Uncategorized - Colin McGinn

The Evolution of Color

June 4, 2021/0 Comments/in Uncategorized/by Colin McGinn

The Evolution of Color

According to projectivist views about color, color properties do not precede color vision. It is in virtue of color experiences in perceivers that things come to be colored. Color is mind-dependent. I will assume this view here. My concern is with the consequences of this view for the theory of evolution.

Sensations evolve: they result from genetic mutations acted upon by natural selection. They are adaptive traits, just like bodily organs; they are there for a reason. Thus the feeling of pain has biological utility (as a warning sign and motivator), and even the phenomenological details of the sensation will have been subject to fine-tuned natural selection. The feeling of orgasm must be similar: it is the way it is for strictly biological reasons–as the best method the genes have for securing their survival. These traits are internal—sensations occur “inside” animals. They are part of what we might call the restricted phenotype: they belong with eyes and stomachs and other organs of the body. Their design follows the general rules of trait selection: they are solutions to evolutionary problems, more or less efficient, constrained by the past, and handed down through the generations.

Tastes and smells are similar, only now it is external objects that have tastes and smells—whereas it is organisms that have sensations. Things taste and smell as they do for strictly biological reasons. As organisms evolve, tastes and smells come into being, though they are tastes and smells of external things. They are projected not inherent, relational not intrinsic. And it is the same for colors: objects are colored but they are so only in virtue of the existence of evolved organisms that see them that way. There were no tastes, smells, and colors before sentient organisms evolved. Thus we can say that colors evolve—like sensations of color. Red objects, say, came into existence (qua red) by means of genetic mutation and natural selection. If red were not an adaptive color for organisms to see, then it would not have evolved: red is a biologically useful color to project. In general, the colors organisms see must have been specifically selected for their adaptive value—presumably because of their ability to provide sharp contrasts (among other things). In other words, natural selection operates on colors—even though it is external objects that are colored (in virtue of color vision). If the genes for color vision were to mutate so as to produce a completely different set of perceived colors, and these new colors were more adaptive than the ones we now see, then we would find a selective pressure in favor of these mutated genes. The world contains the colors it does because of the selective pressures operating on organisms.

That may sound odd, because colors, unlike sensations, are not properties of organisms—they are properties of external objects (though projected there). They are not part of the organism’s restricted phenotype, i.e. existing within its individual boundaries. But here we must remember the notion of the extended phenotype: it is not just the individual body type that is selected, but also what that body produces environmentally. Thus the beaver’s dam and the bird’s nest are part of these animals’ extended phenotype: natural selection works on the combination of body and external product, so that good dams and nests are favored, along with good limbs and brains. Body plans and behavioral capacities evolve, but so do the adaptive products of those things—she who builds the better dam or nest is most likely to pass on her genes. The unit of natural selection is the extended phenotype not merely the restricted phenotype. And now the point I want to make is that colors are part of an organism’s extended phenotype. They are products of minds and brains, like dams and nests, but they exist outside the boundaries of the organism—hence they belong to the extended phenotype. They evolve by the same rules as bodies, but they are not parts of bodies. As dams and nests evolve, so colors evolve (and sounds, tastes, and smells). Colors are created by genes, ultimately, and the better the color the more chance it has of surviving. The colors we see now in the world have stood the test of evolutionary time. The colors we project are the colors that have passed selective muster. Red, for example, has proved itself a highly adaptive color, along with the usual color spectrum that we see. Wishy-washy or indistinct colors might not do as well in the fight to survive—just as feeble or painful orgasms would not be apt to survive, in contrast to more pleasurable ones. In the case of colors, we might say that they belong to the projected phenotype—which is a subclass of the extended phenotype. The organism builds its physical environment (sometimes), but it also constructs its perceptual environment. It constructs a phenomenal world. This world consists of colored objects (among other things); so colored objects evolve (though not the matter they are made from). Evolution thus operates selectively on phenomenal worlds, as it operates selectively on limbs and brains. Whole species of phenomenal world come into existence by mutation and natural selection.

