Thursday, March 28, 2013

Prescriptivism, Moral Injunctions, Imperatives and Rationality

In English, we have four types of sentences (with further subcategories). They are as follows:
(1) Statements
(a) indicative statements (declarative sentences)* = propositions
(b) subjunctives (wishes, requests, concessions, hypotheticals)
(2) Commands = Imperatives
(3) Questions
(4) Exclamations (e.g., exclamations, interjections).

* This includes negative statements too.
First, some remarks on grammar and the imperative.

The basic unit of logic and descriptive fact is a statement in the indicative mood – or (1.a) above – what we call the declarative sentence. In logic, this is also called a proposition. The proposition can be true or false. That is, it has truth value.

Next, there is the perplexing problem of whether sentences in the subjunctive mood can be true or false. The truth be told, I have never been able to find a straightforward, satisfactory answer to the question whether a subjunctive can be true or false! Let us leave this question unresolved.

What can be said is that a question, exclamation or command is never true or false, and all such sentences are fundamentally different grammatical categories from propositions.

For example, an imperative – category (2) above – is an order, instruction or command, such as “Go home!,” “Walk the dog!,” “Keep off the grass!” But these commands are not true or false.

One moral theory that has been advanced by philosophers is prescriptivism, a non-cognitivist view of ethics.

The leading advocate of prescriptivism was Richard M. Hare (1919–2002). When Hare came to formulate his meta-ethical theory of universal prescriptivism, he certainly saw a role for consequentialism.

According to prescriptivism, the moral statement is really a special kind of command (or imperative). Sentences with the word “ought” (“You ought not steal”) really conceal an imperative, a command.

The revolutionary conclusion of R. M. Hare is that a moral statement is not really a declarative sentence that can carry a truth value (that is, being either true or false). We are mistaken in thinking this. Moral statements are really just commands, and they urge action.

Many moral injunctions are really universalisable imperatives. That is, they invoke types or kinds and are addressed to the world at large, to people in general (Scruton 1994: 275).

And now the crucial point: by admitting that moral injunctions are imperatives and are neither true nor false, the prescriptivist is not abandoning rational thinking about what to do in the sense we normally call moral or ethical.

Actually, we can still have a rational debate about “moral” action! Moral injunctions follow the logic of imperatives (perhaps also inductive arguments about how to achieve teleological ends). It is a mistake to think you can only reason about declarative sentences, because imperatives do not necessarily lack a type of logic of their own. For example, imagine a set of books on a table. Someone says, “Carry all these books to the library!” If one considers any one particular book on the table, the command “take this particular book to the library!” follows from the first imperative (this example is based on the one in Scruton 1994: 275).

Hare contends that moral injunctions can be debated in rational argument (Scruton 1994: 276). Nor are moral injunctions necessarily subjective (Scruton 1994: 276).

For the prescriptivist, the point is that an “ought” statement is never logically entailed by any other descriptive fact or facts. The prescriptivist admits that Hume’s “is–ought” problem is unsolvable, but has successfully evaded it.

At this point, I depart from the strict views of prescriptivists, with other observations. What is the justification for any particular moral injunction? It needs to be rational.

One can construct inductive arguments to the effect that if one wants to achieve certain aims or ends, then certain actions should be followed. The conclusion of an inductive argument is never absolutely certain, and only ever probable. Therefore the fundamental claim of prescriptivism is not violated: no imperative or “ought” statement is strictly logically entailed by any inductive argument made to support it, in the way that the conclusion of a deductive argument logically and necessarily follows from its premises.

That is to say, rational discourse in ethics is in the same category as other forms of knowledge using inductive reasoning.

Prescriptivism does not satisfy many moral philosophers. Serious objections can be made. If what we think of as a moral judgements are not really true or false, it follows that moral error in the normal sense is impossible. At most, one could attack someone as urging action or performing action that lacks rational justification. Is that a satisfactory view of morality?

If I consult the general book I usually turn to when I want guidance on some general issue in philosophy, Roger Scruton’s Modern Philosophy: An Introduction and Survey (1994), I find that Scruton was unimpressed by prescriptivism. Perhaps that opinion is widespread amongst modern analytic philosophers.

Or maybe it is time to take a second look at prescriptivism, and see whether it can be developed in new ways!

To see where prescriptivism is located in a classification of ethical theories, we can provide a general classification of normative ethical theories here:

(1) Non-cognitivism
(1) Emotivism (Spinoza, Hume, C. L. Stevenson, A. J. Ayer)
(2) Prescriptivism (R. M. Hare)
(3) cognitivist expressivism (S. Blackburn; M. Timmons 1999; T. Horgan)

(2) Cognitivism
(i) Anti-realism
(a) Moral subjectivism
(b) Error theory
(ii) Moral realism
(a) Ethical naturalism
(1) Consequentialism/Utilitarianism
(2) Non-theological natural rights theory
(3) Thomism
(4) neo-Aristotelian ethical naturalism (P. Foot; R. Hursthouse)
(b) Ethical non-naturalism
(1) G. E. Moore ethical intuitionism/agathistic consequentialism
(2) Platonist ethics
(3) divine command ethics
(4) Kantian ethics

Scruton, R. 1994. Modern Philosophy: An Introduction and Survey. Penguin Books, London.

Baggini, Julian and Gareth Southwell. 2012. Philosophy: Key Themes (2nd edn.). Palgrave Macmillan, Basingstoke.


  1. You want to be careful in general about philosophy: philosophers are interested in good questions, not answers. An answered question is no question at all anymore.

    Two questions stand out. First, what does it mean for a moral prescription to be rational?

    Understanding rationality in the context of ethics is especially problematic, since on many ethical accounts, our desires are in some sense relevant. However, is it rational to do something just because you want to? For example, if I just want to go see a movie, is it rational to go see a movie? Or do I need to have an objective reason to go see a movie to make it rational to actually see the movie? Both accounts are problematic especially in ethics.

    Second, what does it mean for a (meta-)ethical system to be satisfactory? A satisfactory theory in the natural, scientific sense is just one that compactly organizes and systematizes some set of observable facts. However, if we allow a (meta-) ethical non-naturalism, then this definition of satisfactory would obviously be incomplete. However, if we abandon the natural, scientific sense, it is not immediately obvious that we can construct even a semi-rigorous definition of satisfactory, and we would have to rely on a purely subjective sense.

  2. "In English, we have four types of sentences (with further subcategories)..."

    There's a fifth: jokes. Entirely different type of sentence. And VERY important for how language actually functions.

    1. That is an interesting view!

      And what is the evolutionary origin of humour? (if there is one). You have got me thinking...

    2. Lo and behold, here is a talk by Daniel Dennett no less on the origin and purpose of humor:

  3. Interesting thoughts Lord Keynes. Real deep stuff,that need to be
    carefully readen. One of my favourite´s that dealed with those questions, was Georg Henrik von Wright, who succeeded Ludwig Wittgenstein as professor at the University of Cambridge.His writings on moral philosophy are a interesting attempt to melt together analytic philosophy and philosophical logic in the Anglo-American (, philosophy of action, philosophy of language, philosophy of mind) with the thoughts Jürgen Habermas and the Frankfurt school's reflections about modern Rationality and other "contiental" philosophers.