05/06/2026

 

Samuel Clifford

 

What is Knowledge?

 

Finding a precise definition of knowledge is difficult. However, we can look back through the history of philosophy to find how it is typically defined. According to the traditional approach, knowledge has been defined as possessing three distinct parts or criteria: justification, truth, and belief. One notable philosopher who defined knowledge in this way is Plato. In Theaetetus, Plato presents a dialogue between Theaetetus and Socrates. Socrates says, “Now when a man gets a true judgment about something without an account, his soul is in a state of truth as regards that thing, but he does not know it; for someone who cannot give and take an account of a thing is ignorant about it. But when he has also got an account of it, he is capable of all this and is made perfect in knowledge.”  

The first step to knowledge is belief. A person must have a belief, or something they hold to be true, in order to have knowledge. The claim to have knowledge must start with belief. We cannot know things that we don’t have a belief about. Thus, belief is a basic component of knowledge. The second step to knowledge is justification. Since belief can be wrong, we should want to know if a belief is true before we can claim to have knowledge of it. The final part of knowledge is truth. A person can believe and justify something and that belief can still be wrong. Therefore, for a claim to count as knowledge it must also be true.

 

Can we Know?

 

The central problem in the epistemology of perception can be summed up by just one question, “Can we know?” This question has brought forth an idea known as skepticism, which, in its philosophical definition, is the theory that certain, or in radical cases all, knowledge is impossible. skepticism, also spelled scepticism, is essentially in opposition to dogmatism. Dogmatism is the tendency to state or believe something is incontrovertibly true without consideration of others opinions or evidence. There are many different kinds of skepticism, from Cartesian skepticism to Irrationalism, all share a similar quality, never assume, always doubt. 

 

Are Skeptics correct? Can we know anything? Can we justify any of our beliefs? These are questions that one can only attempt to answer. However, skepticism is inconsistent and self-defeating. When a skeptic claims “we cannot know anything,” they are making a claim about knowledge. If the skeptics claim is false, then no one needs to worry about their claim. However, if their claim is true, then their claim is self-contradictory, because we know at least one thing, that we cannot know anything. 

 

John Pollock, in his book Knowledge and Justification, argues that we cannot accept skepticism because it is against common sense. Every knowledge claim consists of evidence and a conclusion. The skeptic asserts, in essence, that the evidence which is contained in the premise of an argument is true, but the conclusion is false. Think of it this way:

 

1. I feel excessive heat on my hand.

2. Someone tells me my hand is on fire.

3. I see my hand is on fire.

Conclusion: My hand is on fire.

 

The skeptics claim that the three premises are correct, but the conclusion is false. However, according to Pollock, if the conclusion is false then one of the premises is false. It's more reasonable to believe one of the premises is wrong than the conclusion, yet, skepticism accepts the premises and disregards the conclusion. Which, in result, puts skepticism against common sense. 

One philosopher, Thomas Reid, a contemporary of the great skeptic David Hume, disagreed with some of Hume’s arguments and set out to critique them. Hume argued that even our most basic beliefs must be justified by philosophical or rational arguments. Reid, however, argued that rational proofs of belief are inappropriate, for it would demand an infinite regress of justifications, as each justification would need a rational justification for itself. In other words, these basic beliefs are the basis for all other beliefs, but they cannot be proved. Reid also argued that basic beliefs aren’t based in blind prejudice but instead these beliefs reflect the very constitution of our rationality, and thus are known through intuition, not demonstration.