Generative Economics


Generative Economics



Darwin’s theory of evolution includes two generative components: mutation and natural selection. Mutation generates genetic variants and hence phenotypes; natural selection operates on these to produce differential survival. Neither of these generative processes involves intention or intelligence. Thus we have biological novelty without intentional intelligent design. Both processes are blind and driven by non-mental causes. We have creativity without a creator. But Darwin also recognized what he calls artificial selection, as with the selective breeding of dogs (or horses and flowers). Here human beings intentionally direct the course of evolution according to their own preferences, producing dog breeds that would not arise by natural selection. This is not selection by nature but selection by human design and desire. Of course, the process of generation is still natural not artificial: dog breeders rely on the genes to generate dog variants. They don’t make poodles from scratch; they just interbreed dogs and let the genes do their work. So here we have a case of natural generation and artificial selection to be added to the far more common case of natural generation and natural selection. Dog breeders don’t even know how to generate dog variants artificially; they depend upon natural reproduction.

In principle there could be artificial generation combined with natural selection: a type of intelligence creates an organism and then turns it loose in the world to the tender mercies of nature. You could genetically engineer organisms and then let nature select the good from the bad. In effect that is what happens with many human artifacts: they are intelligently created but left for nature mindlessly to destroy or preserve (as with architectural ruins and plastic bags). What about artificial design combined with artificial selection? Can there be intelligently created entities that are then intelligently selected? Of course there can: machines created by humans and selected by humans to be used as they see fit. Motorcars are propagated by these two modes of generation: first they are designed and manufactured by the use of intelligence; then they are bought and sold in the marketplace by a process of intelligent selection, intentionally and consciously. So there are four logical possibilities in all: natural generation and natural selection, natural generation and artificial selection, artificial generation and natural selection, and artificial generation and artificial selection. Entities can come into existence and reproduce (or be reproduced) by any of these four methods.

There is something strange in Darwin’s terminology, because so-called artificial selection is itself a natural process. The mind is natural and it is what directs selective breeding; there is nothing super-natural going on here.[1]Bees select flowers and hence direct the course of flower evolution: this is not “artificial”. When humans selectively breed animals for their own purposes this is an aspect of their species-specific nature. It would be better to speak of intentional intelligent selection versus selection that is neither. For intelligence is part of nature too. Still, we can keep the terminology for convenience. The question I am interested in is the nature of economic activity; and what I want to maintain is that economic activity is continuous with biology. It is just another form of biological generation. Now it is true that (so far as I know) other animals don’t engage in economic activity, though it would serve my purpose if they did; but that doesn’t prevent us from imagining such activity in animals. So suppose we encountered a species of bird that manufactures nests that it exchanges with other birds for food. Instead of just building a nest for its own use, it builds nests “for sale”. This has become part of its genetic make-up, as much as nest-building itself. We can think of it as instinctual and automatic, like birdsong, and not as reflective and flexible: birds that exchanged nests for food in the past (as a result of some mutation) did better than birds that kept their nests to themselves. Thus a primitive bird economy develops. In such a case we would say that the entire process is part of the bird’s biological endowment. The “buyer” birds would select nests according to their own criteria and a form of competition might develop, which would lead to a selection process. In just such a way human commerce might have originated: humans capable of exchange do better than humans incapable of it. This would also be as biological as digestion and sexual reproduction, whatever the later elaborations (banks, money). It is a form of social behavior rooted in biological imperatives.

So there are two principles of generation at work here: generating the nests and their being selected. Both are “artificial” in Darwin’s strained sense, since they involved goal-directed action. The bird makes the nest not its genes and other birds do the selecting not brute nature. But this doesn’t exclude the phenomenon from the realm of biology. Or again, consider those ants that enslave other ant populations: these “brood parasites” seize the eggs of other ants and bring them back to their own nest where they carry out the work of their “slave-owners”.  Again, I don’t know of any documented cases of ants that then trade their slaves with other ant slave-owners, but the idea is not beyond reason. What if we encountered an ant species that did just that, perhaps because they were better raiders than their potential trading partners? The “buyers” exchange food for slaves, which they find a bargain. This would be an entirely biological arrangement, not introducing any new non-natural principle into biology. Some ants are natural-born slave-traders! No doubt this is deplorable of them, but it is biologically possible. They thus have a nice little economy going here—a system of exchange trading one sort of good for another.