Some properties of objects do not evolve—those that precede and are independent of organisms—but some do. Projected properties do, because they reflect the perceptual receptivity of organisms. When I say that colored objects evolve I obviously don’t mean that the objects themselves have evolved by natural selection; I mean that their having the colors they have is a result of natural selection–there are no colored objects on the planet without natural selection. It is because colors are both properties of objects and projected by the mind that they belong to the extended phenotype of the organism. If they were psychological properties of organisms, they would be part of the restricted phenotype; and if they were inherent properties of external things, not projected properties, they would simply be part of the non-evolving environment. The point is not that experiences of color evolve—that follows simply from the fact that sensations evolve. It is rather that the colors that are the objects of such experience evolve—as dams and nests evolve. Dams and nests are adaptive traits for beavers and birds, and colors are adaptive traits for visual organisms—though these traits all belong in the extended phenotype. As adaptive traits, they are subject to evolution by natural selection. The colors that exist in our world are those that have survived the rigors of natural selection.

It may help in understanding the point if I make the ontology of colors clear. The projectivist view of color is naturally associated with a dispositional theory of color ascriptions: objects have the colors they are disposed to produce experiences of—an object is red, say, in virtue of being disposed to produce experiences of red. This need not imply that colors are identical to such dispositions: we can hold that colors supervene on these types of dispositions, without being identical to them. Then we can say that colors are simple qualities of objects, not in themselves mental, but that they are instantiated in objects in virtue of dispositions to produce color experiences. Color experiences clearly evolve, and objects only have dispositions to produce such experiences in virtue of the existence of evolved organisms; but it is a further claim that colors themselves evolve—conceived as simply qualities of external things. We thus have the nontrivial thesis that objects come to have simple color properties in virtue of evolution by natural selection. A mutation caused some object to look red, and hence (by projection) to be red; then natural selection favored that way of seeing, and hence what is seen. Colors came into the world by the same mechanism as hearts and kidneys. To put it paradoxically: it is adaptive for us to be surrounded by colored objects.

Does this view of color generalize? It certainly generalizes to other secondary qualities, but it may also generalize to qualities traditionally regarded as primary qualities, such as shape and motion. For it may well be that such qualities do not rightly belong in the austerely objective world described by physics; rather, they reflect our evolved sensibility—how we have been programmed to experience the world. If so, shape and motion—the perceptible qualities we experience—are also evolved (and evolving) entities. Objects have shape and motion, as we perceive them (if not in the austere world of physics), but they do so only as a result of our evolved sensibility; so they too are subject to evolution by natural selection. The whole world of colored objects with shapes and in motion is caught up in the evolutionary process: it originated in that way and its survival depends on the usual evolutionary pressures. In other words, the world we experience is an evolutionary product—like limbs and brains, dams and nests. The empirical world is really part of our extended phenotype. [1] So the extended phenotype extends quite far into reality (though not all the way). When did this naturally evolved empirical world come to exist? It probably had its early origins in the projective mind of a sentient fish a billion or so years ago. Then it was that the world began to be clothed in color (and maybe shape and motion, as we conceive them in common sense). It has been evolving ever since, becoming ever more complex and subtle. It will cease to exist when there are no more sentient organisms projecting properties onto the world. Colors will eventually become extinct, joining the dinosaurs.

[1] But not the whole of reality since there is an objective world out there that owes nothing to our evolved modes of experience. It is the world as it appears to us that belongs to the projected extended phenotype—but this world contains real (though projected) properties of things.

The Cruel Gene

June 4, 2021/0 Comments/in Uncategorized/by Colin McGinn

The Cruel Gene

I can forgive the genes their selfishness; it is their cruelty I can’t forgive. [1] I understand their need to build survival machines to preserve themselves until they can replicate: they need the secure fortress of an animal body. But why did they have to build suffering survival machines? Hunger, thirst, pain, and fear—why did they have to make animal bodies feel these things? Granted the survival machines benefit from having a mind, but it was cruel of the genes to produce so much suffering in those minds. Couldn’t they have found another way? Are they sadists?

The answer is that suffering is an excellent adaptation. Genes build animals that suffer because suffering keeps the animal on its toes. If the body is the genes’ bodyguard, it pays to make the bodyguard exceptionally careful. Since pain signals danger, and hunger and thirst signal deprivation, and fear motivates, the genes will build bodyguards that are rich in these traits. To build a bodyguard that suffered less would be to risk losing out to genes that build one that suffered more. This is why we find suffering so widely in the animal kingdom—because it is so useful from the genes’ point of view. It probably evolved separately many times, like the eye or the tail. Pain also has many varieties, also like the eye and tail. There doesn’t seem to be any complex animal that lives without suffering, so the trait is clearly not dispensable. Surviving and suffering therefore go hand in hand.

