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Internalism and Externalism in Ethics


Among the various uses of the term internalism in ethics, there are two that are central and importantly different. In the following entry, these two uses will be distinguished as judgment internalism and reason internalism.

Judgment Internalism

Judgment internalism is the view that moral judgments can be sufficient to motivate actions. Motivation is internal to morality. Externalists, by contrast, hold that the motivation to act morally is supplied by motives that are only contingently related to moral judgments. Internalism is thus opposed to the view that we need to appeal to special motives in order to explain compliance with moral demands, such as sympathy, as well as to a Hobbesian outlook claiming that the motivation to act is always self-interested, and that the motivation to act morally must therefore be self-interested, too. Internalism in this sense has been defended by Thomas Nagel (1970), John McDowell (1978), Christine Korsgaard (1986), and possibly by Immanuel Kant (1785).

One of the first to introduce the term in this sense was William Frankena (1958) who is critical of internalism. Externalismthe view that moral judgments as such cannot motivate moral actionshas few explicit defenders. However, John Stuart Mill (1861) claimed that we should distinguish sharply between the 'proof' of the moral principle (the principle of utility, as he sees it) and its 'sanctions.' While it can be demonstrated to anyone that an action is morally wrong if it violates the principle of utility, the motivation to act in accordance with the principle will be present only in those who received an appropriate education.

One response to judgment internalism is error theory (Mackie 1977). On the level of semantics, internalists have it right: Moral judgments involve an attempt to refer to properties that exist independently of a person's desires, but that are capable of motivating him or her. Thus, on the one hand, those properties must be features of the world as it is independently of our responses to it. But, on the other hand, we necessarily respond to them in certain ways. This combination of claims is, according to Mackie, ontologically speaking, 'queer:' It requires that moral properties be primary and secondary properties at the same time. But there can be no such properties. Therefore, all our moral judgments are false (for a critical discussion of J.L. Mackie's argument, see McDowell [1985]).

Reason Internalism

Yet there is a different use of the terms internalism and externalism that in effect reverses the one sketched above. Bernard Williams in his influential essay Internal and External Reasons (1980) defends the view that all practical reasons are internal reasons. By internal he means that they are related to a person's given desiresto the elements of his or her subjective motivational set. This Hume-inspired view is based on an explanation of motivation in terms of desires as a distinct kind of psychological state.

Practical reasons are potentially both explanatory and justificatory: They determine what a person should do, but also explain his or her actions (if he or she acts for those reasons). But as explanation must appeal to an agent's motives (or desires), reasons have to be suitably linked to those. Desires, in turn, are not (ultimately) the product of reasons. Therefore, in order to be explanatorily relevant, a person's reasons must be based on his or her given desires. A person has a reason to ϕ, if he or she can reach the conclusion to ϕ by a sound deliberative route starting from his or her given desires (Williams 1989).

Desires, Williams explains, need not be conceived narrowly. The term applies to a whole array of states of a very different kind comprising a person's projects, commitments, and loyalties. Desire is simply a term of art that can be used to refer to all motivationally relevant attitudes. It follows that a person has reason to act in a certain way only if he or she happens to have an appropriate desire: a desire that will be satisfied if he or she acts accordingly, provided the desire is not based on false belief and formed on the basis of correct information about the relevant facts. Therefore a person's reasons do not exist independently of his or her psychological states.

This view is at odds with the normal understanding of moral reasons, and of practical reasons more generally. We tend to interpret at least some reason statements as referring to how things are in the world (independently of the agent's attitude toward them). They are thus external reasons, according to Williams's terminology: reasons that are independent of a person's psychological states. In interpreting reason statements as referring to external reasons, Williams claims, we are mistaken because external reasons are incapable of explaining a person's actions (for an earlier, yet different defense of a similar view, see Davidson [1963]).

Williams's defense of internalism led to an intense and continuing debate (see Hooker [1987], Smith [1995], Millgram [1996], FitzPatrick [2004]). McDowell (1995) replied that Williams may well be right thinking that if reasons can be external, then not everyone is capable of being motivated by practical reasons that apply to him or her. But the externalist is not committed to thinking that they can. The externalist's crucial claim is that reasons exist independently of motivesnot that they can motivate anyone independently of what his or her motives happen to be. Is the externalist committed to denying Williams's claim that practical reasons are both justificatory and explanatory then? According to McDowell, he or she is not. Those who are motivated by reasons may not be so motivated by a desire whose existence is independent of the reason.

McDowell suggests an Aristotelian alternative to Williams's Humean view: The capacity of being motivated in the right way is a matter of moral upbringing. But moral upbringing is (in part) the ability to be motivated by moral reasons. The moral person is one who responds to his or her perception of the morally salient features of the his or her situation. Thus McDowell can agree with Williams that practical reasons are both justificatory and explanatory, but denies that explanation must appeal to desires that exist independently of reasons. Reasons exist independently of desires, and they can motivate independently of themat least those who have been brought up in the right way.

Various versions of reason externalism have been proposed in recent years (see Dancy [2000], Parfit [1997], Raz [1999], Scanlon [1998]). Korsgaard (1986 and 1996) defends a version that is stronger than the one proposed by McDowell: She claims that a reason can motivate a person insofar as he or she is rational (independently of given motives). According to her, being rational is the ability to respond to reason, and we all have that ability (perhaps to a lesser or higher degree). Thus there is no emphasis on moral upbringing in Korsgaard's account of motivation.

Against this, Michael Smith (1987) provides an a priori argument for internalism, oras he puts itthe Humean theory of motivation. Smith develops Hume's view that beliefs and desires are distinct psychological states, distinguishing them by their different direction of fit. Beliefs aim to represent the world as it is, whereas desires are an agent's dispositions to change the world in such a way that it fits with the desire. Beliefs have a mind-to-world and desires a world-to-mind direction of fit. Only states with the right direction of fit (i.e., desires) can motivate. Beliefs as such cannot. If we are to understand value judgments as beliefs (as Smith thinks we should) they will not be sufficient to explain actions (Smith 1994). This argument gave rise to an ongoing discussion (Wallace 1990; Velleman 1992).

The two uses of internalism can be seen as related: The older tradition of judgment internalism identifies internalism with the claim that moral judgments as such are capable of explaining actions. This claim, however, bears some similarity to Williams's claim that practical reasons are both justificatory and motivating. The main difference is that judgment internalism is confined to moral judgments, whereas Williams is concerned with practical reasons more generally (a further difference is that reason internalists are not committed to accepting that practical reasons are, at least in part, judgments; for the significance of this difference see Dancy [2000]).

Yet, according to Williams, put together with some version of the Humean theory of motivation, the claim that practical reasons are both explanatory and justificatory leads to the conclusion that reasons must be based on desires, which is the view that he calls internalism: reason internalism. Thus, roughly, judgment internalism labels one of the premises of Williams's argument internalism, whereas Williams himself uses the term to refer to its conclusion. The focus of disagreement is then on the Humean theory of motivation, which divides the two approaches.

See also Error Theory of Ethics; Hume, David; Kant, Immanuel; Mackie, John Leslie; McDowell, John; Metaethics; Mill, John Stuart; Moral Motivation; Nagel, Thomas; Normativity; Response-Dependence Theories; Williams, Bernard.


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Ulrike Heuer (2005)

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