Sam asked:

What could be the explanation of epistemology using Plato’s allegory of the cave?

Answer by Graham Hackett

Plato must have been an excellent teacher. Many people might dislike his use of the technique of dialogue and metaphor, and they would no doubt have preferred him to write text books, or straightforward academic papers. But there is no quarrelling with the tension and drama he creates with his particular methods. I have often imagined him holding a group of his students rapt, as he drew out the lessons from the cave metaphor, perhaps drawing a diagram of the cave and its occupants in the sand, using his staff. I have been a lecturer myself, and often wished I could have devised teaching metaphors as vivid.

Many teachers of philosophy since Plato have used and elaborated on the cave metaphor, sometimes adding details (why not? Metaphor is a very flexible technique) and sometime paring the image down a little. The main details are always;

• A cave with just one small entrance

• A group of people who could be actual slaves, or who could be slaves in the sense that they are in thrall to false data masquerading as knowledge

• The ‘slaves’ sit with their backs to the entrance, watching the wall before them

• There is a fire at the entrance to the cave

• People passing between the fire and the cave entrance are shadow on the back wall of the cave.

• The slaves believe that these shadow images represent reality, and have no direct apprehension of the objects causing the shadows

Think of the metaphor first, as offering Plato’s opinion on the various sources of knowledge, perception, testimony, memory, reason and introspection. What the inhabitants of the cave apprehend consists just of shadow images. The objects which are casting these shadows are outside the cave and, if they partake of reality at all, are just a pale imitation of it. The shadows in the cave are not knowledge in the way that many people today consider it; as justified true belief. If the slaves could turn round, or better still, leave the cave, they would, (after becoming attuned to the bright light), see that what they have taking for reality is just an illusion, and the real objects are outside the cave. The shadows on the cave wall are the objects of perception, and as long we take them at face value, can never provide us with true knowledge. The only way we can acquire true knowledge is by seeing what is causing the shadows.

To do this, Plato tells us that we must abandon our total trust in perceptual knowledge and use our reason. Only by using reason can we acquire knowledge of what is outside the cave. In Plato’s own language in the theory of forms, we need to apprehend the true ‘form’ of knowledge, rather than the pale perceptual copies of it. If you wish to add more metaphor still, you can think of ‘a veil of perception’ between the inhabitants of the cave and what lies outside, preventing them from getting to know the real truth. You could argue that the power of Plato’s metaphor breaks down a little here, as you could just argue that the clueless cave dwellers could just get up, turn around and leave the cave. Job done! This is true knowledge! However, the metaphor can still be argued for by saying that this is not an option for any of us; we cannot come out of the cave, peer through the veil of perception, or even turn round. Our only hope is to use our reason to try and gain an insight about what lies outside our dark, damp smelly cave.

Another image I have of Plato teaching, is to visualise him using his cave metaphor to give a lesson in how we might change from being a shadow-fixated slave to becoming a free person, strolling in the sun-bright, knowledge-rich area outside the cave. The path from perceptual delusion to true knowledge is not easy. One of the slaves is gradually introduced to the outside world, not without some kicking and screaming apparently. The slave is only taken from the cave very gradually and is very reluctant to leave the apparent (but illusory) certainties of his habitat. He is blinded by the light, and takes a long time to get used to it, but after doing so, begins to apprehend things as they are. The real form of knowledge is at last acquired. This part of the cave metaphor is to demonstrate that there is a very long educational process needed before our slave of perception can gaze at the sun of reason. Not every one of the slaves will be able to benefit from such an education, and the process is long and arduous.

Finally, the enlightened sage will reluctantly return to the cave, to live with, and share the problems of the cave dwellers. The newly enlightened one, in attempting to enlighten the others will often meet with opposition and sometimes outward derision. Clearly, even the trustworthy testimony of a philosopher as to the nature of truth could be regarded with suspicion.

I do not think I have exhausted the possible lessons which could be drawn from the analogy of the cave, but the above is at least a start.