Most adaptations have a downside: a thick warm coat is a heavy coat, brains use up a lot of energy, and fur must be groomed. In fact, all adaptations have some downside, because all need maintenance, which calls upon resources. But pain and suffering have very little downside from the point of view of the genes. They don’t slow the animal down or make it lethargic or confused; on the contrary, they keep it alert and primed. The avoidance of pain is a powerful stimulus; hunger is a terrible state to be in. Animal behavior is organized around these aversive psychological states—and the genes know it. They are cruel to be kind—to themselves: suffering helps protect the survival machine from injury and death, so the animal lives longer with it than without it, with its cargo of genes. The reason the genes favor suffering is not from altruistic concern for the life of the animal, but merely because a longer life helps them replicate. The genes aim to reproduce themselves, and this requires a fortress that can withstand adversity; suffering is a means they have devised for keeping their fortress alive and functioning until reproduction can occur. Since there is so little downside to pain, from their perspective, they can afford to be lavish in its production. Thus the animal suffers acutely so that they may survive. They know nothing of pain themselves (or anything else), but natural selection has seen to it that pain is part of animal life. Nature has selected animals according to the adaptive power of their suffering. Genes for suffering therefore do well in the gene pool.

Suffering has no meaning beyond this ruthless gene cruelty. It exists only because natural selection hit upon it as an adaptive trait. A mutation that produced a talent for pain, probably slight pain initially, turned out to have selective advantage, and then the adaptation developed over the generations, until spectacular amounts of pain became quite routine. As giraffes evolved long necks, and cheetahs evolved fast legs, so animals evolved high-intensity pain. As an adaptation, pain is very impressive, a clever and efficient way for genes to keep themselves in the gene pool; it is just that pain is very bad for the animal. Pain is an intrinsically bad thing for the sufferer—but it is very beneficial to the genes. But they don’t care how bad it is for the sufferer—they don’t give it a second thought. Pain is just one adaptation among many, so far as they are concerned. Maybe if there was another way to obtain the beneficial effects of suffering—another way to keep the survival machines on their toes—the genes would have favored that: but as things are suffering is the optimal solution to a survival problem. The genes are unlikely to spare the animals that contain them by devising another method more compassionate but less efficient. Suffering just works too well, biologically. It wasn’t used for the first couple of billion years of life on earth, when only bacteria populated the planet; but once complex organisms evolved pain soon followed. It probably came about as a result of an arms race, as one animal competed with another. Today plants survive and reproduce without suffering: it is not an element in their suite of adaptations. They are the lucky ones, the ones spared by the ruthlessly selfish genes. Mammals probably suffer the most, and maybe humans most of all, at least potentially. We suffer acutely because the genes decided they needed an especially finely tuned and sensitive survival machine to get themselves into future generations. The possibility of excruciating torture was the price they left us to pay. Theydon’t suffer as their human vehicle endures agonies; yet the reason the agonies exist is to benefit the genes. The genes are the architects of a system of suffering from which they are exempt.

Animals are probably tuned better for suffering than for pleasure and happiness. It is true that the contented sensation of a full belly is a good motivator for an animal to eat, but then the animal has already eaten. Far more exigent is the demand that an empty belly prick the animal into action. The pleasure of grooming might motivate animals to groom, thus avoiding parasites and the like. Far more exigent is the need to avoid injuries from bites and battering. The system must be geared to avoidance, more so than to approach. Thus animals are better at suffering than at enjoyment—their suffering is sharper and more pointed. Some animals may be capable of suffering but not enjoyment, because their pattern of life makes that combination optimal. But no animal feels enjoyment in the absence of a capacity to suffer, not here on earth. Suffering is essential to life at a complex level, but enjoyment is optional.

