Assessing normative claims

Arguments often have normative conclusions. That is, they make claims about what we should or shouldn’t do, or about what ought to be the case. To be valid or forceful, an argument with a normative conclusion must have a normative premise (a premise with a “should” or an “ought” in it).

To assess the soundness of such arguments we need to assess the truth of normative claims.

Moral claims are one common type of normative claim. Some people think that  it is not possible to assign truth values to moral claims. There are severe disadvantages to such a view. If moral claims cannot be true or false, then there are no actions which are not permissible. Most people don’t want to accept that. So, if there are no moral truths, then you cannot say that

Slavery is wrong

is true. Nor could you say that

It is okay to torture babies for fun

is false.

In fact, if moral claims cannot be true or false, we would never be able to assess an argument which included a moral claim as a good argument. This is unsatisfactory. We need to be able to assess moral arguments, and to establish that some actions are impermissible, and some are good, and so forth.

In this course, we accept that moral claims, and other normative claims, can be true or false.

That does not mean that it is always easy to know the truth value of a normative claim. Like other propositions some are easier to evaluate than others.

Suppose someone gives the following argument:

Smoking can cause cancer, and it’s bad for your lungs. This means smoking is bad for your health, and therefore you should stop smoking.

When we reconstruct this argument, we’ll end up with a connecting premise that says something like

If smoking is bad for your health, then you should stop smoking.

Is this true?

Your first reaction might be that it’s true. But we should think carefully. Note that the more general claim “If something is bad for your health then you should not do it” is not true. There are exceptions. For example, fire-fighting is bad for your health. Fire-fighters regularly suffer burns, and smoke inhalation, and it’s a stressful job. All these things are bad for the health of fire-fighters. But that doesn’t mean we shouldn’t have fire-fighters. Or, being a defensive tackle on an American Football team is bad for one’s health. They have a high risk of serious concussion and other injuries. But it’s not clear that it follows that all defensive tackles should immediately quit their jobs.

So the statement “if something is bad for your health then you should not do it” is not true. Is the smoking-specific version of it true?

When you ask someone why they smoke, a variety of reasons are given. It brings pleasure, it’s a social activity (people who smoke often do so with other people), it’s a useful way to unwind, and so forth. There’s not a greater benefit to society the way there is with fire-fighting. Nor are there the financial rewards and the personal satisfaction of being a good defensive end. If the people who currently smoke ceased smoking, there wouldn’t be the drawback for society that there would be if fire-fighters all quit their jobs. Nor would any smokers lose their livelihood as a result.

We can also note that there are other ways to achieve the benefits of smoking: there are other ways to relax, and other ways to be social. Could you vape with your friends instead? (Whether you can may depend a bit on your friends.) Vaping is healthier than smoking, but can be done in many of the same circumstances, and delivers nicotine, so it can accomplish many (though presumably not all) of the same things as smoking.

We can also note that the claim made in “If smoking is bad for your health, then you should stop smoking” is not a claim about what you will do, but about what you should do. Given that, and that vaping, which is healthier, can achieve many of the same things, I’m willing to accept that “If smoking is bad for your health, then you should stop smoking” is true. I only accept it, however, in the smoking case. I still hold that “If something is unhealthy then you shouldn’t do it” is false.

This gives you some idea of what should be considered when assessing the truth of a statement.

We can now insert the statement back into the argument.

P1) Smoking significantly increases your risk of getting cancer.
P2) Smoking is harmful to your lungs.
P3) Anything that significantly increases your risk of getting cancer and is harmful to your lungs is bad for your health.
                                                   
C1) Smoking is bad for your health.
P4) If smoking is bad for your health, then you should stop smoking.
                                                   
C) You should stop smoking.

P4 was the most controversial premise here. I haven’t specifically evaluated the others, but they are true. Given that P4 is also true, this argument is sound.