I don’t think it is farfetched to suggest that human economies are analogous. Perhaps they even arose from some such primitive beginnings way back with our ancient ancestors in Africa. In any case, we can say that human productivity and the capacity for economic exchange are part of our biological nature. It turns out that the biological realm includes more than just natural generation and natural selection (in Darwin’s restricted sense); it includes the kind of intentional intelligent design and exchange that we find in human social groups. We can imagine our remote ancestors exchanging primitive tools for other tools or for food; we now do it with computers and cars. Thus from a lofty philosophical perspective economics is a branch of biology involving the basic twin generative processes: first make the product, then sell the product (ensure it is selected by purchasers). There is no discontinuity between genes and nature, on the one hand, and products and purchasers, on the other. There is a smooth transition from natural selection through artificial selection through economic selection. Darwin also included sexual selection in his list of types of selection; I am adding economic selection. Both of these are selection by conscious agents (peacocks and purchasers), but that doesn’t make them beyond the range of biology. Minds are a part of biology too. The dichotomy of culture and biology is artificial and misleading; economics belongs with both.[2]That is, economic culture is just another type of biological phenomenon. It is the same with business culture: that too is continuous with biology. Specifically, it involves the two generative components I have identified: creating the product and then marketing it, i.e. offering it up for selection by purchasers. The structure is the same. Markets are arenas of voluntary action, to be sure, but that doesn’t put them outside of biology or nature. In particular, economics is a generative science in the sense that biology is: it involves the generation of entities from raw materials and the generation of further entities by means of market forces. Production is like embryogenesis and buying and selling is like the selective survival of the fittest. Products go extinct if no one buys them, as animals go extinct if nature stops selecting them. We might even say that the Darwinian notion of natural competition is modeled on the notion of economic competition. Animals compete with each other in much the same way that products do. And of course the two intersect, as when animals are bought and sold (some breeds do better in the marketplace than others).

Just as Darwin’s theory is a theory of evolutionary change, so too economics is concerned with economic change—with how goods and services succeed each other in time. It is a dynamic science not a static science. The idea of a purely structural economics is a misguided one: economies are changing evolving structures just like animal species. The change can be slow judged by human standards, but the entire biological world is in constant flux; so too is the economic world. Supply and demand are forever changing. From a meta-economic point of view, then, economics shares the basic structure of biology (the same is true of linguistics and psychology—and even philosophy). In linguistics we are used to the idea that a grammar generates an infinite array of sentences—it is not merely a structural description; in economics too we should also think of economic mechanisms as generative—of products and of their adoption. A successful product is very like a thriving organism: there will be many instances of them and they will outperform the competition. This is the theoretical framework to adopt when considering the foundations of economics as a science. Economics is a generative biological science (so it is not like mathematics or logic). Capitalism, say, is a species of economic system that replaced feudalism, as mammals replaced dinosaurs. And it is still evolving into variant forms.

Let me suggest another analogy: verbal communication. A speaker is engaged on two generative tasks: (a) producing a grammatically well-formed sentence and (b) ensuring that she is understood by the hearer. The former does not entail the latter, which requires an additional generative effort—sufficient volume, getting the hearer’s attention, saying something interesting, etc. Similarly, the genes must produce an anatomically well-formed organism andone that will survive the pressures of natural selection—particularly, those arising from competition for resources and mates. Similarly again, a product must not only be functionally well designed but must also achieve market penetration in a competitive economic environment. The entrepreneur is like a speaker striving to be heard in a cacophonous world: she needs a sound product but alsothe means to be heard by potential consumers. It is necessary to generate supply anddemand (hence advertising etc.). Whether an animal will survive depends on the world it confronts as well as on its internal structure; but the same is true of a product. A speaker faces the same problem: first produce a good sentence but then ensure it is heard and understood. You have to create understanding as well as what is understood. These are different (though connected) tasks. So economics is not just a generative science; it is a doubly generative science.[3]



[1]I discuss this in “The Language of Evolution”, Philosophical Provocations(2017).

[2]I defend this view in “Biology and Culture: an Untenable Dualism”.

[3]This essay is a sequel to my earlier essay, “Memes, Behavioral Contagion, and the Zeitgeist”.


