Knowledge

 


 

Recommended Reading

 

 

Gettier, Edmund, 1963. "Is Justified True Belief Knowledge?" Analysis, 23, pp. 121-123

 

Introduction

 

In this section of the course we’re going to be talking about knowledge, what it is, how to get it, whether it’s possible – all that sort of thing. But before we go on to look at some arguments for extreme skepticism, which say that we really can’t know anything, we should be clear that we know what we’re talking about when we say that we’re talking about knowledge. (That’s not quite the same thing as knowing what it is, so we’re not going to be begging any questions by talking about this in the introductory section.)

 

When we talk about having knowledge in English we can mean many different things. That’s because, just as a result of historical accident, several distinct but related concepts are named by the same word in English. This isn’t the case in all languages, but we are going to be talking in English, so we’d better be clear what we’re using the word to refer to. There are traditionally held to be three different kinds of knowledge:

 

1.             Knowledge by Acquaintance, which is the sort of knowledge that we claim when we say that: ‘I know Bob’ or ‘I know Robina;’

2.             Ability, which is what we mean when we say that ‘I know French’ or ‘I know how to ride a bike;’

3.            Propositional Knowledge, which is what we are claiming when we say that ‘I know that Bob is a builder’ or ‘I know that they speak French in Paris.’

 

It’s only the last case that we’ll be interested in. We call this ‘propositional knowledge’ because it claims that we are in some sort of relationship with a proposition. A proposition you should understand as being some sort of abstract thing that is expressed by an actual declarative sentence. The reason we want to talk about this abstract object rather than the sentence that expresses it is because we don’t want the content of knowledge to be confused with the manner of expressing it. A sentence in English like ‘John is in the garden’ expresses the same proposition as the French sentence ‘John est dans le jardin’, or the Latin sentence ‘John est in horto’ or etc. We think it’s absolutely clear that whatever it is I claim to know when I say ‘John is in the garden,’ is the same thing that I would claim to know by claiming that is the same belief as knowing that ‘John est dans le jardin’, or ‘John est in horto’ or etc.

 

Knowledge

 

In fact when we say that we know that P (where P stands for some proposition) it is generally said that we are taking an attitude towards the proposition P. Knowledge is thus said to be a Propositional Attitude, one of several attitudes that we can take towards propositions; such as hope, fear, despair, belief, … Now, one of these attitudes seems to be very, very closely related to knowledge, that is the attitude of belief. Knowledge seems to be a sub-attitude of belief: whenever we claim to know something it is implied that we also believe that thing. How can you know something that you don’t believe? It seems impossible.

 

But if knowledge is a kind of belief then what are the characteristics that separate it from just general belief? There is a standard answer to this which is that for some belief to be knowledge it has to be true, and it has to be properly justified. We can see immediately why truth gets in there: you can’t claim to know something that isn’t actually true. It would be impossible for anyone to know that the moon is made of green cheese, because it just isn’t. It is impossible to know that the world is flat, because it isn’t. Note that that doesn’t mean that people can’t think that they know that the Earth is flat, because obviously they can. In fact people can have all sorts of false beliefs, which they think are knowledge (otherwise why would they believe them?) but which are not knowledge. Knowledge isn’t to be identified with whatever people believe that they know, only with what they do know.

 

But true belief isn’t enough either. Suppose I decide that I will find out what the temperature is by throwing a dart at a dartboard. One day it just so happens that the number that that produces is the actual temperature, say 20oC. And so I believe that it is 20oC and it actually is 20oC. And so I have a true belief. But nobody thinks that this is knowledge. We have a phrase in English ‘Even a stopped clock is right twice a day’ that makes something like the same point. We use this phrase when we think someone has come to a conclusion or has a belief that happens to be true using a seriously flawed method of belief fixing. In such a case we don’t think that they know what they claim to know any more than the man with a stopped clock knows the time even when his clock says 2pm and it is 2pm. That man is not justified in his belief. Just so, we think that we need to have some justification for our true beliefs before they can be classed as knowledge. The belief and the fact that it is true can’t just be accidentally related, there has to be some connection between the two that justifies us in believing it.