This is why I can’t forgive the genes: with callous indifference they have exploited the ability of animals to suffer, just so that they can march mindlessly on. They have no purpose, no feelings, just a brute power to replicate their molecular kind; and they do so by constructing bodies that are exquisite instruments of pain and suffering. If they were gods, they would be moral monsters. As it is, their cruelty is completely mindless: they have created a world that is terrible to behold, yet they know nothing of it. It just so happens that animal suffering follows from their prime directive—to reproduce themselves. Animal suffering is how the genes lever themselves into the future. It is one tactic, among others, for successful replication. Its moral status is of no concern to them. The genes are supremely cruel, but quite unknowingly so—like blind little devils.

Colin McGinn

[1] I indulge in rampant personification in this paper, knowing that some may bristle. I assure readers that it is possible to eliminate such talk without change of truth-value. Actually it is a helpfully vivid way to convey the sober truth.

Particles and Identity

June 4, 2021/0 Comments/in Uncategorized/by Colin McGinn

Particles and Identity

In the case of statues and similar objects we can separate the identity of the thing from its substance. Thus the statue is not identical to the piece of bronze that composes it, because the piece but not the statue survives being melted down. The piece is the aggregate of its constituent particles, but the statue is a particular form of that aggregate. For composite objects in general, the object is not identical to the mass of particles that composes it: the constitution relation does not coincide with the identity relation.

But what should we say about the particles themselves? Suppose that electrons are physically basic: can their identity come apart from their constitution? Could we melt down an electron so as to destroy the electron but leave its substance intact? That could not consist in rearranging its constituents, because it has none. We cannot destroy the electron and leave the aggregate of its parts intact, since it is not composed of an aggregate. So it is not clear what it would be for its substance to survive the destruction of the electron itself. We can’t remove the form of the electron and leave the elements that compose that form. You might try saying that we could destroy the electron but leave its single constituent intact. But it is that single constituent, so when the electron goes it goes too. Nor can we suppose that the electron is composed of a substance that does not consist of electrons: for what could that substance be? If it were composed of some other type of particle, we could just repeat the argument for that particle.

For simple objects, then, we cannot produce a statue-type example. The existence of the object and the existence of its substance cannot be pulled apart. At the basic level, constitution is identity. Not everything is composed of something to which it is not identical. So the distinction between identity and constitution is not a deep fact about the universe. It arises only at the level of composite objects.

Appearance Without Reality

June 4, 2021/0 Comments/in Uncategorized/by Colin McGinn

Appearance Without Reality

Is it possible for everything to be an appearance? Might there be nothing in the world but appearances? Granted, there may be many appearances for which there is no corresponding reality (of the kind that we normally suppose), but could this be universally true? Is the pure-appearance world a possible world? I think not, for two reasons. First, appearances must be appearances to someone: there cannot be appearances that float free of a subject for whom they are appearances. Nor can a subject be an appearance of a subject—for who is that appearance an appearance to? Second, appearances must have causes outside themselves: they cannot be self-causing or entirely uncaused. Not all realities need to have a cause (say, the first cause), but appearances cannot come to exist causelessly. This is because they must be appearances of something, and that something cannot itself be an appearance. The logical form of appearance statements is: “A is an appearance of x to y”. That is the structure of appearance. So every appearance has a non-appearance cause. An appearance may be caused by an external object in the standard way, or it may be caused by the state of a brain existing in a vat, or it may be caused by God’s magic touch: but it has to be caused by something. The epistemological problem of appearance is that we don’t know for certain what the nature of the cause is—hence skepticism. We know that there has to be some cause, but we don’t know what cause. We know that our visual experiences, for example, are caused by something, and we may even have an exhaustive list of all the possible causes, but we cannot definitively select a particular item from the list. The appearances underdetermine their specific cause, but they necessarily have a cause—and that cause must be sufficient to bring about the appearances with their specific character. But appearances are not of such a nature that their cause can be read off them. That’s the trouble with appearances qua appearances. Still, we know that they must have some sort of non-appearance cause; so the world cannot consist solely of appearances. There must be a reality that appears and a reality that appearances appear to—there cannot be appearances alone. It cannot be appearances all the way down.

