The cave
World of senses
Shadows on the wall
Illusions
Chains
Ignorance
Fire
The sun
Objects on the wall
Physical things
The difficult ascent
The dialectic – the process of arriving at truth
The reflections
The process of understanding
The moon and stars
The Forms of justice, beauty etc.
The Sun
The Form of the Good
The effort needs to come from the individual to turn away from what they’re shown and come to the light.
Knowledge is remembering
is not strictly an argument for the Forms.
All it proves is that there are properties of things. Those properties might be immanent - in this world - or they might simply be names we give to things - this is known as nominalism.
If we have a collection of large things and their form “largeness” then we should consider the collection of things large, as well as the form “largeness” itself large.
But in that case, do we not have to appeal to a further form to consider largeness large? And why should we stop there?
This criticism undermines the idea that the Forms can be ideal standards. It shows that we would need to appeal to an infinite amount of Forms simply to make one judgement.
The name of this argument comes from the idea that if you need a Form of a man to explain a particular man, why do you not also need a third man, a Form of the Form of the man to explain that?
There is a lack of empirical support.
It is not really surprising that Plato provides little empirical evidence for his theory as he shows, especially in the analogy of the cave, that he believes empirical data is next to useless in gaining real knowledge.
Plato is a rationalist and, as such, makes use of logic and a priori reasoning for his proofs.
From a modern standpoint, it looks suspicious that the theory has so little grounding in empirical data, and indeed, appears completely counter-intuitive.
For instance, if this world is not really real, and the World of Forms is invisible and only knowable through the intellect, how is it that we are able to predict the behaviour of this world so well through scientific theories? And not just predict, but also manipulate and make the natural world work for us through the use of technology?
Plato was not able to see the astounding success of science, which would come nearly 1800 years after his death.
However, it is possible that even if he could have foreseen it, he might still have pointed to the prisoners making guesses about the objects that threw their shadows on the wall in his cave analogy and implied that science is still just a really sophisticated version of this game.