Evolution by Nutritional Selection

Animals need food. They cannot survive and reproduce without it. They therefore have adaptations that ensure that enough food is consumed: traits that enable them to find food and consume it. This is not selfishly confined to the individual animal; animals also procure food for their young, often going without themselves. You have heard about the survival of the fittest; well, this appetite for food is the survival of the fattest—the fullest, the foodiest. The animal that eats well lives the longest and produces the most babies (which it feeds). Evolution by natural selection revolves around food. It is the original biological imperative: eat, eat, eat! Eat or die. And it is constant (unlike sex and reproduction)—the hunger, the searching, the gathering, the consuming. Animals are basically eating machines. They do it in different ways, but they all do it—there are no non-eating species. It is a biological universal (unlike sex and horns). For animals need energy and energy comes in the form of food (originally from the Sun). Animals need fuel (the Sun is their gas tank). The most successful animal, accordingly, is the best eater—the one that always has food available and is able to digest it effectively. This animal will be the most prolific propagator. Evolution is by nutritional selection (not so much sexual selection or aggression selection or intelligence selection).

We can put all this in terms of genes. The selfish gene is the greedy gene—the gluttonous gourmet gene. The greedy gene likes to be well fed; not the individual animal, mark, but the gene itself. Because the selfish gene is equally concerned about identical genes in other bodies, especially offspring. The greedy gene will help build a mother that feeds its descendant genes—it will produce good and plentiful milk for the babies that carry that gene. In mating the greedy gene will favor mates that will best feed its offspring; it will select a mate that brings home the bacon. The male will make the best food gatherer and the female will produce the finest milk. A good parent is one that puts food on the table. Siblings will fight for food, also following genetic imperatives. The genes are food-obsessed because food provides the indispensable fuel for genetic reproduction. A selfish gene with no appetite for food will not survive long in the gene pool.[1] It must build bodies that are ravenous for food and skilled at getting it. Evolution has been perfecting food consumption from its earliest days—from hunting to digesting. Find the food, swallow it down, then effectively digest it (then excrete the remains). The whole ecosystem of an animal (and its genes) is a food ecosystem. Animals copulate, compete, and fight—but mainly they eat. When an animal is described as territorial that is a misnomer; the animal (or its genes) doesn’t care about owning property—it cares about the food that is found on that property. Not territory but the accompanying comestibles; if the animal could get the food without the area it is found in, it wouldn’t bother defending that territory. Who wants to wander round all day defending a piece of land (you can’t eat that)? People used to say that nature is red in tooth and claw; maybe so, but it is also mashed in mouth and belly. Saliva not blood, and violent in the service of eating (as well as mating). Life on earth is all about getting enough to eat.

What about humans? We are a very successful species, probably the most successful in terms of world domination. We are also accomplished eaters: we produce our own food, of all kinds, distribute it, and devote ourselves to consuming it. We have a food economy, restaurants, chefs, TV programs, the works. We are fat to the point of ill-health (is there an obesity problem in any other animal species?). Our huge population growth is made possible by our food productivity. We are not held back by food shortages. We have a food-oriented brain. It is sometimes supposed that we got rid of Neanderthals by making war on them, but perhaps we just out-ate them. We had a better food delivery system. We have taken food to an advanced level, far beyond any other species. We have made food an art and a science. We actually cook (fire was surely crucial in achieving food supremacy). Our culture is centered around food. We now live to eat while other animals eat to live (and do what exactly?). We are the foodie species. We eat everything and we put a lot of thought into it. Our hands are well designed for food gathering and preparation, as well as actual eating. Our tools are often food related. Without our human hands we might not have become so expert in the business of food. Thus, our bipedal gait is a pre-adaptation for food dominance, freeing up the hands for food activity. The hands are perfect instruments for food gathering, food preparation, and food insertion. We even supplement them with utensils (very rare in the non-human world). We go on dinner dates to fancy restaurants with the express purpose of seeing how potential mates conduct themselves around food. Marriage is all about providing and sharing food. Food and sex are closely intertwined. There is also the matter of children: who will be better at feeding them? Back in the day the ideal man would be healthy and strong, good at providing food, while the ideal woman would be good at feeding babies. We might speculate that the attraction of large breasts has something to do with providing plentiful milk for babies; those selfish greedy genes will have their beady eyes on the most nourishing breasts. Big muscles, big breasts—plenty of good grub for all concerned. The naked ape is a hungry ape and wants to be assured of a reliable food supply. Fear of food shortages is a constant anxiety, given the ruthlessness of nature, so you want all the information you can get with regard to a potential mate. Mate selection is nutritional selection, just like natural selection. Animals are selected according to their nutritional fitness. A hopelessly skinny half-starved animal will not do well in the battle for survival and reproduction; it’s survival of the fattest out there. The presence of fat is a guarantee that you won’t starve to death. Given that obesity isn’t generally a problem in the animal world, fat is better than thin, ceteris paribus.

