Teaching & Learning Guide for: Belief-Desire Explanation



This guide accompanies the following article: Nikolaj Nottelmann, ‘Belief-Desire Explanation’. Philosophy Compass Vol/Iss (2011): 1–10. doi: 10.1111/j.1747-9991.2011.00446.x

Author’s Introduction

“Belief-desire explanation” is short-hand for a type of action explanation that appeals to a set of the agent’s mental states consisting of 1. Her desire to ψ and 2. Her belief that, were she to φ, she would promote her ψ-ing. Here, to ψ could be to eat an ice cream, and to φ could be to walk to the ice cream vendor. Adherents of belief-desire explanation, often labelled “Humeans”, standardly assume that appeals to such belief-desire pairs sufficiently explain many human and animal actions, and also that all actions are explainable thus, at least in so far as they are guided by the agent’s intentions. Humeans take their lead from David Hume’s famous dictum that “Reason...is only to be the slave of the passions, and can never pretend to any other office than to serve and obey them.” In its original context, this passage from the Treatise is naturally taken to convey the thesis that mental states subservient to epistemic rationality – such as beliefs – are never in themselves sufficient to motivate action. Thus, an appeal to an agent’s beliefs is never in itself sufficient to lay bare her motivations and explain her actions, but must be supplemented by an appeal to “passions” such as desires. Many philosophers, so-called Anti-Humeans, have sharply disagreed. Some have pointed to certain beliefs with alleged motivational force in isolation from desires, most commonly evaluative beliefs. Others have argued that belief-desire psychology fails to cut up mental space in a way fruitful to action explanation. Instead, only appeals to other types of mental state will adequately explain many types of intentional action. The debate for and against Humeanism is a highly complex one, which is likely to persist along with any general interest in the theory of action explanation.

Author Recommends

Hume, David. A Treatise of Human Nature. 2nd ed. Edited and with an Analytical Index, by L. A. Selby-Bigge. Oxford: Oxford University Press, 1978.

Part III. Sect. III. (Of the influencing motives of the will) of the Treatise is the classical source of the Humean view. Any in-depth understanding of contemporary Humeanism must take it as its starting point.

Stroud, Barry. Hume. London: Routledge, 1977.

This is an excellent introductory text. Chap. VII (Action, Reason, and Passion) treats on Humeanism and the key part of the Treatise listed above.

Smith, Michael. ‘The Humean Theory of Motivation.’Mind 96.381 (1987): 36–61.

This is an authoritative modern account of Humeanism. Even if a bit imprecise in some regards (see the root paper for this TLG), the text is lucidly written and nicely captures the structure of the debate over Humeanism.

Schaefer-Landau, Russ. Moral Realism. A Defence. Oxford: Clarendon Press, 2003.

Chapt. 5 (Motivational Humeanism) contains another fine, more recent, introduction to Humeanism and the typical arguments for and against it. This introduction is particularly recommendable in virtue of its clarity and comprehensiveness.

Ratcliffe, Matthew. Rethinking Commonsense Psychology. A Critique of Folk Psychology, Theory of Mind and Simulation. New York: Palgrave Macmillan, 2007.

This monograph treats on a very wide number of subjects pertaining to action explanation and harbours many highly controversial theses. Still, it is a refreshing eye-opener re the immense complexity of the topic of action explanation and the great variety of such explanations in our folk practices. On my view Ratcliffe makes plausible the view that neither our folk practices nor our scientific practices single out a unique (or even a few) model(s) of action explanation as the only appropriate one(s). Rather our practices of action explanation constitute a rather motley family. The consequence of this to the debates over Humeanism is obvious: The combatants must get clear on the exact models of action explanation within which they discuss the place of belief-desire references instead of pretending to fight over action explanation in general.

Gendler, Tamar Szabó. ‘Alief and Belief.’Journal of Philosophy 105 (2008): 634–63.

This paper, together with Gendler’s contemporary sister paper ‘Alief in Action (and Reaction)’, is an engaging proponent of the view that belief-desire psychology and its associated practice of Human action explanations gets psychological reality radically wrong. Gendler presents a number of cases where, allegedly, relevant human actions are only explicable by appeal to a type of mental state, which Gendler dubs “alief”. Aliefs are neither beliefs nor desires; but share certain characteristics with both.

Online Materials







Sample Syllabus

Week I: David Hume’s view

Hume, Treatise, Part III. Sect III.

Stroud: Hume, Chapt. VII.

Week II: Modern Humeanism

Smith, ‘The Humean Theory of Motivation’.

Nottelmann, ‘Belief-Desire Explanation’.

Week III: Modern Humeanism continued: The Dialectics of the Debate

Schaefer-Landau, ‘Motivational Humeanism’ (Moral Realism. Chapt. 5).

Week IV: Intention, Agency and Causation

Davidson, Donald. ‘Actions, Reasons, and Causes’ & ‘Freedom to Act’, both in: Essays on Actions and Events. Oxford: Clarendon Press, 1980.

Week V: Modern Anti-Humeanism, The Neo-Kantian Version

Scanlon, T. M. What we Owe to Each Other. Cambridge, MA: The Belknap Press, 1998, Chapt. 1. ‘Reasons’.

Week VI: Modern Anti-Humeanism, The Cognitive Science Version

Gendler, Tamar Szabó. ‘Alief and Belief’, supplemented with excerpts of her ‘Alief in Action (and Reaction)’. Mind and Language 23.5 (2008): 552–85.

Focus Questions

  • 1 Which kinds of explanation do belief-desire explanations belong to (causal, rationalizing, intentional, instrumental etc.)?
  • 2 In so far as belief-desire explanations provide causal explanation of action, how are we to understand the causal nexus between belief-desire pairs and successful agency?
  • 3 How are we to understand the notions of belief and desire as appealed to in belief-desire explanations? Are they even conceptually distinct from the concept of a belief-desire explanation of human action?
  • 4 May evaluative judgments such as moral judgments motivate and/or rationalize action in isolation from accompanying distinct co-native states of the agent?
  • 5 Are certain types of intentional action better explained with sole reference to mental states different from belief as well as desire (e.g. Gendlerian “aliefs”)?