Truth and Existence

June 4, 2021/0 Comments/in Uncategorized/by Colin McGinn

Truth and Existence

The concepts of truth and existence form a natural pair. They are both highly general abstract concepts. They have both been suspected of being pseudo-properties, expressed by logically misleading predicates. They have both been declared redundant, adding nothing to their bearers: calling a proposition true amounts to no more than affirming the proposition, and ascribing existence to a denoted object does nothing more than bring out what is presupposed in denoting that object. Also, truth pairs with falsehood in the way existence pairs with non-existence: truth and existence are positive attributes, while falsehood and non-existence are types of lack. Truth and existence are deemed good, while falsehood and non-existence are deemed bad: we aim to assert what is true, as we aim to refer to what exists. If we fail in these aims, we do something amiss. Finally, it has often been supposed that truth and existence are fundamental and indefinable concepts, with the associated properties ontologically primitive (and vaguely “queer”). Neither property can be perceived via the senses, and neither plays a causal role in how the world works. They both seem non-empirical, non-natural, and oddly diaphanous.

This raises the question of whether truth and existence are related in any way: do they perhaps enter into each other’s essential nature? If there is any interesting connection, it will not be simple—not a matter of defining one in terms of the other by substitution. Thus it is hopeless to suggest that ”p is true” means “p exists”, since a proposition can exist without being true (though the former follows from the latter). And it is equally hopeless to equate “a exists” with “a is true”, since objects cannot be true (or false). Clearly truth and existence are not the same property. But the connection might be less direct—one concept might be linked to the other in combination with other concepts. Thus consider: “A proposition is true if and only if it designates an existing state of affairs”. That sounds very much on the right lines (Tarski mentions it as a possible definition of truth). Note that we need to include “existing” here because a proposition might designate a possible state of affairs that does not exist (is not actual): the possible state of affairs of snow being yellow does not exist. The world is the totality of existing states of affairs. Given that we are happy with states of affairs, and with applying the concept of existence to them, this seems like a perfectly worthy definition of truth; and it contains the concept of existence essentially. Thus truth is conceptually linked to existence.

What about the other way round—is existence linked to truth? The following sounds right: if a exists, then we can make true statements about a. If a does not exist, then we cannot make true statements about a—we can make only false statements or statements that are neither true nor false. Existence is a necessary condition for true predication: we cannot speak truly of something that does not exist. Someone might object that this principle is false for fictional objects, since we can say truly that Sherlock Holmes is a detective. Maybe or maybe not, but we can easily strengthen the principle to say that existence is a necessary condition of literal or factual truth. Thus the concept of existence entails a consequence concerning truth—existence is what makes truth possible. In a world with no existence there is no truth. If we are feeling ambitious, we might even try to define existence this way: an object exists if and only if there are true statements about it. This would be the analogue of defining truth in terms of existing states of affairs. But we do not need to go that far in order to recognize a non-trivial conceptual link—a kind of mutual conceptual dependence. Grasp of the concept of truth involves grasp of the concept of existence and vice versa: one concept feeds into the other.

Granted these links, the similarities between truth and existence fall naturally into place: they are concepts that presuppose each other. Truth is all about the existence of states of affairs, and existence is all about the stating of truths. Truth is a certain kind of existence, and existence is the basis of truth. We have the word “true” so that we can describe existing of states of affairs, and we have the word “exists” so that we can describe what makes truth possible. We could get along without these short words, using only the longwinded formulations, saying things like, “Your statement designates an existing state of affairs” and “a meets the condition for allowing true statements about a”. What is notable about these definitions is that each concept incorporates the other concept essentially. Thus truth and existence are natural conceptual partners: they point towards each other.

Colin McGinn

A Refutation of Positivism

June 4, 2021/0 Comments/in Uncategorized/by Colin McGinn

A Refutation of Positivism

The positivists maintain that a sentence is meaningful if and only if it is verifiable. Thus a sentence can be said to be both meaningless and unverifiable. Here is a possible counterexample to that claim: “It’s raining”. This sentence is not meaningless, but it is not verifiable–and similarly for all other indexical sentences. Considered out of context, just in virtue of their lexical meaning (what Kaplan calls character), such sentences are not verifiable—they are unverifiable. It will be replied that we need to consider such sentences in a context in order for them to be verifiable—we need to consider the proposition they express in a particular context of use (what Kaplan calls content). That is undoubtedly correct, but now we are talking about propositions (or statements or sentences “under an interpretation”), not sentences per se. Thus we might reformulate the positivist’s principle to read: A sentence is meaningful if it expresses a proposition that can be verified, and it is meaningless if it expresses a proposition that can’t be verified. (The same point goes for falsifiability as a criterion of meaningfulness.) This implies that a sentence can be meaningless and yet express an unverifiable proposition. But how can a sentence be meaningless if it expresses a proposition? Either it expresses no proposition, in which case it cannot be either verifiable or unverifiable; or it does express a proposition, in which case it is meaningful. Meaningfulness (or the lack of it) is a property of a sentence; verifiability (or the lack of it) is a property of a proposition. The positivist’s principle conflates this distinction, which is what enables it to sound like a viable principle.