Drumming Tutorials

Let me give this more prominence: my demonstration of two new drumming techniques on Youtube. Just go to “Colin McGinn drumming tutorials” on Youtube. My drumming is a bit ropey but you will see the lessons I’m trying to impart.


Memes, Behavioral Contagion, and the Zeitgeist



Memes, Behavioral Contagion, and the Zeitgeist



I want to bring these three concepts together to create a meme that will be contagious and contribute to the zeitgeist.[1]First a quick introduction to our principal players: a meme is an idea or action that spreads analogously to the gene; behavioral contagion is the process whereby the actions of some members of a group are copied by other members of the group; the zeitgeist is the sum of all ideas and patterns of behavior prevalent at a given time in a culture. For example, a meme may be a melody or a catchphrase or a fashion; behavioral contagion occurs when yawning spreads from one person to another or mass hysteria grips a mob; the zeitgeist could be the belief system of medieval Europe or the mind-set of industrial capitalism. I want to say that memes are transmitted by behavioral contagion to form the zeitgeist: that is the basic structure of cultural (ideational) formation. I will generalize the concept of behavioral contagion to include not just behavior but also attitudes and ideas—psychological contagion.[2]Emotions can be propagated through a group as well as actions. The notion of contagion is taken from epidemiology: ideas can spread like a disease caught by social contact. Ideas can “go viral” in the sense that they leap from one mind to another, as bodies are invaded by a virus, leaving their mark as they disseminate. Thus the meme is the unit of transmission, psychological contagion is the method of transmission, and the zeitgeist is the totality of items transmitted. The three concepts all belong together.

We can take the gene as our basic model. The gene is the unit of inheritance, the focus of natural selection, and the driver of embryogenesis; it is fundamental to biology. As we know, it consists of DNA molecules—a certain type of physical structure. The gene is transmitted across generations, passing from one organism to another, somewhat like a germ (indeed biologists call this transmission the “germ-line”). Thus genes have the power to combine in one organism and spread to others. They are “contagious”. Inheritance is therefore the analogue of behavioral contagion—the way items replicate and multiply. Genetic transmission is a copying process just like the spread of fads and fashions, theories and obsessions. There is also the so-called gene pool—the totality of genes characterizing a species at a given time (along with the mega gene pool that includes all the genes on the planet at a given time[3]). This is the biological zeitgeist—the analogue of the “Spirit of the Times”. Thus we can map our three concepts onto concepts drawn from genetics: gene and meme, inheritance and psychological contagion, gene pool and culture pool. This provides a theoretical framework for thinking about cultural formation (as theorists have observed). What I am adding is the completion of the analogy to include means of transmission and to the sum-total of what is transmitted (psychological contagion and zeitgeist, respectively).

There is an abstract theoretical structure here: a replicating entity, a method of transmission from one host organism to another, and a repository of all the items capable of such transmission. Memes and genes are special cases of this abstract structure. Are there any other domains in which the structure applies? Written language appears to exemplify it. Words are the replicating units, which combine into larger units (phrases, sentences); writing is the means by which words are disseminated through the population; and libraries are the totalities that result from this dissemination. Words pass from one mind to another by a process of copying (e.g. “To be or not to be”) and books contain totalities of words. Thus we have word units, word transmission, and word pools. Reading and writing (and publishing) are the means by which words propagate and multiply and fill libraries. Indeed, inverting the analogy, we can describe the genome as a library of genetic verbiage, and embryogenesis as a process of “reading” the books of this library. Words produce copies of themselves by being transmitted between people; and a dictionary is a compendium of all the words of a language at a given time (a “lexeme pool”). As there is a spirit of the time, so there is a biosphere of the time, and a language of the time: replicating units that get transmitted through a population. And these three types of “pool” can have a characteristic shape at a given time—say, a religious shape or a dinosaur shape or an eighteenth-century British shape (see Thackeray and Austen). Certain words and styles of speech can be in vogue, or a certain type of organism dominant, or a particular system of thought communally received. These can mutate and be selected for or against, yielding to new formations (e.g. scientific thought, mammals, contemporary American English). Different domains have different categories of zeitgeist and different units of transmission, but the broad structure is common to all—replicating units, a means of spread, and a currently existing totality of favored items.

