we see everyday are inferior and they are imperfect copies of the ideal form of a cat, because they are ever changing and are individual. But the ideal cat is eternal, depending on nothing for its existence, and it is the object of knowledge, not opinion.
Plato was also a mathematician. Another way to understand the theory of forms is by considering them in terms of mathematics. For example a two dimensional circle is made up by a series of points which make a curved line in the shape of a circle. No-one has seen a perfect circle, not even if they have drawn what they think is a perfect circle using special computerised equipment, because the circles are all different sizes and thicknesses. But we have an idea, when we think of circle, the idea of a perfect circle. The form of a circle has never been seen, you have seen many imperfect copies but not the actual form. People do know what a circle is, they can define it but at the same time realise that it cannot be translated into the material world we live in without loosing its perfection. The form of a circle exists, but not in the physical world of space and time, its unchangeable image exists in the world of forms, but can only be known by reason. Forms have greater reality than objects in the physical world because they are models and are perfect and unchanging. As ideals, they make physical objects seem real because they resemble the forms, just as the shadows in the Allegory of the Cave, which only had a kind of existence because they resembled the physical objects. Circularity, squareness and triangularity are good examples of what Plato meant by forms.
Plato believed the forms where interconnected and that they where all arranged in a hierarchy. The top most important form is the form of the good. Just like the sun in the allegory of the cave, the good illuminates the other forms. And we have never witnessed with our senses an example of perfect goodness. In the end, real knowledge becomes a knowledge of goodness.
In the end Plato concluded there must be two worlds. One where we experience and sense, this is also called the empirical world. Nothing ever stays the same within this world, and we only see shadows of the truth and poor copies of the forms. This world is less real than the world of forms, because the forms are immutable and eternal and are the proper objects of knowledge.