Honors Ethics

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Tuesday, 09-05-17: Introduction & Logic Review


Today we prepared to launch into essentially the mid-point of the semester, due largely to constraints on our time caused by necessary preparations for the Ethics Bowl. That is, what would ordinarly be the first half of the semester will be pushed back to after the Ethics Bowl. What this means is that I have to skip a great deal of introductory material, including most notably our discussion and subsequent rejection of moral relativism and our discussion and subsequent rejection of moral theology.

Nevertheless, some introductory discussion is in order, and to motivate that discussion we consider two cases from last year's regional ethics bowl: "Body Dysmorphic Disorder" and "Legalize It All". The point of taking up cases on the very first day, unusual a move as it may be for an introductory ethics course, was to get started on the difficult problem of unpacking the moral dilemmas implied by these sorts of difficult cases. It was also to help frame a difficult question: What could be the point of an ethics class, really?

That is, the thought that we shall study ethics begs an important question:

Can ethics be taught?

This is a surprisingly difficult question.

On the one hand, people will say that ethics is about not hurting other people and doing good things; there's nothing especially puzzling or challenging about that, so we really shouldn't need to spend time talking about ethics.

These people are in the 'Ethics is Obvious' camp. According to the Ethics-is-Obvious camp, ethics cannot be taught in the same sense that the fact that grass is green cannot be taught; just looking is enough to know the truth, and if you don't know what it is to be green, no amount of explaining will help.

On the other hand, people will say that ethics is about whatever a person happens to believe she ought to do. There's no truth to ethics. It's just whatever you believe, or maybe it's just whatever you were raised to believe. There's no point in talking about ethics since there's nothing to be decided; people believe what they believe, end of story.

These people are in the 'Ethics is Mysterious' camp. According to the Ethics-is-Mysterious camp, ethics cannot be taught in the same sense that one cannot be taught what one believes.

Either way, there's seems to be little point in spending time talking about ethics.

But let's not be too hasty.

What if the two camps are mistaken? Suppose there is a middle camp. Suppose there are some situations where it really isn't obvious what we ought to do, but there is a fact of the matter and we are able to figure it out if we roll up our sleeves and get to work.

I'm in this middle camp.

  • I don't think it's obvious that capital punishment is morally permissible, but I do think we can discover the truth.
  • I don't think it's obvious that colleges and universities shouldn't be allowed to use race as part of admission's standards, but I do think there are reasons for and against that we ought to study very carefully.
  • I don't think it's obvious that conducting experiments on animals is morally permissible, but I do think the debate will, eventually, lead us to the truth.
  • I don't think it's obvious that cloning a human being is morally wrong, but I do think there is a fact about whether it's right or wrong--a fact that is accessible to us.

Those of us in the middle camp have learned that answers aren't always easy when it comes to moral questions; yet we are confident that the answers exist and are accessible to us.

Because we are rational animals, we have the capacity to arrive at the truth of moral matters; because we are rational animals, the truth of moral matters sometimes escapes us.

It seems to me Plato got it right: Ethics is about nothing less than how we ought to live our lives, and this is certainly something about which we can reason.

To be sure, this is not yet an argument. The argument I plan on making to justify the view that even hard ethical cases can be solved provided we are diligent, careful, and smart will take most of the semester to make. It may be that you won't find the argument convincing, although I hope some will. Yet even if you reject the argument, you will have gained a much deeper understanding of moral matters in the process.

Now, much of what we do this semester depends on logic. Most of you had Honors last semester; some did not. For those of you who had Honors Logic, the following is a bare-bones review. For those who did not, please note that I do not expect, require, demand, or even believe that you understand every concept from today's lecture. The most important concept we shall use--and the most difficult to grasp--is the concept of validity or, equivalently, entailment.

A set of propositions S, we say, entails a proposition P if, and only if, (iff) it is impossible for P to be false when all the members of S are true. Equivalently, we say that an argument is valid iff its premises entail its conclusion. Thus, for example,

Example Argument
  1 All whales are mammals.  
  2 Willy is a whale.  
3 Willy is a mammal. 1&2

This is a valid argument: (1) and (2) together entail (3). Willy could not fail to be a whale if he is a whale and all whales are mammals. What if he were not a whale, however? Suppose 'Willy' is the name of your next door neighbor. Then Willy is not a whale, but it just so happens he's a mammal. What if 'Willy' were the name of your pet snake? Then the conclusion would be false, but not because it is false that he is a whale.

I grant that this can all be rather confusing. There are a few facts about arguments which are crucial. If you don't understand them at first, you should at least memorize them.