 

Thus we arrive at the notion – which in one form or another is widely accepted – that Knowledge is justified, true belief.

 

Let’s look at each part of this definition. We talk about Belief in the Mind section, so it won’t be worthwhile going into the problems with it here, and you can just use your naïve unphilosophical views of ‘belief’ for the time being; but looking at the concepts of Truth and Justification  in these last lectures makes a nice symmetry with the first lecture’s Argument and Analysis.

 

Truth

 

You’ll recall in the A&A lecture we talked about how to go about determining whether arguments were good arguments, and central to that was the idea that a good argument would get us to a true conclusion. But what exactly are we claiming when we claim – as in a knowledge claim – that some proposition is true? There are three classic positions. The Correspondence theory, Coherence, and Pragmatism. We’ll look at these in turn.

 

Correspondence

 

The correspondence theory is probably the one that is most in tune with the naïve philosophical views of the common person. We generally take it for granted that what makes a sentences true is the fact that the world is the way that the sentence says that it is. So ‘Snow is white’ is a true sentence if snow is white, because ‘snow is white’ says that snow is white and there is a corresponding fact about the world; the fact that snow is white. We might be inclined, therefore, to say that a sentence is true if it corresponds to some fact about the world.

 

That is, in fact, just what the correspondence theorist of truth does say. But, although we all think to begin with that we know what we’re saying when we say that, a little bit of reflection reveals that we haven’t really clarified the notion of truth at all, for now we have to answer the question: what is it for a sentence to correspond to a fact? We know what it means to say that a picture of a thing corresponds to the thing itself. (Actually, we don’t, but we sort of think that we do.) It means that some elements of the picture are in the same or systematically modified relations to each other as are the parts of the object itself. So a picture of a lion has a picture part depicting a head at one end and a picture part depicting a tail at the other end, and a lion has a head at one end and a tail at the other. But it isn’t obviously the case that this is how we can understand the correspondence of sentences and facts. It’d be hard to argue that the sentence ‘snow is white’ looks like the fact that snow is white. Hard, I say, but some philosophers (Russell, Wittgenstein) have given it a shot.

 

The picture theory to one side, any correspondence theory is going to have to account for all sorts of strange situations that sentences describe but that don’t look likely to be independent facts: things like, for example, negative claims. If I say that the world is not flat, I am not claiming that the world is any particular way, only that there are some ways that it is not. What sort of fact does that correspond to? Or does it correspond to a class of facts?

 

Coherence

 

Rather than going on to look at the ways that defenders of the correspondence theory have tried to save it from this sort of objection, we’ll move on to the coherence theory. In this theory, the idea is that a proposition is true if it coheres with all the other propositions that are held to be true. Thus ‘snow is white’ is true because all the logical implications of that statement – like ‘snow is not green’, ‘snow is the colour of copier paper’, ‘water crystals are translucent to all visible wavelengths of light’, and so on are also held to be true; and, in fact, all the ways in which that statement can be connected to other statements that are believed to be true or false make sense if ‘snow is white’ is asigned the truth-value True. Logically speaking, the statement ‘snow is white’ is consistent with all the other statements expressing your beliefs. You cannot derive a contradiction from ‘snow is white’ plus all your other beliefs. Note that one of the statements you are going to hold at some stage to be true is that ‘I see snow and it is white’, so there is a way to connect this to the actual way the world is. But it’s a bit indirect and doesn’t depend upon a troublesome notion of ‘correspondence.’

 

Coherence theories also have their problems, of course, and the two major ones are that (1) it’s almost guaranteed that some of the things that one believes are inconsistent with some of the other things that one believes. I, being an ignoramus in matters macroeconomic, may believe certain things about balance of trade, or comparative advantage, but I may also believe that classical economics gets the story about these things right, whereas, unbeknownst to me, classical economists contradict my beliefs about the balance of trade and comparative advantage. So I have an inconsistent set of beliefs. But this means that for any sentence – like ‘snow is white’ – I can derive contradictions, even if just from my beliefs about economics. But this means, finally, that I can’t have any true beliefs. That seems harsh.

