PHILOSOPHY OF HUMAN NATURE:
PHILOSOPHY AND TRUTH
Brian B. Clayton
(Revised, 8 January 1998)

Introduction to the course

1. Why study philosophy?

A. Philosophy is helpful in any career that requires creativity, problem-solving and the ability to argue for one's views.

B. Philosophy helps us to think well and carefully, and cultivates at least four intellectual skills: analysis, assessment, argumentation, articulation.

C. Tom Morris has said that philosophy helps us to think carefully and deeply about the most important things in our lives.

 2. What is philosophy? A. "Philosophy" means "love of wisdom."

B. Wilfrid Sellars has said that "The aim of philosophy, abstractly formulated, is to understand how things in the broadest possible sense of the term hang together in the broadest possible sense of the term."

C. I have found it to give me a license to investigate anything which I find of interest. Philosophers are the "big picture" people.

D. On my understanding of philosophy, we work on our worldviews (Weltanschauungen).

 3. What will this course be like? A. This is answered by looking at the syllabus. Note, especially, the goals of the course and the course requirements. If the class participation requirement bothers you, remember that asking a question also counts as participation. (If you are still bothered by this, see me for some suggestions on how to handle it.)

B. There are several major philosophical issues which will run throughout our readings. You can find these issues identified on the syllabus in the "Reading/Discussion Questions ("Focus Themes")."

 

 Truth

1. "Philosophy" means "love of wisdom." But what is wisdom?

2. Wisdom involves correct understanding, correct judgment, and correct action. Correct understanding involves understanding the way things are--i.e., understanding the truth. But, why think there is any such thing as the truth?

3. Begin with the following assumption:

(T) There is no truth.

Is (T) true or false? If (T) is true, then it is true that there is no truth; but then there is at least one truth and so (T) is false. On the other hand, if (T) is false, then it is false that there is no truth; but this just means that there is truth. So, in either case, there is (at least one) truth. In fact, there are an infinite number of truths. E.g., it will be a truth that there is at least one truth, and it will be a truth that it is a truth that there is at least one truth, and so on ad infinitum. The interesting question is whether there are any other truths and, if so, what they are. Before we get to this issue, we need to ask, what are the sorts of things which can be true or false?

4. It is obvious that we can use "true" to describe friends and love, among other things. However, when we were thinking about truth in the context of (T), we primarily had in mind statements. What are statements?

5. Statements are sentences which are either true or false; not all sentences are statements since some sentences are commands, exclamations or questions. Philosophers often say that statements are expressions of propositions, where a proposition is an abstract entity roughly equivalent to the meaning of a statement. For example, the English statement "The snow is white" expresses the same proposition as the German statement "Der Schnee ist weis"; i.e., both statements have the meaning that the snow is white. So, if we want to be picky, we might say that it is propositions that are true or false; statements, in turn, are true or false depending on whether the propositions they express are themselves true or false. But, we won't be picky and will continue to say that statements are either true or false.

6. We can also say that beliefs are true or false. This is because, when I believe something, it is a statement (or proposition) which I am believing. For example, I may believe that the snow is white, and my believing this is a matter of believing that the statement "The snow is white" is true. So, we may say that beliefs are true or false depending upon whether the statement believed (and hence the proposition believed) is true or false. For example, my belief that snow is white is true just in case snow is white.

7. We need to make a further, admittedly rough, distinction: we need to distinguish objective truths from subjective truths. We can say, speaking in a very rough way, that we are dealing with an objective truth when the truth involved is independent of people's preferences about things. For example, 2+2=4 is an objective truth because the truth or falsity of this does not depend on my (or anyone else's) preferences about the matter. In fact, when I was first learning basic math facts, there were probably a number of times when I would have preferred that 2+2 did not equal 4 (but rather equalled 3 or 5 or some other number); my preference did not have any effect at all on whether 2+2 really did equal 4.

8. When we are dealing with a subjective truth, however, the truth involved does seem to depend upon people's preferences. Consider, for example, the following statement:

(A): Asparagus tastes better than Brussels sprouts.

This is an expression of preference: the truth of (A) seems to depend on what someone thinks and/or feels about asparagus and Brussels sprouts. Notice, though, that there is some truth of the matter. For example, (A) can be shorthand for "I prefer the taste of asparagus to the taste of Brussels sprouts," and this is a statement which is either true or false. Or, (A) could be shorthand for "More people prefer the taste of asparagus to the taste of Brussels sprouts"--and this, too, is a statement which is either true or false. However, the truth in both these cases is still a function of people's preferences, and preferences themselves are neither true nor false (although as desires they can be appropriate/inappropriate). So, we can call the truths in these cases "subjective truths."

