His love of mathematics and physics lead Plato to believe that under the seeming chaos and disorder of the world around us, there must be an order. This idea of 'method to the madness' was reflected in Plato's belief that all of the Forms are linked together. The highest of them is the 'Form of the Good'. It is from this supreme Form that all the others derive. For Plato, the ultimate aspiration for a creature, and most certainly for a human being, was to pierce the surface of our reality, and acquire 'true knowledge', that is knowledge of the Forms and in particular, the Form of the Good.
To clarify and simplify his theory, Plato came up with the analogy of the prisoners in the cave. He told the following story: Some prisoners have been chained up in a cave since birth. They are linked together facing a wall, with their necks firmly held in place, so that they cannot turn their heads. The only thing that they have ever known is what they have seen on the cave wall in front of them. Behind the prisoners is a bright fire, and between them and the fire is a walkway, stretching the full length if the cave. Along this path, the jailers move, carrying objects and going about their daily routine. The light from the fire casts shadows on the wall in front of the captives, and it is these shadows which the prisoners take to be reality. However, one day a prisoner escapes. For the first time in his life he turns away from the wall and sees the fire. It is painful to him, and the light from the fire blinds and frightens him. Once he has adjusted to his surroundings, he dares to venture outside the cave; he looks up at the sky and sees the sun. Again, he is dazzled by the light and cannot believe his eyes. Soon, however, the prisoner realises that there is another world outside the cave, and that everything he has taken, as reality was a lie. He wants to share his amazing discoveries with his companions, so that they too might free themselves from the shackles of the cave and discover the real world. However, upon his return to the cave, his friends think that the 'enlightened' prisoner has lost his mind, and refuse to listen to his wild and fantastical tales.
So, how did Plato intend his listeners to interpret this analogy? Each part of the story represents part of Plato's philosophy. He suggests that we are like the prisoners chained to the wall. Our 'reality' is the cave wall, and the flickering shadows are the objects, which we see in the world around us. In actual fact, these objects are not real. Like the shadows, they are imperfect reflections of the Forms (in the analogy, the Forms were represented by the jailers and the items which they carried across the walkway). Plato was trying to show us that what we consider to be real is nothing more than shadow, crude and without detail.
The prisoner who escaped represents the philosopher, to Plato's mind, the only person who can find true knowledge through reflection and contemplation of the Forms. He is the only one who dares to turn away from the wall into the unknown. The philosopher discovers the truth, yet his friends will not accept his incredible ideas, because our world does indeed seem real, and it is far simpler to believe our senses. The sun represents the Form of the Good from which all the other Forms receive their perfection and very existence, much in the same way that everything in our world ultimately owes its existence to the sun.
In conclusion, Plato came up with his analogy to explain his ideas, which he did by using each part of the story to represent part of his theory. As I have mentioned, the shadows are symbolic of the objects we take as real in our world. However, by making these objects shadows, Plato illustrates his belief that they are not real. They are just imperfect silhouettes or outlines of something greater and more perfect, which we cannot see: they are reflections of the Forms.
2) On what grounds might Plato's understanding of human reasoning be criticised?
As with every philosophical theory, Plato's Theory of Forms can be questioned and disputed, because there is no evidence to prove its verity. Plato acknowledged the criticisms of his contemporaries, yet he refused to accept or even consider them, remaining steadfast in his conviction that he had discovered the ultimate truth about human reality and existence. He saw himself as the escaped prisoner from his analogy of the cave, ridiculed and scorned by his fellows after relating his amazing discoveries of the outside world. Plato believed other people, and particularly non-philosophers, to be like these ignorant prisoners, too weak and frightened to turn their heads away from the wall to his perfect, eternal realm beyond he shadows. But could the other realm really be as heavenly and wonderful as Plato would have us believe? Surely, if there is a Form of everything in our world, then the answer is a definite 'no', because there are plenty of disgusting, unpleasant things on earth. This argument constitutes one of the main criticisms of Plato's theory. If everything is a replica of its perfect from, then is there a perfect Form of dog mess? According to Plato, there must be, and yet, it seems to undermine his idea of the Forms being flawless and perfect. This presents a problem, because either Plato accepts that there are perfect Forms of repulsive things (something which he was not keen on doing) or he admits that his theory of Forms is useless. If we deny the existence of some or one of the Forms, then the whole theory collapses. After all, not even Plato himself would defend the argument which claimed that 'everything we see in the world around us is false, with a few exceptions...'