Some sentences are meaningless in a straightforward way, such as ungrammatical sentences or sentences like “Twas brillig and the slithy toves did gyre and gimble in the wabe”. Into this category falls the positivist’s favorite example of meaningless metaphysics, Heidegger’s “Nothing noths”. The problem here stems not from unverifiability but from other kinds of linguistic defect—and no proposition is accordingly expressed (unless we stipulate a sense for the problematic verb “noths”). Other sentences arguably fail to express verifiable propositions, for example “God exists”; but to call them meaningless appears far-fetched. The only reason “God exists” is unverifiable is that it expresses a proposition that is unverifiable; but then it is meaningful in virtue of expressing that proposition. The problem for the positivist is that no sentences fall between these two possibilities: no sentences are both unverifiable and meaningless—simply because to be unverifiable requires a proposition to have that property. Any sentence that fails to be verifiable because it fails to express a proposition at all will be so for reasons other than its unverifiability, say by being ungrammatical. Such sentences are unverifiable only in the entirely trivial sense that a brick is unverifiable: it is simply not the kind of thing that could be verified. A sentence can be unverifiable in the non-trivial sense only if the question of its verifiability can arise, but that requires an expressed proposition to be a candidate for verifiability. So the sentence must be meaningful after all.

Nor can we say that a proposition is meaningful if and only if it is verifiable (or falsifiable), since it is a category mistake to call a proposition meaningful or meaningless. A proposition has meaningfulness built into it (it is a meaning). Sentences are meaningful in virtue of expressing propositions, and these propositions can be verifiable or unverifiable; but they cannot express propositions without thereby being meaningful—and this is what they need in order to be verifiable or not. Indeed, we should not speak of sentences as verifiable at all, unless this is simply short for “expresses a verifiable proposition”–in which case the problem with the positivist’s principle is evident straight off. Expressing an unverifiable proposition is a way of being meaningful, not meaningless. Intuitively, we can only know that a sentence is unverifiable if we know what it says, but if it says something then it must be meaningful. Positivism thus rests on confusion between sentences and propositions–bearers of meaning and bearers of verification.

Colin McGinn

The Value of a Life

June 4, 2021/0 Comments/in Uncategorized/by Colin McGinn

The Value of a Life

It is natural to think that the value of a life depends on the nature of that life. The value of a life is internal to it. It depends on what happens to the individual, what he or she accomplishes, what he or she is. But this way of thinking depends on an assumption of uniqueness—to the effect that the individual has no duplicate. Suppose instead that you have a precise duplicate living somewhere, an individual who is exactly like you physically and mentally. If you accomplish something, so does your duplicate; there is nothing you can do or feel or think that your duplicate cannot do or feel or think. If you die tomorrow your duplicate will carry on, living a life exactly like yours. What if you have a million such duplicates dotted all over the universe? There is no shortage of people sharing whatever it is that characterizes your life: tokens of your type exist in abundance. When you die no one will be able to say, “They broke the mold with that one!” Whatever you were doing one of your duplicates could step in and do it. There is nothing unique about you, nothing irreplaceable, nothing special—people like you are a dime a dozen. Given suitable arrangements, no one would even notice your absence, not even your spouse.

But what about your value to yourself: does that also depend on the contingent fact of uniqueness? I fear so: it will be reduced by the existence of duplicates– you will value your life less than you would if you had no duplicates. For you will see that there is nothing uniquely valuable, objectively speaking, about your individual life, however valuable it may be as a type. [1] You may not want to die considered as an individual, but you have to admit that you are not contributing anything that no one else can contribute. Part of the value of your actual life is what you uniquely are, but if we abolish uniqueness that part is no more. Uniqueness contributes to the value of a person’s life, but uniqueness is not a necessary truth. In some possible worlds you are as common as dirt; in those worlds your life is less valuable than it is in the actual world.