9. We need also to differentiate between genuine disagreement and differences of opinion. A genuine disagreement occurs when I say that some statement (x) is true and someone else says that the same statement (x) is false. Differences of opinion do not involve contradictory statements in this way. For example, if I say "I prefer the taste of asparagus to the taste of Brussels sprouts" and you say "Well, I prefer the taste of Brussels sprouts to the taste of asparagus," then we have a difference of opinion but we do not have a genuine disagreement. You are not saying that it is false that I prefer the taste of asparagus to the taste of Brussels sprouts; you are merely asserting a different claim (namely, that you prefer the taste of Brussels sprouts to the taste of asparagus). If, on the other hand, I say "I prefer the taste of asparagus to the taste of Brussels sprouts" and you say "No you don't! You prefer the taste of Brussels sprouts to the taste of asparagus," then we would be having a genuine disagreement; you would be saying that my assertion is false. (And you would be wrong since I cannot stand Brussels sprouts but have a great fondness for asparagus.) As this case should make clear, we can have genuine disagreements with respect to particular subjective truths, but we cannot have a genuine conflict between any two subjective truths. In fact, most of our disagreements are over objective truths. In any case, whenever we find ourselves having a genuine disagreement, we are dealing with truth.

10. What are some properties of objective truths (as expressed in statements)? First, objective truths are non-relative. Second, the truth of statements expressing objective truths is not the same thing as the justification for believing that those statements are true. Third, the truth of statements expressing objective truths is different from our ability to know that the statements are true. We'll take these up in turn.

11. First, let's define some terms:

(DR) Descriptive Relativism =df., as a matter of fact, what one person believes to be true may not be what another person believes to be true.

(SR) Simple Relativism =df., what is true for one person may not be true for another person.

 (DR) is the most straightforward of the terms. It simply claims that people disagree with each other. One person may believe that raising interest rates will slow the growth in GNP, while another person may believe that raising interest rates will not slow the growth in GNP.

12. But, what does (SR) mean? One way of understanding it is to say that it means that if one person believes that asparagus is a vegetable and another person believes that it is not a vegetable (maybe this person believes it is a dairy product and believes that no dairy products are also vegetables), then it is both true that asparagus is a vegetable and true that asparagus is not a vegetable. If this were the proper interpretation of (SR), then contradictory statements would be true. So, if we interpret (SR) in this way, then we can conclude that (SR) is false. We can see this by considering the following argument.

If (SR) is true, then contradictory statements are true. But contradictory statements cannot both be true. So, (SR) is false. A further argument showing that (SR) is false is the following: If (SR) is true, then all beliefs are true. If all beliefs are true, then there are no false beliefs. If there are no false beliefs, then I am never mistaken. But, I have been mistaken. So, there are false beliefs. So, not all beliefs are true. So, (SR) is not true. 13. An alternative way of understanding (SR) might be to say that it means that what one person believes to be true may not be what another person believes to be true. We can capture this in the following modified version of (SR): (MSR) Modified Simple Relativism =df., what is believed to be true [by] one person may not be believed to be true [by] another person. (The underlined portions of this definition indicate words added to the original definition, and the brackets indicate where words in the original definition have been eliminated and others substituted for those eliminated.) However, (MSR) is really nothing other than (DR)--i.e., Descriptive Relativism. So, (MSR) doesn't tell us anything new and earth-shattering; we already knew that people sometimes genuinely disagreed with each other.

14. But the supporter of (SR) might say that we have missed the point. The supporter of (SR) might say that the existence of all of these genuine disagreements and differences of opinion must show that there really is no truth but many different truths, and that this is what the original (SR) was trying to claim. However, we can see that (DR) does not entail (SR) by the following argument:

Let's assume that (DR) is true and that (SR) is false. (Our everyday experience warrants the truth of (DR) and the arguments above warrant the view that (SR) is false.) If we assume for the sake of argument that (DR) entails (SR), and if we know that (SR) is false, then we can conclude that (DR) is false. So, we could conclude that (DR) is true and Not-(DR) is true. But both of them cannot be true, and we seem to have more warrant for thinking that (DR) is true than for thinking that Not-(DR) is true. So, we ought to reject the assumption that we made for the sake of argument and conclude that (DR) does not entail (SR). 15. But, the supporter of (SR) might say, this just leads to intolerance. That is, supporters of (SR) often see a link between relativism and tolerance. Let's formulate the principle of tolerance (PT) in the following way: (PT) Principle of Tolerance =df., one ought to be tolerant of others' beliefs insofar as those beliefs are defensible. The supporter of (SR) might say that rejecting (SR) will lead us to reject (PT), and since we think (PT) is true, we ought to accept (SR) which provides a reason for accepting (PT). However, consider the following principle: (PI) Principle of Intolerance =df., those who disagree with me ought to be tortured until they come to say that they agree with me, and then they ought to be summarily executed before they can change their minds. Let's say that I believe (PI). What should the supporter of the first interpretation of (SR) say about my belief? Well, it is true for me. That is, (PI) is true. So, (SR) seems to be compatible with both (PT) and (PI) even though (PT) and (PI) seem clearly to be at odds with each other. So, even if (SR) were true, it would provide no particular reason for preferring (PT) over (PI); it seems to be neutral between these two principles. So, (SR) provides no particular reason for being tolerant rather than intolerant.