  1. In a valid argument, the conclusion must be true if the premises are all true.
  2. If one or more of the premises in a valid argument are false, it does not follow that the conclusion is false. The conclusion may still be true; the argument just doesn't give us any reason for thinking that it is true.
  3. If the conclusion of a valid argument is false, however, at least one of the premises must be false.
  4. A valid argument may have all true premises and (necessarily) a true conclusion, a false conclusion and (necessarily) one or more false premises, false premises and a false conclusion, or false premises and a true conclusion.
  5. The only situation in which the actual truth or falsity of the propositions in an argument tell us anything at all about the validity of the argument is when the premises are all true but the conclusion is false: we then know that the argument is invalid. The validity of an argument is completely independent of the actual truth or falsity of the propositions in the argument in the sense that one can never find out whether the argument is valid based on the actual truth or falsity of the propositions in the argument.
  6. An argument is valid if it has the form of a valid argument; validity is a formal or syntactic feature of arguments.
  7. If an argument is sound, then we know that its conclusion is true.
  8. If a deductive argument is unsound, we know that it is either invalid, or it has at least one false premise.
  9. Critically assessing arguments requires that we first find out whether or not the argument is valid and then find out whether or not the premises are all true. If the argument is invalid or has at least one false premise, then it follows that we have no reason to think that the conclusion is true; it does not follow that we have any reason for thinking that the conclusion is false.

There are other facts, of course, but these are the most important ones for you to grasp at this stage.

To be sure, arguments as we encounter them in the wild, as it were, are never cleanly presented in numbered lines with the conclusion and any sub-conclusions clearly labeled as such. Instead we meet arguments where important premises are left out and conclusions can even go unstated. This can frustrate careful reading, to say the least

Part of our job, then, is to learn how to assess arguments as we come across them. To guide you, I've provided a handout on the process of Extraction, Explanation, and Evaluation whereby we strive to ascertain once and for all the cogency of an argument. Since there is a lengthy handout on this, I won't go further into the specifics here. Suffice it to say that the process is tedious and difficult, but it is enormously important for all that if our goal is to find the truth.

The point of all this foundational work in logic is to establish a series of standards for the critical evaluation of moral normative theories. The standards are minimal in the sense that a theory which fails them is clearly false, while a theory which passes them might be true, but it could also be false. Thus, the Standards of Evaluation are used to exclude theories which do not have a chance of being true.

The analogy with science is important. Just as scientific theories consist of a core set of propositions (usually called laws in science or axioms in mathematics), which jointly entail descriptive propositions (often called testable hypotheses in science or theorems in mathematics), moral theories consist of a core set of propositions called principles which entail prescriptive propositions.

Now, as we've seen, validity is a curious relation. We say that a set of propositions S entails a proposition P if, and only if (iff) it is impossible for all the propositions s in S to be true and P false at the same time. Put another way, if S entails P and P is false, then at least one of the propositions s in S must also be false. Yet if P is true (and S entails P), you cannot conclude every s in S is true! All that is ruled out by validity (entailment, properly speaking) is that P be false when every s in S is true. P can be true and S entail P even though every s in S is false.

Consider a mathematical theory like Euclidean Geometry, wherein a finite set of assumed--nominally, self-evident--propositions called the axioms entail all the theorems of the theory. Since the axioms themselves cannot be further justified (else we would simply have another set of axioms entailing them, and the whole structure repeats!), we simply take them to be true. As any historian of mathematics will recognize from the parallel line postulate of euclidean geometry, its rejection, and the emergence of non-euclidean geometries, such assumptions can be problematic.

As with mathematical theories, so with physical, or scientific, theories: A finite set of propositions, called in science natural laws entail indefinitely many propositions, collectively called the hypotheses of the theory. Thus since the natural laws are presumably true (else they would not be laws of nature), and experiments are intended to falsify hypotheses, we seem to have a bit of a conundrum in virtue of the fact that the laws entail the hypotheses. That is, the hypotheses cannot be false if the laws are all true, since the latter entail the former.

So, what gives?

In light of an experimentally rejected hypothesis which has been entailed by the natural laws, at least one of the natural laws must be false given the entailment relation between them. We are lead inexorably to embrace the old adage--since Karl Popper, at least--that science never proves anything true, it only proves false. An experiment that fails to falsify, therefore, cannot be taken to prove true. At most, we have a confirming instance, which tells us almost nothing.

Exactly the same point made of scientific theories applies to ethical theories, as we'll see when next time we take up Utilitarianism.