What is an animal? What are the fundamental mechanisms of evolution? These are clearly interconnected questions. One image has it that animals are violent power-hungry brutes out for domination over their fellows; this image reflects social conditions in capitalist Victorian England. Another image views animals as filthy crude pre-human beasts wallowing in squalor; this perhaps reflects the condition of peasants in the Middle Ages, as seen through the eyes of the upper classes. A third image depicts them as libidinous creatures perpetually primed for sex; this picture seems to have taken hold during the 1960s (see Desmond Morris’s The Naked Ape). The present image, derived mainly from TV documentaries, is that of an anxious creature always searching for food—a kind of sentient eating machine. This animal is long-suffering but driven—driven to spend its days in the pursuit of something to eat. I think this view is less anthropocentric than the others: animals really are victims of a mindless evolutionary process that compels them to seek out food or die. They are tragic beings, though in many ways admirable—not violent filthy sex maniacs. Even the apex predators are caught in a cycle of deprivation and lucky relief from starvation (like many unfortunate humans). They eat or die. That is the basic fact of animal life.[2]

[1] The same line of reasoning applies to memes, but I won’t go into this. All replication requires fuel of some sort.

[2] Life on Earth is perhaps unusual compared to other inhabited planets. We are the only civilized eaters on Earth, but on other planets there may be many species with our degree of culinary sophistication (see Star Wars for documentation). There may be even more expert eaters elsewhere with greater planetary domination (galactic domination). The food might be better and more plentiful in these places. The well-fed aliens might have bigger brains, fleeter feet, greater flexibility, and superior morals. We are at the culinary pinnacle here on Earth, but so what?

Counterfactual Empiricism

Classical empiricism is the doctrine that all knowledge is knowledge of impressions: you know what, and only what, you have perceived with your senses. This doctrine runs into trouble with things you know but have not perceived—concepts of the unperceived. It would appear to imply that you can’t have concepts of, and knowledge about, atoms and bacteria (among other things). What I am calling counterfactual empiricism seeks to avoid this problem while remaining true to empiricist principles. It says we can have knowledge about things we can imagine seeing (hearing, tasting, etc.). I can imagine seeing bacteria and atoms, since they are just smaller versions of what I actually see all the time (or so we can suppose). I know what it would be like to see an atom or bacteria. Hence, I have the concept and can grasp the meaning of the terms. The doctrine, then, is that all knowledge is of actual or possible impressions—what I would see if I could see. Knowledge is of what I can envisage seeing. This seems an improvement on the classical, more restrictive, doctrine. In what follows I will confine the discussion to seeing and ignore the other senses, though the same points apply mutatis mutandis. I will be particularly concerned with the concept of mind.

