2

Objectivity

People sometimes wonder about the nature of truth because they are interested in the question whether anything is "objectively" true. Does the truth depend on what people, or the right people, believe? Or are there some claims that are true regardless of what anyone thinks? One idea of an "objective" truth is the idea of a claim whose truth or falsehood does not depend on what anyone believes.

A second set of questions also falls under the heading of objectivity. Those questions concern the relationship between truth and knowledge. Sometimes we can tell whether a claim is true or false, and sometimes it is impossible for us to know one way or the other. If there is no way to tell whether a claim is true or false, can it even be true or false? One idea of "objective" truth is the idea that the truth of a claim does not depend on whether or not we could know it. There could be claims that are true but unknowable. According to some philosophers, though, the idea of an unknowable truth is nonsense. On their view, if it is impossible to know whether something is the case, then there simply is no fact of the matter either way. These philosophers thus think of the limits of possible knowledge as the limits of truth and, in that sense, the limits of reality

This chapter concerns the three-way debate over objectivity. On one side is realism, the view that there are some claims whose truth does not depend on their being believed by anyone or even on the possibility of anyone's knowing them. On another side is relativism, the view that the truth is always a matter of opinion, in the sense that the truth of any claim always depends on who believes it. The third contender is anti-realism, the view that part of what makes a claim true is the fact that we can know it, and so claims we cannot know to be true or false cannot be true or false. Each view presents a different picture of how the world is, and each has its own advantages and disadvantages. This chapter discusses those advantages and disadvantages, with the upshot that a mild form of realism is the most plausible of these views.

2.1    Three Pictures of Reality

Realism, anti-realism, and relativism present different views of the world and its relationship to our minds. Realists take the commonsense view that there is a world "out there," and the facts are as they are irrespective of what anyone thinks about them. There are some claims that would be true even if no one believed them, or false even if everyone did. Moreover, although we may be able to acquire some knowledge about the mind-independent world, claims are ordinarily knowable because they are true, not true because they are knowable. What makes a claim true need not have anything to do with the possibility of knowing it. Realists might disagree with each other about which parts of reality are mind-independent, but they agree that something is.

Astrophysicists say parts of the universe more than about 62 billion light years away are too distant for any information from there to reach us - ever (Gott et al. 2005). Consider the claim (whose truth we could not possibly know) that there are an odd number of water molecules exactly 63 billion light years from Earth. A realist is apt to say that, regardless of whether anyone believes or disbelieves that claim, and despite the fact that we have no way of knowing one way or the other, the claim is either true or false. Either there are an odd number of water molecules 63 billion miles away, or there are not.

Relativists think of the world as made up, like a story. Truth and falsehood depend on what people believe. And just as there is no such thing as absolute "to the leftness," but only being to the left of something, there is no such thing as absolute truth, only truth for someone. A table might be to the left of the window but not of the stove, and a claim might be true for one person but false for another. Belief is what makes the difference. On the relativist view, what makes a claim true for someone is that they believe it, and what makes it false for someone is that they disbelieve it.

Suppose Jill has told a joke. Maybe some people think it is funny and some people think it isn't. It's very tempting to think the joke is funny for those who think it is, but it isn't funny for those think it isn't. It's also tempting to think that is all there is to it. There is no underlying fact about whether the joke is "really" funny or not, because part of what it means for something to be funny is for people to think it's funny. Relativists think all claims are like the claim that Jill's joke is funny. Not only the truth about funniness, but all truth depends on what people believe, and it is always someone's truth. What a person believes is true for her; what she disbelieves is false for her; and where she has no opinion, there is neither truth nor falsehood.

Anti-realists do not think truth depends on belief, and they do not think that all truth is someone's truth. But they do think truth is mind-dependent in another way. According to anti-realists, a claim cannot be true unless it is possible to find out or know it is true. Likewise, a claim cannot be false unless it is possible to find out or know it is false. If there is no way to know that a claim is true, anti-realists think, then that claim must not be true - it must either be false or have no truth value at all. On the anti-realist view, the concepts of truth and knowability are tightly linked because part of what it means for a claim to be true is that there is a way we could find out that it's true. This makes truth mind-dependent because the limits of possible knowledge are also the limits of reality. If there is no way to find out whether there are an even or odd number of water molecules exactly 63 billion light years from earth, then there is no fact of the matter about it. It's neither true nor false that there is an even number, and it's neither true nor false that there is an odd number. Instead, the question represents a gap in reality.

There are thus two big questions to be addressed in the debate among realists, relativists, and anti-realists. First, is anything true irrespective of what anyone believes? If so, then relativism is incorrect. Second, is there anything that is true even though there is no way, in principle, for anyone to know that it is? If so, then anti-realism is incorrect.

2.2    Realism

The realist picture of reality draws on two important aspects of our experience. First, we sometimes find that we have mistakenly believed something that was not true. Second, we sometimes discover truths we were unaware of before. These experiences allow us to distinguish between how things really are and what we happen to believe. A natural way to make that distinction is to think of the world as "out there" and independent of us. The world is a collection of objects or facts that are as they are regardless of what we think, and even regardless of what we could believe or know.

Consider, for example, the claim that the earth is shaped more like a sphere than a pancake. People used to disbelieve that claim, but they later discovered that they were mistaken. They discovered that things were not as they thought they were. But what if there had been no way for anyone to know the shape of the earth? What if no intelligent life had ever existed in the universe? Still, we tend to think, the earth would have been shaped more like a sphere than a pancake. The shape of the earth is supposed to be exactly the sort of thing that is indifferent to what we happen to believe, or even to what it is possible to know.

One of the greatest appeals of realism is its explanatory power. Realism explains why it is possible for beliefs to be mistaken. For example, it is possible for a belief about the shape of the earth to be mistaken because the shape of the earth does not depend on what anyone thinks about it. Realism also provides a way to make sense of what happens when we discover something new. There are facts that are out there, independent of us, that we have not yet come to know. Discoveries happen when we find a way to know them.

But realism goes further than that. Not only does it say there are claims whose truth does not depend on our believing them, but it says there are claims whose truth does not depend on the possibility that we could know them. Why should we think there are such facts?

One reason applies what we already know about the world. What makes it true that the earth is round, for example, appears to be something about the earth itself, not its relationship to intelligent life. After all, it was true long before there were any intelligent beings to know it, and it would have been true even if those intelligent beings had never existed. Given what we know about the world, then, there seem to be some claims whose truth does not require the possibility of their being known.

Another reason has to do with the fact that there are some claims whose truth or falsity we cannot know. Consider the claim that the last dinosaur chipped a tooth ten minutes before dying. We have no way of finding out whether that claim is true or false. However, it is natural to suppose that the dinosaur either did or did not chip a tooth ten minutes before dying. Either way, then, there is something that is true but impossible to know.

The realist conception of the world...