Is there anything else that exemplifies this structure? Yes: commodities, products, artifacts, bits of technology, machines. I mean to include a broad range of items here, ranging from motorcars to furniture, clothes to life-styles, food to computers. Things that can be bought and sold: these too can be analyzed in the tripartite way outlined. Take computers (or their parts): these are the units, the economic system is the way they are propagated, and the collection of them at a given time is the technological zeitgeist. The units are manufactured and sold, and they form the state of technology at a given time (the zeitgeist shifted when Apple came along). Behavioral contagion explains their widespread adoption. They are selected for or against in the marketplace. They reflect a given stage of technical and business evolution. Books fill libraries as genes fill genomes; commodities fill warehouses in the same way (and homes and offices). Genes, memes, words, and products: all are subject to the same overarching structure, the same logic. If products can’t be replicated or can’t be distributed, they won’t survive in the marketplace—just like genes or memes. Reproduction and transmission are essential, as is intrinsic quality (lousy TVs are as bad as lousy genes or lousy ideas). And the state of contemporary technology (in the broad sense) reflects the state of the world at that point in time—products come and go, as civilizations do, or animal species, or words. The zeitgeist is perishable and may be superseded by a superior zeitgeist (there are plenty of extinct zeitgeists). Thus we can subsume the business world under our general schema. The entrepreneur is swimming in a sea of replicators, contagion, and time-bound constraints—just like the biologist, the librarian, and the historian of ideas. Survival depends on navigating these waters, and it’s good to know what sea you are floating on and how the current flows. The successful entrepreneur needs to be aware of the conceptual structure that underlies and shapes his or her activities.[4]



[1]The literal translation is “time-spirit”; apparently Hegel preferred “Geist der Zeiten”, i.e. “Spirit of the Times”.

[2]Behavioral contagion belongs with other forms of social influence such as suggestibility, conformism, imitation, social facilitation, copycat behavior, and the like. What I want to emphasize is the more or less automatic absorption of social trends whereby something comes to permeate a population without any rational deliberation. It is sub-rational, below the radar, and sometimes insidious. Often it occurs by the release of inhibition triggered by an aberrant individual, as in copycat shootings or suicides. At the other extreme we have the general adoption of a particular accent. The human mind seems especially susceptible to this kind of subliminal influence. Memes need it to get off the ground and colonize a population—mere reproducibility is not enough. The channel must exist as well as the replicators that flow through it.

[3]The cosmic gene pool would be all the genes existing in the universe.

[4]I intend this to be the first of a series of essays about the theoretical model described, with special reference to the business world.


Against the Argument from Design


Against the Argument from Design


I have a parakeet, Emma, who developed a rather nasty infection about a year ago. Her feet became encrusted with some horrible-looking growth and her beak was discolored and deformed. I took her to the vet who diagnosed a parasite quite common in parakeets (but only in parakeets)—a tiny mite that lives in the feet and beak. A series of injections cured Emma of this ailment by exterminating the invading parasite. This made me think about the argument from design. That argument celebrates the beauty and ingenuity of design found in plants and animals, and argues that only an intelligent designer could explain this excellence of design. It’s like finding a watch in nature and inferring the existence of an intelligent and mighty watchmaker. But don’t parasites put a crimp in that argument? Who would design a creature susceptible to what Emma went through? I don’t mean ethically (though that is a question); I mean rationally. Isn’t it just bad design to make something so vulnerable to breakdown—why not create a parakeet that can’t be hijacked in this way? Suppose the watchmaker constructs a watch that is vulnerable to invasion by a common fungus that clogs up the works when it would be perfectly possible to build in a device that keeps the fungus out. Wouldn’t that be a better design? It is simply unintelligent to design a watch with such a flaw. True, the parakeet itself exhibits excellence of design, but making it the prey of a parasite is a design weakness. It is not that the designer can’t avoid such a flaw because it is an inevitable side effect of good parakeet design; it would be perfectly easy to keep the parasite at bay (after all, no other bird suffers from it). It looks like sloppy workmanship, sheer oversight, rank incompetence. It would be reasonable to infer that there wasno intelligent designer, given the lack of intelligence displayed by the alleged design product. Of course, we know that to be the case, given Darwinian theory—this is just a case of evolved inter-species competition. But what is striking is that the argument from design overlooks such failures of intelligent design, concentrating instead on traits that are good for the animal and beautiful in themselves. There is nothing good or beautiful about the deformed beak and feet suffered by Emma—if that were intentionally installed by a designer, we would think he or she an exceptionally incompetent designer (assuming good intentions). So really the argument from design proves that that there isno intelligent designer of nature—just as Darwin teaches us. From good design we might infer an intelligent designer (except for the alternative explanation provided by Darwin), but from bad design we can only infer the non-existence of an intelligent designer such as God is supposed to be. We might try to refurbish the argument to deliver only sometype of designer, albeit an inept and careless one; but clearly that would not get us to the conclusion envisaged by the classic argument from design. If God designed Emma in such a way as to be susceptible to the mite that plagued and deformed her, he is not the God we had supposed him to be. He is a watchmaker who should be banned from the watchmaking profession. Even if we didn’t have Darwin’s theory to fall back on, the argument from design is therefore flawed on its own terms; if anything it proves that nature is unintelligently designed.[1]