Counterfactual empiricism is not free of difficulty: for there are apparently many things that cannot be seen, no matter how counterfactually. A partial list would be the following: numbers, values, universals, logical forms, propositions, causation, necessity, infinity, selves, and minds. Do you know what it would be like to see any of these things? Can you envisage (imagine) seeing a number, an ethical value, a Platonic form, a logical form, causal or logical necessity, an abstract proposition, an infinite collection, a self, a mind? These don’t seem like the kinds of thing anyone could see, and hence imagine seeing. But perhaps we can partially imagine seeing them; some sort of sensory content is associated with them. Perhaps we can imagine seeing a number by imagining seeing a numeral (we actually see those). Perhaps we can have a mental image of the color red considered in itself. Perhaps a logical form looks remarkably like a written sentence. Perhaps necessity looks rather like a man pushing a cart. Perhaps a self looks like a glowing point. All these seem pretty farfetched, though not entirely devoid of intuitive appropriateness. Perhaps exceptionally imaginative people have quite vivid images of such things; they may say they know just what these things would look like if they could be seen. And wouldn’t this be a valuable form of knowledge—knowledge of how thing would look if they could be seen? Even if it is impossible that they could be seen, this is how they would look if seen; we can at least imagine that. Can’t God imagine what a number would look like if it were seen—even if he could never see it? It is possible to imagine impossibilities (Escher drawings). True, we cannot imagine nonsense—we can’t imagine seeing colorless green ideas sleeping furiously. But it isn’t nonsense to suppose that numbers can be seen—just metaphysically impossible. It isn’t contradictory. Nor is it like envisaging seeing slithy toves gimbling in the wabe. There can be difficult cases in which it is hard to decide whether something can be imagined being seen.

Could the mind ever be seen, and could we imagine this? It can be introspected, but could it be seen by the visual sense? If so, what would it look like? Consider this question: could sounds be seen, and if so, what would they look like? Well, we could clearly hook up sound waves in the atmosphere to our visual cortex and produce visual impressions as a result of auditory stimuli. The auditory inputs simply recruit the optic nerve and project to the visual cortex: the sound waves thus cause visual sensations. But could these sensations have a content that correctly represents the nature of sound waves? I don’t see why not: the sensations are as of waves in a medium, somewhat like seeing ocean waves. Phenomenologically, the sensations are not like ordinary auditory sensations, but they are veridical (as auditory sensations are not), since sound waves arewaves. Sound waves can be experienced with the ears and they can be experienced with the eyes; it is possible to see them, and possible to imagine seeing them. You might get hooked up tomorrow. We know what it would be like to see sound waves, even though we never do. The question I want to ask is whether the mind is like that: we never in fact see the mind, but could we? Could we be hooked up that way—and if we were, what would the mind look like? Someone might say there is no problem, since the mind is the brain and we can see the brain, even if we never do in fact. We could hook the brain up to the visual system in such a way as to produce visual impressions of the brain (or taste and smell impressions come to that). But that is not interesting and presupposes materialism. So, what would the mind look like under immaterialism? It might be said that it would look like a river, because consciousness is like a river; but this too is uninteresting and still too materialistic. Would it look like a cloud? Closer, but still wrong. Would it look like a fireworks display? Would it look like the Sun, or a starry night, or a kaleidoscope? Hmmm. Perhaps we can be more specific: what would a belief look like if it could be seen? Here we might envisage a kind of bridge between one thing and another, corresponding to a believer and a proposition, with the proposition reaching out to a distant landscape.[1] That doesn’t sound too far off; it gives one hope. What about Martians with superb imaginations that can fill in the details and produce an impressive visual impression of a belief? What if we really worked on it, recruiting top brain scientists? It doesn’t sound out of the question. After all, the mind is an empirical entity with definite characteristics, so all we need to do is attach a sensor to it that feeds into a visual system—and (voila!) visual impressions of a mind. We would see thoughts, pains, reasoning, emotions, etc. Yet we are very far from doing this—very far indeed. This is a kind of knowledge of the mind that we are nowhere near possessing, though apparently possessable. The mind does look a certain way if you have eyes that can see it. In fact, it now has a certain look—how it would look if you could see it (which in principle you could). It is disposed to look a certain way, where this disposition is grounded in its intrinsic nature. It has, as it were, a certain shape or form, a certain mode of perceptual presentation. Right now, it is in possession of such a mode of presentation, in addition to its introspective mode of presentation. We can’t imagine how it would look now, except very rudimentarily, but there is presumably a fact of the matter. There might even be a preferred way it should be seen to maximize veridicality.