Another criticism of Plato's ideas is known as 'The Third Man Argument'. This argument uses Plato's own logic, to disprove his theory. The Third man Argument states that if everything is derived from a Form, then the number of Forms must be infinite. There can be no one single Form of anything. The reasoning behind the claim is as follows: If I have a group of cats, they form one group, or type of thing. All the cats derive from the Perfect Form of Cat, so now, I have all the cats, plus the Form of cat. The addition of the Form has suddenly created a whole new group. I now suddenly need a new Form to explain the existence of my new group. Once I have added the second Form of Cat, I am once again presented with a new group. There must be a third Form of Cat, and a fourth, and so on. The Third Man Argument applies again and again, without end, and this idea in itself is absurd. Although in reality, this criticism amounts to little more than a game of numbers, it is relevant in that if we deny that there are an infinite number of Forms (as Plato surely would) then we must accept that there are no original Forms, because as I have demonstrated in the cat example, one Form must automatically create another and another. Plato's very own reasoning states that this must be the case, so we find that effectively, the logic which he so loved has thwarted him!
In his lifetime, Plato took a rather elitist attitude towards democracy, believing that it gave power to the majority, whether their ideas and actions be good or bad. He saw the average man as too ignorant to see our 'reality' for what it really is. How can people who live in the shadows of such ignorance ever be trusted to make decisions which are morally correct? Plato felt that only the philosopher, who spent his time gaining true knowledge in reflection and contemplation of the Forms, could really distinguish what is wrong from what is right, and act accordingly. He also said that knowledge is virtue, so nobody would ever consciously do wrong or behave immorally. This is based on the Socratic idea that nobody voluntarily chooses what is bad for them self. They are simply blinded by their own ignorance. However, there is a considerable error in Plato's estimation of human nature. For example, people who smoke know it is wrong, and potentially fatal, yet they will continue to do it. Therefore, knowledge does not automatically lead to knowledge, and this undermines Plato's whole morally theory, which rests on the assumption that it does. Similarly, Plato instantly assumes that we will understand all the particulars of his complex and rather incredulous theory. However, how can an individual really know when they have finally reached a correct understanding of virtue, and the nature of goodness? When can we definitely say that we have emerged from the cave of shadows and ignorance, into the bright light of truth?
Plato was most certainly a rationalist. He believed that the only way we gain knowledge of the world around us is through reasoning and logical contemplation of the Forms. The opposing view comes from an empiricist's opinion. Empiricists believe that we gain knowledge through experience, and the way our senses interpret situations. They would argue that because Plato's reality cannot be experienced or recognized through the human senses, it couldn't exist. There is no real evidence to support Plato's heavenly realm, we cannot see it or feel it, so how can it be real?
The realm of the Forms seems to be a fairly hazy concept to the average person, as well as quite a difficult one to interpret, particularly as Plato's dialogues do not go into much detail about it. A man called William of Ockham devised a theory, which stated that if we are presented with two explanations of the same phenomenon, both equally supported by evidence, we will almost certainly choose to believe the simplest one. It stands to reason that we would rather trust our senses, which we can actually feel, than an unnatural realm of Forms, which seems incomprehensible to us, as we will never be able to experience it.
To conclude, there have been many criticisms of Plato's theory of Forms over the years. Each claims that they can disprove Plato's ideas, which were certainly not one hundred percent foolproof or infallible in the first instance. Much of Plato's theory is unclear, for example, if it is found outside of our time and space, then where exactly is the realm of the forms? What does it look like, and more importantly, what do the Forms really look like? Considering this, it is hardly surprising that Plato's ideas have been hotly contested and criticised by his contemporaries as well as the philosophers who have studies his works over the centuries.