Colin M

[1]Of course, that is just what it is: the process of natural selection is not an intelligence-driven process. It may mimic intelligent design in some respects, but if you look deeper there are signs of the lack of intelligence everywhere (e.g. human anatomy).





I’m getting the distinct impression that we’re doomed. I can feel it in my bones. First, philosophy in America is doomed; indeed, it is now more or less defunct (relative to earlier times). Once the older generation dies off in five to ten years we will be left with a desert of mediocrity and infighting, which will probably invite institutional elimination (no one will want to study it to start with). Second, democracy is doomed: it was never well thought out to begin with and has obvious structural weaknesses. Already it is fraying and fracturing (Trump, Brexit, China), and young people are no longer the hope for redemption (see Euphoriaand the general state of the Internet). Third, the human race is doomed by its stupidity and selfishness (climate change, nuclear war): there is no way the people of the world will make the sacrifices they need to in order to avert catastrophe. It’s only a matter of time till global warming leads to all-out war, not to mention the eruption of simmering conflicts. Fourth, the planet is doomed—at least many animal species are. The rate of species extinction is already alarming and will only increase; this will lead to ecological catastrophe on a grand scale. Some species will probably survive, but planet earth will be a much-reduced place. This to me will be the greatest tragedy. I see in human nature as it is manifesting itself today an unprecedented level of hysteria and foolishness, coupled with moral blindness and sheer greed. Once evil gets a grip it is hard to stop it, till the final collapse puts an end to everything. It takes a lot to create something, but destruction is easy.



Truth-Value Gaps and Meaning


Truth-Value Gaps and Meaning



Sentences exhibiting truth-value gaps would appear to pose a significant problem for truth-conditional semantics. Such sentences evidently have meaning, yet they are neither true nor false. In this respect they resemble non-indicative sentences such as imperatives. But imperatives can be handled by adopting a parallel concept like obedience conditions and proceeding in the usual way.[1]How do we deal with sentences like “The king of France is bald” or “Colorless green ideas sleep furiously” or “All my parakeets are asleep” (said when I have no parakeets). These sentences are as meaningful as any, yet they lack truth-value.[2]And there are infinitely many of them, as many as there are sentences with truth-value. Should we conclude that Tarski-style semantics for them is impossible? They don’t even have falsity conditions, so how could they submit to a recursive definition of the kind Tarski showed how to provide? We understand such sentences—our linguistic mastery encompasses them—and we also appreciate thatthey lack truth-value, so how can truth-based semantics apply to them?