We must conclude, then, that the value of a life depends, partly at least, on facts that lie outside the confines of that life—on who else exists. Compare species: it is worse if a qualitatively unique species goes extinct than it is if a species with a biological duplicate goes extinct. Suppose two distinct species of birds converge on the same phenotype after millions of years of evolution from a remote common ancestor: the intermediate species go through a different evolutionary history, but end up in the same place. We would say that they are distinct species, but they are qualitatively indistinguishable. If one goes extinct, the other remains. Surely this is less bad than a qualitatively unique species going extinct. Uniqueness matters to value. Similarly, the value of a human life depends on what other lives there are; it is not entirely internal to the individual life. The value of your individual life can be undermined by the existence of people just like you. It is less of a tragedy if you die in a world in which there are others similar to you.

[1] The token may have value qua token, but it will not have as much value if it is merely one token of a multiply instantiated type.

The Value of Modal Knowledge

June 4, 2021/0 Comments/in Uncategorized/by Colin McGinn

The Value of Modal Knowledge

As reflective rational beings, we tend to assume that knowledge of necessity has a special kind of value. Think back to when you first discovered that necessarily 2 + 2 = 4: didn’t you experience this discovery as a kind of revelation—as deep, interesting, and even thrilling? Not only does 2 added to 2 give 4 as a matter of fact, but this could not be otherwise—at any other time, for any other kind of thinking being, in any possible world. It may be useful and informative to discover that there happens to be a cat in the room next door, but it is a discovery of another magnitude that mathematical truths are necessary truths. Modal knowledge strikes us as uniquely valuable and profound—more so than non-modal knowledge of what is actually the case (even mathematically). In philosophy we seek it with particular ardor. But why is that? Why do we find knowledge of necessity so deep and exciting?

One possible answer is that necessary truths are general or universals truths, while contingent truths are particular truths. Thus if a truth is necessary it is true in all possible worlds, while if a truth is merely contingent it is true only in some possible worlds. And universal statements are just logically stronger than existential statements—they entail more. It is more valuable to know a necessary truth because it has more general scope—intuitively, it says more. However, we don’t generally accord universal statements special value compared to singular or existential statements—as in “All the coins in my pocket are silver” versus “Some of the coins in my pocket are silver”. Nor do we reserve special esteem for knowledge of what is true at all places or for all times—unless this reflects a necessary truth. It is not universality as such that has value but universality over logical space, i.e. necessity. The truth of a universal quantification is not itself a reason to prize modal knowledge to the degree that we do.

A quite different suggestion invokes our faculty of knowledge: it is not the modal proposition in itself that is valuable but the faculty by which we know it. We are special not the necessary truth itself. For it is not given to every knower to know necessary truths: you have to be a special kind of being to know such truths. Animals, we may surmise, do not have knowledge of necessary truths, even if they have other kinds of knowledge. Nor do human children have such knowledge until they reach the requisite stage of intellectual maturity. As animals and children may be said to experience lower pleasures not higher pleasures, so they may be said to possess lower but not higher knowledge. They lack Reason or Insight or Intuition or Understanding. Thus modal knowledge is a proof of our unique elevation as knowing beings. However, flattering though this theory may be, it fails to identify the source of value we seek. Let’s accept that we are epistemologically special in virtue of possessing modal knowledge: why does that show that modal knowledge itself is especially valuable? We need to know what it is about the object of such knowledge—what it is that is known—that deserves special esteem. No doubt we are also special for having perceptual knowledge, given that this depends on a highly evolved and sophisticated cognitive system, but we don’t think that perceptual truths themselves (e.g. “It’s raining now”) are especially valuable objects of knowledge. Nor do we accord non-modal knowledge of arithmetic the same status as knowledge of the necessity of arithmetical truths, even though both are beyond the reach of animals and infants. There is something about necessity itself that strikes us as especially worth knowing—as epistemic gold. It is the fact not the faculty that invites admiration.