 

The other problem is that if coherence does mean consistency as I’ve been saying, then what is consistency? You can’t say ‘a set of sentences are consistent if they can all be true together’ because now you’re using the concept of truth to define the concept of truth, and that’s viciously circular. So it might be that the idea of a coherence theory is actually incoherent.

 

Pragmatic

 

A third attempt to clarify the notion of truth is the idea of a pragmatic defnintion of truth. This is the claim that ‘truth is what works.’ So, ‘snow is white’ is true because when one takes this to be true one is able to interact successfully with the world. For example, one is able to design cunning snow camouflage to fight your enemy in the Winter War; whereas if one took ‘snow is green’ to be true, one would have less success, and one would be an easy target, and one would be shot.

 

But this has many of the same problems as the coherence theory together with some strong objections peculiar to it. For example, as long as the Sun-centred theory of the solar system was less well-developed than the Earth-centred theory, the Earth-centred theory will be the one which give the best results and is thus the ‘true’ theory. But that seems wrong. Surely the Earth-centred theory was always just not true.

 

Justification

 

So we have some difficulties knowing what we mean by truth. That’s going to make some difficulties for understanding what we mean by knowledge when we define that as justified, true belief. But let’s move on to see what we can say about justification in that definition.

 

Remember that the point of the justification criterion is that it can be just a coincidence that the belief that we have is a true belief; and we decided that what was lacking was a good reason to have that belief. If we had a good reason to believe a true thing then we would have knowledge. On the other hand, most philosophers will also say that just because we have a good reason to believe P, it doesn’t necessarily follow that P is true. In the past, for example, people may have had good reasons to think that the world is flat – after all, if it wasn’t flat then people would fall off where it was sloping. If the only thing that counted as a justification for a belief was something that made its truth absolutely certain, then we wouldn’t need to have ‘truth’ in the conditions for knowledge. We could just say knowledge is justified belief and the truth of that belief would follow from its being justified. However, as we will see when we look at some skeptical arguments later, infallibly justified beliefs are very hard to come by. In fact asking for that condition may remove the possibility of knowledge altogether. But that makes the whole definition of knowledge rather pointless, and we are pretty sure we do  know some things – in any sensible sense of the word ‘knowledge’. For example, I surely know that I am standing in this room talking to you. It is therefore widely accepted that justifications are fallible.

 

Apart from fallibility/infallibility, there’s another characteristic of justifications that is of interest. A theory of justification can be either what is called internalist or externalist. An internalist theory of justification is one in which the properties which make a reason to believe something a justification are properties that are purely internal to the subject. We’ll see some examples in a second, but one way to think of this is to say that on the internalist view it is possible for the subject to determine whether their belief is justified or not by simple awareness of their own internal states and processes. By contrast, for the externalist the existence or otherwise of a justification is a judgement to be made from the omniscient observer’s perspective. Whether a reason to believe (or a reason for belief) is a justification depends upon real, objective properties of that reason.

 

There are three classic views of justification that we’ll list here: reliabilist, foundationalist, and coherentist.

 

Reliabilism

 

The reliabilist is an externalist. According to his theory, we are justified in a true belief if the belief is properly formed by means which reliably lead to true beliefs – whether of not the believer realises that that is the case. For example, we are justified in believing that we are in a lecture hall at the moment because that belief is formed by perceptual mechanisms and reasoning processes that in almost all cases result in true beliefs being formed. That’s fairly easy to understand, and we’ll see how this sort of thing is attacked by Descartes in the next lecture,) but consider that if I happened to be a clairvoyant who could close his eyes and see what was going to happen in the future, and if what I said was going to happen really did almost always happen, then, no matter whether or not I have any idea of what goes on in my head when I close my eyes to take a clairvoyant ‘reading’, the reliabilist would say that I have knowledge, because the process is really reliable.

 

Others, however, think that the very fact that that sort of oracular pronouncement can be classed as a piece of knowledge is evidence that the reliabilist position must be missing something. Presumably it’s missing something in the nature of a connection between the formation of the belief and the awareness of the reliability of the formation. It doesn’t count as knowledge unless the believer knows how the justifictation works – which some might say is exactly what was mean by requiring there to be a justification in the first place.

