Plato theorized that a transcendent World of Ideas contained the perfect
Forms of every object on Earth. When we see a table in our physical world, it is an imperfect copy of the Form of a table. To illustrate this, Plato used the “Allegory of the Cave.”
A group of humans are imprisoned in a cave. Behind them blazes a fire that casts shadowy objects onto the wall in front of them while hiding the true Forms of the objects themselves. These illusions represent our fallible human senses, but Plato believed that our knowledge of Perfect Forms was also innate to us. It was only through reason that we could unlock this true knowledge.
Plato believed that this contrast between the Ideal Forms and our imperfect copies also applied to concepts such as Goodness and Justice. Plato suggested that using reason to reveal the perfect Form of Goodness, instead of our imperfect copy, was
the ultimate purpose of philosophy.