16. The second feature of objective truths noted in 10 (above) is that we must distinguish the truth of a belief from our justification for believing that it is true. This is fairly easy to see (much less complicated than what we covered in 11-15, above). One can have a true belief which is not sufficiently warranted. For example, prior to Copernicus someone might have had the belief that heliocentrism was true, but such a person might not have been justified in holding that belief. Moreover, one can have a justified belief which turns out not to be true. For example, many people prior to Copernicus had the justified belief that the Sun revolved around the Earth; but this belief turned out to be false.

17. Finally, we must distinguish between the truth of some statement expressing an objective truth and our ability to know that the statement is true. A statement may be true and we may have some justification for believing it, but we still may not know that the statement is true. Consider the following statement:

Goldbach's Conjecture =df., every even number greater than two can be written as the sum of two different primes. This statement may be true and, at this point, we have some justification for believing that it is true. However, we still do not know that it is true. So, we may have true beliefs which we do not know are true, and there may be (in fact, it is almost certain that there are) truths which we will never know and could never know.

18. What are some examples of candidate objectives truths? Consider the following:

Mathematical truths: 2+2=4.

Logical truths: _(A&_A).

Empirical truths: The sun is a star.

Metaphysical truths: God exists.

Moral truths: It is wrong for an instructor to give a student a failing grade in an academic course merely because the instructor dislikes the student's appearance. We'll leave a full discussion of moral truths to the Ethics course. But, it does look as though we are all committed to the existence of at least some objective moral truths (e.g., the one noted above, or "Murder is wrong," or "Torturing young children for one's own amusement is wrong"). That is, we are not inclined to accept someone's claim that these are mere matters of taste. Moreover, many of us are not inclined to accept the claim that the truth of these sentences is subjective--i.e., that their truth depends upon the preferences people happen to have (although, no doubt, most people do have preferences in accordance with these truths). Where people in our culture tend to start getting nervous about such moral truths is when they deal with what they perceive to be their private behaviors (e.g., what they do in their bedrooms). But, these are detail questions; the general position seems to be that we accept moral truths and that (at least some) moral truths are objective truths.

19. How is it possible for us to know these candidate truths? It seems clear that some of these truths are accessible by reason. Sometimes, though, people want to claim that it is science that gives us objective truths. One of our difficulties is that we live in a culture where science is seen as the primary/best source of (the best sort of) truth--so scientism characterizes our culture.

Scientism =df., the view that (1) only science gives us truth (a methodological claim), and/or (2) science gives us only the truth (a purity claim), and/or (3) science gives us the best kinds of truths (a worthiness claim), and/or (4) the truth is only what science can give us (a metaphysical claim). All four of these claims seem to be to be wrong. First, there seem to be many truths which I come to know by other than scientific means (even where "scientific means" is broadly construed): e.g., I come to know that my wife loves me (or that I love my wife) by other than scientific means (contra the methodological claim). Second, the history of science, littered with the wrecks of discarded theories, gives the lie to the purity claim. Third, it also seems to be false that science gives us the "best" truths. Consider the following argument. Assume (S): Science gives us the best truths. If (S) is true, what kind of truth is (S)? It seems that (S) should be one of the best truths; i.e., if we can make sense of the notion of "better" and "worse" truths, then intuitively (S) would seem to be one of the "better" ones and probably even among the "best" ones. (In general, it would seem that a statement which helps us to identify which statements are more valuable than others would be a statement that is valuable. By analogy, think of a test that helps us to determine the relative purity--and therefore value--of various samples of gold. Such a test would seem to be a valuable test, and it is valuable precisely because it helps us to detect degrees of value in other things.) But (S) does not seem to be the sort of truth that science could give us (what physics, chemistry, or biology experiment would yield this conclusion?); if it is a truth, it is a truth about science and not a truth of science. But then, according to (S), (S) would not be one of the best truths--which it seems that it should be. Fourth, it seems obvious that there are non-scientific truths--e.g., my wife is a wise and kind person--contra the metaphysical claim. So, we should allow for more than one way of coming to know objective truths and we should be wary of those who would elevate science to the position of being the only/best method for giving us (the best) objective truths.

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Copyright 1998 by David H. Calhoun and Brian B. Clayton.  This page last updated on May 28, 1998.