 

So we seem to need to have an awareness of the way that the justification proceeds. This suggests that justification should be understood as an internalist process, and that justification is a judgement that can be made by the believer from his own resources. There are various ways that this can be thought to occur.

 

Foundationalism

 

In the first place we could claim that there are certain fundamental, or basic beliefs, and that other beliefs are derived from them by some fallible but powerful method. From what we said in the previous lecture on Arguments and Analysis, the other beliefs must be justified either as deductively valid consequences of those beliefs or as inductively strong consequences (in which case they’re not indefeasible.) The class of basic beliefs, which are presumably self-justifying or justified by some method other than deduction or induction from other beliefs, is a stumbling block here. It is hard to know what exactly can go into this class, and until we get something in there we can’t even start to build up knowledge by deriving other beliefs from that set. When we look at Descartes in the next lecture we’ll see what he takes to be a basic belief that can get us started.

 

Coherentism

 

On the other hand, if we like the idea of beliefs being supported by other beliefs, then we might prefer a type of coherence theory of justification – which is rather similar to the coherence theory of Truth that we looked at above. In this case we say that a belief is justified if it coheres with the other beliefs that a subject holds, and that there are no beliefs that are justified outside this network of beliefs.

 

The difficulty with this is, however, that a subject may have a set of beliefs that are all what we would call false and yet are absolutely coherent. For example, someone who has immersed themselves in a fictional world – perhaps something like Second Life (which is a type of virtual world) – could have thoroughly coherent beliefs which are all false about the world. The intuition that we have here is that there needs to be some connection beyond the mere network of mental states in order for a justification for beliefs about the world to be legitimately a justification for beliefs about the world. And so we are brought back to the externalist position: that there is something true and beyond the subject that is essential for a justification.

 

Gettier Problem

 

Of course, all this has been based on the idea that justified, true belief is a satisfactory analysis of knowledge, and all we have to do is to make sure we know what is meant by true, and justified, and belief; but even this was disputed by a very famous and very short paper by Edmund Gettier in 1963. He gave cases in which a belief could be true, and justified, and yet we would still not think that there was knowledge involved. The paper is so succinct that I can give the second of his examples just as he presented it:

 

Let us suppose that Smith has strong evidence for the following proposition:

f.        Jones owns a Ford.

Smith's evidence might be that Jones has at all times in the past within Smith's memory owned a car, and always a Ford, and that Jones has just offered Smith a ride while driving a Ford. Let us imagine, now, that Smith has another friend, Brown, of whose whereabouts he is totally ignorant. Smith selects three place names quite at random and constructs the following three propositions:

g.       Either Jones owns a Ford, or Brown is in Boston .

h.       Either Jones owns a Ford, or Brown is in Barcelona .

i.         Either Jones owns a Ford, or Brown is in Brest-Litovsk.

Each of these propositions is entailed by (f). Imagine that Smith realizes the entailment of each of these propositions he has constructed by (f), and proceeds to accept (g), (h), and (i) on the basis of (f). Smith has correctly inferred (g), (h), and (i) from a proposition for which be has strong evidence. Smith is therefore completely justified in believing each of these three propositions, Smith, of course, has no idea where Brown is.

But imagine now that two further conditions hold. First Jones does not own a Ford, but is at present driving a rented car. And secondly, by the sheerest coincidence, and entirely unknown to Smith, the place mentioned in proposition (h) happens really to be the place where Brown is. If these two conditions hold, then Smith does not know that (h) is true, even though (i) (h) is true, (ii) Smith does believe that (h) is true, and (iii) Smith is justified in believing that (h) is true.

 

Gettier concluded that justified, true belief is not sufficient for knowledge, but most philosophers are inclined to think that it just means that we have a lot more work to do in determining exactly what sort of justification is sufficient for knowledge. There’s nothing in the Gettier example to rule out the idea that some modification of the notion couldn’t solve that problem.