Tuesday, June 16, 2015





Most people think that knowledge is pretty important. They spend their time scouring the web for news stories, reading books or journals, and paying money to go to school to learn. The underlying assumption in this pursuit is that people think that what they are assimilating is true. Notwithstanding those addicted to fiction, few would spend money or time memorizing what is entirely false.

When asking professionals, most philosophers in the university today, what knowledge is, they’ll explain that knowledge is justified true belief.  This is allegedly given them by Plato from his book Theaetetus. Keep in mind that in this explanation there are three parts to knowledge.

  1. The first is the justification.  Justification is the reason or account given for the belief.
  2. The second is truth. Truth here is correspondence to reality.
  3. The third is belief. Belief is simply the view or judgment that is held.

Overlooked in this explanation of knowledge is Socrates’ critique of this ‘definition’ in Theaetetus.  The relevant parts from the text are found at the end of Socrates dialogue with Theaetetus (209e-210a):

Socrates: Well, if ‘adding an account’ means that we are required to get to know the differentness, not merely judge it, this most splendid of our accounts of knowledge turns out to be a very amusing affair. For getting to know of course is acquiring knowledge, isn’t it?

               Theaetetus: Yes.

Socrates: So, it seems, the answer to the question ‘What is knowledge?’ will be ‘Correct judgment accompanied by knowledge of the differentness’- for this is what we are asked to understand by the addition of an account.’

Theaetetus: Apparently so.

Socrates: And it is surely just silly to tell us, when we are trying to discover what knowledge is, that it is correct judgment accompanied by knowledge, whether of differentness or of anything else? And so, Theaetetus, knowledge is neither perception, nor true judgment, nor an account added to true judgment. [emphasis mine]

Theaetetus: It seems not.  

The problem that Socrates points out is that justified true belief as knowledge sneaks in justification as a kind of knowledge to shore up knowledge. This is surely circular.

Another problem, which is not mentioned, is that if justification is knowledge, then that justification also needs a justification, which needs a justification, all the way to an infinite number of justifications for the justifications. This infinite regress shows no hope of hitting a foundation for knowledge. Without any foundation, the infinite regress shows that justified true belief is not an adequate definition for knowledge.

In sum, there are two problems with using justified true belief as the definition for knowledge. The first is that it smuggles knowledge into the definition as justification (which is circular). The second is that it leads to an infinite regress (which is the same as not having any explanation at all).

Although this is where Plato left it, let me suggest the Thomistic solution. Knowledge is the unity between the knower and the known. If there is no unity between you and what you know, then you don’t know it, but something else. Of course the full details of how this occurs must be left to another time.