It is an interesting fact that there is no simple predicate capturing the condition of being neither true nor false, so theorists adopt the makeshift “gappy”, or we could stipulate a use for “vacuous” applied to whole sentences (as in “vacuous names”). For convenience I will abbreviate “neither true nor false” to “NTF”, so that I can say that a sentence sis NTF if and only if p, where pis some sentence in the meta-language yet to be specified. The question is what that sentence will be. For truth we simply repeat the sentence of the object language (or a translation of it), for falsehood we prefix the sentence on the right with negation—what do we do for “NTF”? What we need is a necessary and sufficient condition for the semantic predicate “NTF” to apply. It seems fairly obvious what this should be: sis NTF if and only if it is not the case that either por not-p, where pis (or translates) s. For example, “The king of France is bald” is NTF if and only if it is not the case that the king of France is either bald or that he is not bald. That is, the law of excluded middle doesn’t apply to the sentence in question. If there is no king of France, he can’t be either bald or not bald, so a sentence affirming that he is bald is neither true nor false.[3]Notice that the condition on the right hand side is not meta-linguistic, so it resembles the usual disquotational conditionals made famous by Tarski. We could say that “snow is white” is made true by the fact that snow is white, “snow is black” is made false by the fact that snow is not black, and “The king of France is bald” is made neither true norfalse by the fact that he is neither bald nor not bald. Similarly, it is not a fact that colorless green ideas sleep furiously or that they don’t, so the sentence stating this is neither true not false. When a speaker understands such a sentence she knows that the facts don’t give it a determinate truth-value, and her understanding is displayed by the biconditional enunciated. We have the usual mention-use pattern of classical truth theories, but the right hand side doesn’t just repeat the left—it provides a more complex condition. The same is true for falsity, because there we have to add negation. Not all semantic biconditionals are “homophonic”.

Employing this basic format, we can provide recursive clauses in the usual manner.  Thus “pand q” is NTF if and only if both pand qare NTF; “por q” is NTF if and only if either por qis NTF[4]; “not-p” is NTF if and only if pis NTF. To deal with quantified sentences we introduce the notion of a “true of” (satisfaction) gap: the predicate is neither true nor false of a putative object (such as a French monarch). The reference of the description is neither bald nor not bald, since there is no such reference. Compare “Vulcan revolves”: the putative planet Vulcan neither revolves nor fails to revolve, so it doesn’t satisfy “revolve” or dissatisfy it. Thus we can apply the standard Tarskian apparatus to the concept of a truth-value gap, mutatis mutandis. We can therefore provide a recursive disquotational definition of the predicate “NTF”. We could call the form of this definition “Convention NTF” and require that for any sentence of the object language such a meta-language sentence be derivable. Thus we have Convention T for truth, Convention F for falsity, and Convention NTF for neither truth nor falsity: the first simply repeats the sentence, the second introduces negation, while the third deploys negation plus disjunction. For “snow is white” to be true is for snow to be white, for “snow is white” to be false is for snow not to be white, and for “snow is white” to be neither true nor false is for snow neither to be white nor not white. Thus we bring sentences exhibiting truth-value gaps within the fold of Tarski-style theories—not by subsuming them under the concept of truth but by extending the apparatus beyond that concept. We might call this generalized truth-theoretic semantics.

It is a question whether every sentence has an NTF condition, not just those that are actually neither true nor false. Do we, in understanding “snow is white”, grasp under what conditions it would be neither true nor false, as we grasp its truth conditions and its falsity conditions? We grasp this for sentences that are NTF because we recognize their “gappy” status, but do we also grasp it when we know that there is nothing gappy going on? I rather think we do: for we grasp what it wouldbe for them to be NTF. I know that “snow is white” would have a truth-value gap ifsnow were neither white nor not white—though I also know that it is actually one way or the other. If you ask me under what conditions the sentence would be NTF, I can tell you—if there’s no fact of the matter about the color of snow (as there is no fact of the matter about the color of Hamlet’s hair). So NTF conditions are pervasive in the understanding of language: they are part of what every speaker (tacitly) knows. Every sentence has conditions under which it wouldbe NTF, say by the subject-term lacking a reference (and this is always an epistemic possibility[5]), and this is something speakers grasp at some level. So a semantics for the predicate “neither true nor false” is applicable everywhere. We all grasp something of the form: “snow is white” wouldbe neither true nor false if and only if snow was neither white nor not white (possibly by not existing). NTF conditions are as much grasped as truth conditions and falsity conditions.



[1]I wrote about this in my 1977 paper “Semantics for Non-Indicative Sentences”, Philosophical Studies.

[2]I am going to assume the existence of meaningful sentences with truth-value gaps without arguing for it. My question is what happens to semantics ifwe accept such sentences. I will also not discuss all the possible examples that have been offered: vague sentences, future contingents, empty names and demonstratives, ethical sentences, etc. What I propose will carry over to these cases.

[3]It is worth noting that empty descriptions can also occur in imperative sentences such as “Kill the king of France!”, so we have obedience-value gaps as well as truth-value gaps. Then too we have “Bring me some colorless green ideas!”

