How to Derive “Ought” from “Is”
Sorry to be a bit technical this time, but I want to dispel a pernicious misconception that has haunted western philosophy for nearly three hundred years, the idea that you cannot derive “ought” statements from “is” statements. In fact you can, quite easily.
In Book III of his Treatise of Human Nature, published in 1740, David Hume asserts that normative statements (saying that you ought or ought not to do something) cannot be derived from descriptive statements (saying that something is or is not the case).(1) For instance, from the mere fact that you had to have parents in order to exist, you cannot logically deduce that you ought to honor your father and mother. This has been known ever since as the “is-ought” problem. But actually it is easy to derive “ought” from “is”. The general form is what Kant calls a hypothetical imperative. Here is an example:
If you want to get along with people, then you ought to be honest and friendly.
We can spell this out logically as follows:
Premise: People who are honest and friendly get along with other people.
Premise: You want to get along with other people.
Conclusion: You ought to be honest and friendly.(2)
That’s not hard, right? We have just derived “ought” from “is” in a very easy and straightforward way. So why has this become such a bugbear over the last three centuries of moral philosophy?
It is because people – Hume included – confuse two meanings of “ought”: what is good and what is right. And then they get all hung up trying to figure out what is right when they would be much better off figuring out what is good.(3)
People who think in terms of what’s good think about the effects of what they do, focusing on what is beneficial and what is harmful. People who think in terms of what’s right think about duty and what conforms to moral rules. The two sometimes overlap, but they are really different concepts, and it is not helpful to mix them. And it is certainly not helpful to focus excessively on what is right.
The pure form of the rightness paradigm says we should not consider the consequences of what we do at all, but only whether our actions conform to moral law. Kant, the most famous proponent of this view, said we have a moral duty always to tell the truth. Someone objected, saying that if a murderer were pursuing our friend and our friend hid in a house, we should lie and tell the murderer that our friend went somewhere else. Kant said no, we should tell the truth even if it means our friend’s death!(4)
We instinctively think that’s wrong. And that very instinct reveals something important about our notion of right and wrong: its source in our moral intuitions.
Most of our moral decisions are not reasoned judgments. Instead, they are gut reactions, made automatically by hunch, habit or intuition. You did not have to ponder the matter to know that Kant is being really weird when he says we should tell the truth to the murderer. You just knew that it does not feel right. That feeling of discomfort – a moral intuition – is the source of our notion of rightness.
We are hard-wired to have moral intuitions, for good evolutionary reasons, Biologically, humans are ultra-social animals who live and thrive in groups of people and who cannot survive in isolation. No wonder we are highly attuned to social concerns: who is playing fair and who is cheating; who needs our help and who can help us; who outranks us and who we outrank in the social hierarchy. We make snap judgments in those areas all the time because our brains have evolved to do so. Those who survived better in groups had more offspring than those who didn’t, and we are their progeny.
These judgments take place below the level of consciousness. We don’t pay attention to how we make them; they just pop up. Phenomenologically, people’s behavior just appears appealing or repulsive, praiseworthy or blameworthy. And we take our judgments to be universal, applicable without exception. (Why? because those who stopped to question the group norms did not get along as well as those who didn’t. Hence, they had fewer offspring, just like those who stopped to think about whether they should flee a menacing animal.)
So the sense of right and wrong, including the sense that moral rules are universal, is a result of the evolution of humans in groups.
This explanation is descriptive, not prescriptive. It tells us where the moral sense comes from, but not what to do in any given situation nor what kind of person to try to become. And obviously it does not automatically make the moral rules of our culture the right ones. (This is the proper application of the is-ought dichotomy, by the way. That something is the case does not make it right. But it can easily make it good or bad.)
We certainly do have moral intuitions, but we still have to figure whether or not it makes sense to act on them. Sometimes we actually get to think about what to do, particularly when the instinctive rules conflict. What if it is not a murderer who is pursuing our friend but someone who has a legitimate complaint, that our friend owes him money? Shall we lie to protect our friend or tell the truth to allow a debt to be settled?
In making that decision we need to look at more than moral rules. We need to look at the consequences of our proposed actions and whether we expect them to have a good effect. To accept blindly our sense of morality without examining it is unworthy of an excellent human being.
(1) The entire text of A Treatise of Human Nature is available on line. URL = http://www.class.uidaho.edu/mickelsen/ToC/hume%20treatise%20ToC.htm as of 8 October 2010. The idea cited is at the very end of Book III, Part I, Section I.
(2) For those interested in the details, this argument is based on the logical form called modus ponens:
A implies B
A is true
therefore B is true
The ethical form replaces the second premise with an assertion about desire or intention instead of about truth and concludes with an imperative, or at least a recommendation:
A implies B
One desires B
therefore one ought to do A
Instead of asserting that A is true and deriving B, we say that we want B to be true, and hence we should do what we can to make A true.
(3) For an account of the history of these ideas, see Edel, Abraham, “Right and Good,” on-line publication, URL = http://www.bmeacham.com/whatswhat/OP/Edel_RightAndGood.htm as of 11 October 2010. See also my paper “The Good and the Right,” URL = http://www.bmeacham.com/whatswhat/GoodAndRight.html.
(4) Kant, Immanuel, “On A Supposed Right To Lie Because of Philanthropic Concerns.” On-line publication (PDF), URL = http://philosophyfaculty.ucsd.edu/faculty/rarneson/courses/KANTsupposedRightToLie.pdf as of 19 October 2010. Unfortunately, the translator is not listed.