How Many Types of Truth?

What should we make of these answers, or even the original question itself? Perhaps the reason why we get such a diverse and obscure set of answers is that the original question is itself too general. Let’s make it more precise.

What is it for a proposition to be true? That is, what makes a proposition true? Before considering possible answers, let’s make sure we are clear about what is being asked. First, a proposition is what we express with statements, or declarative sentences. Compare this use of sentences to others, such as to…

• Ask a question (e.g., What time is it?)
• Give a command (e.g., Close the door!)
• Utter an exclamation (e.g., yippy!)
• To greet or say goodbye to someone (e.g., hello).

One big difference between these sentences and declarative sentences that we use to express propositions, or make statements, is that only declarative sentences can be true or false. The others cannot.

To see this more clearly, note how the following sentences do not make grammatical sense:

1. It is true that what time is it?
2. It is true that close the door!
3. It is true that yippy!
4. It is true that hello.
5.  

The reason is that questions, commands, exclamations and greetings have no truth-value. They are neither true nor false. On the other hand, declarative sentences do have truth-value; i.e., they are either true or false. Consider, for example, that the following makes perfect sense.

    5. It is true that the Earth revolves around the sun.

Also, notice that beliefs are very much like statements, in the sense that both are about something, and both have truth-value. The statement

    6. “Utah is in the United States” is about the location of Utah.

Likewise my belief that

    7. “Iran is a threat to its neighbors” is about Iran’s relationship to its neighboring countries.

Now that we have clarified, let’s consider some possible answers to our question. Here again is our question: What makes a statement (belief) true?
As a first attempt to answer this question, someone may offer this:

    8. What makes a statement (belief) true is that most people believe it.

This answer might initially seem to have a lot going for it. After all, how could a majority of us be wrong. The evidence, however, tells us that this is not right. There are countless cases in which a majority of people believed something, but were mistaken. Here is just one example. Prior to Galileo nearly everyone believed that the Earth was the center of the solar system, and that the sun, moon, planets, and stars revolved around the Earth. So, 1,500 years ago nearly everyone (if not everyone) believed and statemented that

    9. The Earth is the center of the solar system.

However, we now have very good evidence that they were wrong. That is, we now know that (9) is false. So, the mere fact that a majority of people statement or believe something cannot be what makes it true. Perhaps what makes something true is that there is evidence for it. So, perhaps the following is the right answer:

    10. What makes a statement (belief) a true is that we have evidence for it.

This is certainly better than (8). After all, having evidence of something seems to play an important role in how we know, at least in part, that something is true. While this is a good attempt, unfortunately it won’t due either. The reason is that we often have evidence for a false statement. Here is an example. Suppose that Sam commits a crime – he murders his neighbor Fred. However, suppose that Sam is very crafty. He has carefully studied the work of crime scene investigation and has learned how to cover his tracks and make it look like someone else did it. So, he does just this. Sam leaves evidence that his other neighbor Jim murdered Fred. So, when the detectives and crime scene investigators show up, and gather all the evidence, they conclude that it was Jim who murdered Fred, because the evidence supports that. That is, they have evidence, let’s even suppose good evidence, for

    11. Jim murdered Fred.

In spite of the evidence, we know that (11) is false. While the above story was fictional, we know that there are actual cases where this occurs. We also know that it happens in the sciences. Consider (9) again:

9. The Earth is the center of the solar system.

Not only did most (all) believe this at one time, but astronomers had good evidence that it was true. This is one reason why it was hard for Copernicus and Galileo to get scientists to accept that it was false. Ok, perhaps what makes a statement true is that it is impossible to prove it false. So, we have

    12. What makes a statement (belief) true is that it is impossible to prove it false.

While it is true that if it is impossible to prove a statement false then it is probably true, this seems too strong. After all, there are some statements, which while they are in fact true, they could have been false, and had they been false then we would be able to prove them false. For example, it is actually true that Barack Obama was elected to be the 44th president of the United States. However, it is possible that he wasn’t. American voters could have given a majority vote to John McCain instead. Had they done so, then Obama would not have been elected to be the 44th president of the United States. So, while