I think the right answer has an Aristotelian complexion. Knowledge of necessity is knowledge of essence quaessence. It is knowledge of what makes a thing the thing that it is—its nature and definition. This is to be contrasted with knowledge of contingency, which concerns what merely happens to be the case, with what is true by chance. What is contingently true of an object does not penetrate to its inner being, but only to its accidental characteristics. For example, it is only contingently true that I am wearing spectacles—in no way does that define my identity—but the fact that I have a particular brain is integral to being the person I am. Thus when we know a necessary truth we are at the heart of a thing’s being, not merely hovering at its ontological periphery. So knowledge of necessary truths confers knowledge of a thing’s essential nature—its what-it-is-to-be, as Aristotle would put it. This is deeper knowledge than knowledge of the chance properties of an object, those it could easily have lacked. Chance, accident, and contingency—these are the marks of everything that is external to the core being of a thing. We value modal knowledge, then, because we value knowledge of a thing’s intrinsic essential nature. Modal knowledge is ontologically penetrating.

This way of thinking posits two ontological levels to reality–a deep level and a superficial level. At the superficial level, we have the contingent and accidental—that which just happens to be true of a thing but could easily have been otherwise. At the deep level, we have essences and natures—that which could not be otherwise. The fact that we value modal knowledge as we do shows that we recognize the existence of these two levels; in particular, that we accept the existence of a level of reality that goes beyond what merely happens to be. It is a level of permanence, fixity, and immutability. This Platonic-sounding level contrasts with the transitory and ever-changing level, that which may be wiped away and abolished. It is the contrast between chance and necessity. Knowledge of the deeper level of reality strikes us as more valuable than knowledge of the more superficial level. It is harder to obtain such knowledge, and when we obtain it we have a more penetrating insight into reality. Any fool can see at a glance that 2 eggs plus 2 eggs equals 4 eggs, but it takes insight to grasp that it is in the very nature of the number 2 that when added to itself it must equal 4. We could reasonably paraphrase “Necessarily 2 + 2 = 4” as “It is in the very nature of the number 2 that doubling it equals 4”. To know this truth we need to have insight into the essential nature of numbers. We are dealing with a metaphysical truth not just an arithmetical truth. We value modal knowledge because we value metaphysical knowledge, which the concept of necessity enables us to possess.

By way of confirmation of this suggestion notice what happens if we set out to deflate modal knowledge. Suppose we insist that all necessity is just a reflection of conventional linguistic rules, with no bearing on extra-linguistic reality. Then modal knowledge will boil down to knowledge of linguistic conventions and intentions to stick by them. In that case, any special value thought to reside in modal knowledge evaporates, along with the notion of de re necessity. Such a deflationary position is calculated to be revisionist, and is felt to be so. We feel that something valuable has been taken away from us—the idea of reality as composed of things with substantial objective essences, which we might discover. It is the same with nomological necessity: here too the notions of law and causation suffer ontological demotion and epistemological deflation if we decide to restrict ourselves to non-modal concepts (“constant conjunction” and the like). The case is comparable to anti-realist views in ethics and aesthetics. The way we spontaneously understand these domains has been attacked, and we are left with a mere husk of the original article. The disappointment we feel is an indication of our initial valuation: we thought we were dealing with something deep and important, but we have been brought to see that there is much less to it than meets the eye. That is: our intuitive sense of the importance of modality rests open a robustly metaphysical conception of its place in the world. We normally take it that necessity is written deep into the nature of things, and hence deserves our attention and respect; but we may be persuaded (wrongly, I would say) that necessity is nothing but revocable human convention. Our habitual starry-eyed and awestruck estimation of modality has been punctured. Thus we value modal knowledge because we believe (rightly) that it reveals deeps truths about the world. It couples with metaphysical knowledge.

The question of the value of modal knowledge has an immediate relevance to the value of philosophy. For it is a traditional and powerful view that philosophy is precisely concerned with the discovery of essences quaessences. Suppose that view to be true: then philosophical knowledge is characteristically modal knowledge—knowledge that something is necessarily the case. Accordingly, philosophical knowledge has the value attaching to modal knowledge, which puts philosophy in a special place epistemologically. Not to put too fine a point on it, it makes philosophical knowledge superior (in one respect anyway) to scientific knowledge or historical knowledge or any knowledge that is of non-modal propositions. Philosophy provides knowledge of essence qua essence, while other branches of inquiry provide only knowledge of what is in fact the case—knowledge of the actual world not knowledge of all possible worlds. For many of us, that is why we went into philosophy to begin with—because it offers a uniquely deep insight into reality, extending across all of logical space. It tells us how things must be, not merely how things happen to be.