[4]Actually this clause is too simple given the case in which pis true and qis NTF, since this will make the disjunction come out true. We could append “unless pis true” to cover this case, but for simplicity I will stick with the condition as stated in the text.

[5]In the extreme case in which we are brains in vats and our noun phrases are empty of reference, truth-value gaps will be ubiquitous, and hence the correct semantics for our language will be largely NTF semantics.


Belief, Desire, and Action



Beliefs, Desires, and Actions


Consider actions in which the agent uses a piece of technology (in a broad sense) to achieve a desired goal: using a car to get to a certain place, using a cell phone to communicate, taking an umbrella out in the rain, using a hammer to knock in a nail. It is natural to analyze the psychological background of such actions as involving (a) a certain desire and (b) a belief about the means to achieving that desire. For instance, the agent wants to get to a certain place and believes that driving a car is the best means to achieve this goal. There is a combination of belief and desire at work, which leads to the performance of the action. Theorists of action have seen in this kind of case a general analysis of action: any action is caused and explained by the presence of an antecedent pair of a desire and a belief, where the belief specifies the means to be adopted to satisfy the desire. The desire alone will not prompt or predict the specific action performed—an accompanying belief is also required; nor will the belief alone suffice to elicit the action—an accompanying desire is required. A desire to stay dry will not prompt you to take an umbrella unless you believe that umbrellas keep you dry, and the belief that umbrellas keep you dry will not prompt you to take one unless you desire to stay dry (you might feel like getting soaked today). Thus there arises a certain doctrine about the psychological basis of action: any action requires the presence of a desire anda belief—both are necessary conditions (and together possibly sufficient) for an action to occur. This is supposed to be an interesting and unique fact about action and its explanation, suggesting a certain kind of “holism” about psychological explanation. Let’s call it the “Combination Thesis” (or “CT” for short): the thesis that all actions are consequences of a belief-desire pair acting in concert. Thus we arrive at something called “belief-desire psychology”, taken to be a general format for psychological explanation: any explanation of action requires the specification of a desire and an instrumental belief concerning how best to satisfy that desire. Action is the result of something cognitive and something appetitive operating together.

I propose to question this widely held picture. I think it arises from overgeneralizing one sort of example of action—the kind that involves means-end reasoning. In particular, I think that some actions occur without any instrumental belief and some occur without any desire (in a natural sense of “desire”). That is, there are one-factoractions—just a belief or a desire operating on its own. The Combination Thesis is false, except in a limited range of cases; it is not fundamental to action as such. Let us consider a very simple kind of action: flexing one’s index finger. Suppose an agent has a desire to flex his index finger and does so: what means-end belief accompanies this action? On the face of it, none: he didn’t believe that a certain device was a good means to bring about the desired result. The agent didn’t think that contracting certain muscles in his forearm would be a good means to flex his finger—he simply did it. And even if such a thought had entered his head (maybe he specializes in hand physiology), there would be the question of whether thataction needed a belief about means for it to be performed (say, initiating efferent nerve impulses from the brain). No, the action simply resulted from a desire, with no means-end belief involved (no technology is being exploited). It is the same for swallowing, breathing, walking, swimming, etc. You don’t believe that swallowing is a good way to get food into your stomach when you eat, or that putting one foot in front of the other is a good way to walk—any more than animals do. You just do it. It is absurdly intellectualist to suppose otherwise. It is not as if you have an array of options available for getting food inside you, such as inserting it through your navel, and you choose one of them as the best means in the circumstances. Chewing and swallowing are just nature’s way of getting fed, not a cunning plan you have devised for achieving satiation.[1]You have a desire for food, so you do what comes naturally, as you do when inhaling oxygen into your lungs. In general, movements of the body (often called “basic actions”) are not preceded by means-end reasoning: a person never moves her body by reasoning about the best means of doing so. That is, basic actions are not subject to CT. Raising my arm is not something I need an instrumental belief to perform. If I want to raise it, I raise it, without consulting possible means. Thus the explanation of a basic action has the form, “Xdid Abecause he desired to do A”. It is the same for adult humans, infant humans, and most animals: basic movement is caused by a desire not by a desire-belief combination. There is simply no need for belief: the mind and body are just wired (innately or by learning) to translate desire into action. The right thing to say is that where there is means-end reasoning there is a belief corresponding to the means that combines with a desire, but in more basic cases there is no such belief, since there are no such means. A specific feature one kind of action has been overgeneralized to apply to all action. Indeed, whenever CT does hold there is always a basic action for which it does not hold, i.e. a movement of the body. This is even clearer for purely mental action such as calculating in the head: if I add two numbers in my head, I don’t have an instrumental belief about how best to get the result I want. I want the answer and I’m wired to get it (I know arithmetic); I don’t need any superintending belief about the best means of getting it. Another way to put the point: in tactical practical reasoning agents have instrumental beliefs, but most action is not of a tactical kind. What psychologists call sensory-motor activity is generally not tactical or instrumental or belief-driven; it is automatic, programmed, not thought out.