    13. Barack Obama was elected to be the 44th president of the United States.

is actually true, it could have been false. And, had it been false, then surely we would have been able to prove it to be false. So, since (13) is possibly false, and is such that had it been false we would be able to prove it to be false, it follows that it is possible to prove (13) false, even though it is actually true. Therefore, (12) above is too strong. Someone may be led to conclude from all of this that there isn’t anything that makes a statement (belief) true. They may think that either there is no such thing as a true statement, or that while there are true statements, there is nothing that makes them true. The first suggestion, that

    14. There is no such thing as a true statement,

won’t work. The reason is that (14) itself is a statement. Thus, if what it says is true, then (14) cannot be true. That is, (14) is true only if it is false. This is clearly incoherent. So, we don’t want to go to the extreme of saying that there are no true statements or beliefs. But, the suggestion that there are true statements, but nothing that makes them true seems too strong as well. Surely what makes “Utah is in the United States” true is that Utah really is in the United States. The last point gets us much closer to the answer to our question. Some have proposed that what makes

    15. Utah is in the United States.

true are the conditions of the world – namely the state of affairs of Utah actually being located in the United States. We can generalize from here.

    16. What makes a statement (or belief) C is true is that C corresponds with the actual world.

This theory goes back at least to the ancient Greek philosophers. It is known as the Correspondence Theory of Truth (or CTT for short).
There are a few important points that must be mentioned about CTT. First, it truly is general. It covers statements or beliefs about anything. For example, we make statements and have beliefs about the concrete physical world. E.g., we believe and statement that

    17. Water is composed of H2O.

People also make statements and have beliefs about the concrete non-physical world. E.g., many believe and statement that

    18. God (of Christianity) exists.

And, we make statements and have beliefs about countless other matters. Here are just a few more. We statement and believe that ‘2 + 2 = 4’, that ‘murder is wrong’, that ‘Santa Claus is jolly’, etc. CTT covers all of these. In each case, what makes the statement or belief true is the condition of the world. If the world contains the corresponding appropriate states of affairs, then the statement is true. It is false otherwise.
As a last point, it is worth elaborating on what we mean by ‘actual world’. First, by ‘actual world’ we do not mean ‘Earth’. Unless Earth and its inhabitants is all that exists, the actual world includes far more than Earth. Second, ‘world’ does not refer to our collective beliefs. While our beliefs are members of the world, the world includes far more than our beliefs, unless all that exists is our beliefs. Instead by ‘actual world’ we mean the sum total of all the states of affairs that exist. And, it may well be the case that the actual world contains a variety of different types of facts. That is, there could very well be concrete and/or abstract states of affairs, as well as physical and/or non-physical states of affairs.

Of course one may ask:

    19. Who’s to decide which states of affairs exist (i.e., what states of affairs does the world contain)?

If (19) is intended to be taken literally, then the answer varies. For some states of affairs, no one decides that they exist – they just do (e.g., that 2+2=4). For others, perhaps God created them. Still for others, some human created them. However, perhaps the question really means:

    20. How do we know which states of affairs the world contains?

The answer to this is difficult to give. Fortunately, we do not have to answer it in order to say what it is for a statement or belief to be true. But, we can say that, like states of affairs, which states of affairs are members of the actual world is, for the most part, independent of what we think or believe or statement. Though, of course, one’s belief itself is dependent upon one believing it. So, of course, mental states of affairs are dependent upon each individual that has them for their existence. But, states of affairs that are not mental do not depend for their existence upon what anyone thinks, believes, or statements.

In sum, the actual world contains all the objects and states of affairs that exist. The present proposal is that a statement is true only if it corresponds to the actual world. This makes truth objective and discoverable. It makes science, philosophy, and religion worthy investigations.

While CTT is very attractive, and it is very close to what it is for a statement to be true, it has a weakness. It does not give cover what are called negative existential truths, or generalizations. A negative existential statement is a statement that something does not exist. Here’s an example:

    21. Santa Clause does not exist.

It cannot be the case that there is something in the world that corresponds with (21), since what makes it true, if anything, is the lack of something existing.

There seems to be an easy fix for this, for our purposes. We could say that what makes a statement is true is the overall state and structure of the world, such that if a statement about the world says that it is or is not some way, then the statement is true if and only if it is or is not that way. For this adjustment, we don’t need the statement to correspond to any existing thing, but just to be about the world as it really is. Thus, we propose the following, which has all the benefits of the correspondence theory, without its weakness (since the update also covers negative existentials and generalizations).

    22. What makes a statement (or belief) C is true is that the actual world is just as C says it is.