But is desire always necessary for action? It depends what you mean by “desire”, which tends to be a philosopher’s term of art (sometimes glossed as “pro-attitude”). It seems right to say that the agent needs to view the action favorably (certainly not unfavorably), but there are ways of doing that that are not really cases of desire. Suppose you believe that you have a certain desire but you don’t really have it (you have been brainwashed into the belief): won’t you still be inclined to do the thing in question? Then your action will be motivated by a belief abouta desire, but not by that desire—you apply to medical school, say, because you have been brought up to believe that medicine is your calling (in fact, it’s opera). This would be a case in which you act on a belief without the corresponding desire, though you can be said to view the action favorably. And isn’t it generally true that desires influence actions only if they are recognizedin some way? How could desires of which you are completely ignorant figure as causes of action (even unconscious desires need to be recognized by the unconscious executor)? Their existence has to be registered or acknowledged. So something like belief has to be added to them to produce action; and then we have the question how much the belief contributes to motivational force. This gets pretty messy, psychologically. The neat picture of the pristine desire and its helpful belief companion starts to seem too simplistic. Motivation has (or can have) a more complex and variable structure.  You can do something simply because you have a sudden urge to do it, and you can also do something because you believe you desire to (though you don’t)—in either case you lack one of the components postulated by CT. So there are now three types of case to consider: (i) belief and desire in combination, (ii) desire alone, and (iii) belief alone. Some theorists have argued that moral motivation consists of nothing but a moral belief; we need not take a stand on that issue to accept that beliefs aboutdesire can play a motivational role. Being under the impression that you have a certain desire can act as a prompt to action, whether you have that desire or not. Maybe the only general thing we can say is that the action has to look desirable to you—there is something to be said in favor of doing it. This can take the form either of desire plus belief, or simply desire, or believed desire (or maybe just belief that the action would be morally good). Animal action will largely consist of the second category; agents with advanced practical reasoning will do a good deal of the first kind; the third kind will be restricted to those individuals deluded or confused about what it is they really want. There is no psychological structure common to all cases. The psychology of action is not monolithic.

Suppose someone suggests that action is what is caused by need, so that to explain an action we must specify what need it serves. This theorist is perhaps impressed by the actions of certain animal species of a somewhat primitive type. The natural response would be that this is too simple, too parochial: not every action is prompted by a biological need, and actions sometimes require practical reasoning involving instrumental belief. The need theory applies to some cases but certainly not to all. Well, belief-desire psychology, as currently understood, is rather like that: it fits some cases well enough, but it is too uniform and simple. There are a variety of different kinds of motivational state, ranging across a wide spectrum. In some ways the theory is too complex (because of basic actions) while in others it is not complex enough (because of cases like false beliefs about one’s desires). Thus reasons for action are of different types, not always resolving into the two-factor model of CT. Pluralism about reasons is the indicated position.[2]


Colin McGinn

[1]Sub-intentional actions, such as rolling one’s tongue around one’s mouth or tapping one’s foot nervously, seem particularly unsuitable to the belief-desire treatment: what instrumental belief do I have when my tongue is rolling around pointlessly? Just as the heart has no instrumental belief when performing the act of pumping blood, so many of our more automatic actions are free of cognitive supervision.

[2]All reasons may be causes, but the causes can vary as to type. Desires themselves can come in many types, from the moral to the animalistic. Nor is there less variety in the concept of belief. It is variety all the way down.