Now I want to connect these reflections to the mind-body problem: would we be nearer to solving that problem if we knew what the mind looks like? We would have a visual representation of it, which we signally lack now. This might be brought together with our visual representation of the brain, so that they can be placed side by side. As things stand, we have no such opportunity; but if we had conceptions of mind and brain of like nature, we might be in a better position to solve the mind-body problem. Indeed, we might already have solved the problem. We might say, “Oh, now that I know what the mind looks like, I can see how it relates to the brain!” When we had no vision-based conception of the mind, we were at a loss to see the connection, but now we can compare like with like and see (literally) how it all fits together. It would be like comparing macro conceptions of matter with micro conceptions, both of which are vision-based, and seeing no problem of emergence. The problem is that we don’t have a vision-based conception of the mind; hence, the sense of mystery. The mystery might disappear if we had the right conception of mind, i.e., one continuous with our conception of the brain. Or at least we might have a sound basis to reason from, do experiments, etc. If this is so, we now know what it would take to solve the mind-body problem—a visual representation of the mind. And wouldn’t this solve the other minds problem at the same stroke, given that we could actually see the other’s mind not just infer it from behavior? If counterfactual empiricism were true of the mind, then we would be within reach of solving these problems. Of course, we are very far from being able to see minds or even to imagine what it would be like to see them. Classical empiricism always had problems accounting for our mental concepts (“ideas of reflection”) because we don’t sense our minds with our five senses; it would have done better to move towards counterfactual empiricism, accepting that our concept of mind is a work in progress waiting upon advances in brain science and a cure for mind-blindness.[2]

[1] Another example would be mental modularity: would the modular mind look compartmentalized if we could see it? Would it look a bit like a Lego set or a car engine? Would we see the divisions and distinctions in the modules where now they are abstractly understood? If we saw intentionality, would it look like a wire or a laser beam? Would pain look like a jagged edge or an erupting volcano? Or would these things look like nothing we have ever seen before but still look like something?

[2] I am well aware how far out on a limb I have gone in this paper—seeing the mind indeed! But in philosophy (and sometimes science) out on a limb is where you want to be—that’s where the best fruit is. In some possible worlds it might seem extraordinary to people, given their senses, that the mind is not perceptible to some unfortunate souls. In this world children draw pictures of the mind and there are photos of it in books. For these perceptive people we are lamentably mind-blind.

Existence Explained

Probably the most infuriating question in philosophy is the nature of existence. I have racked my brains over it lo these many years and come up with nothing.[1] Now at last I think I have found the solution, and it’s not what you would think. It fits the facts. So, right here, right now, I will give you the solution—dim the lights, Geoffrey. But first a quick reminder of all the dud solutions, the runners-up, the heroic also-rans (let’s have a round of applause for them): to be is to be the value of a variable (or the reference of a pronoun); to exist is to have the second-order property of instantiating a property; to exist is to have an unanalyzable first-order property of existence; to exist is to be an occupant of space; to exist is to be an idea in the mind of God; to exist is to be spoken of in a text; to exist is to have causal powers; to exist is to be an object of thought; to exist is to be a sense-datum; to exist is to be socially constructed; to exist to be not imaginary; to exist is to be material; to exist is to be mathematical; to exist is to be useful. A rum lot really. Hardly worth refuting. So, let’s get to the winner, the star of the show, the incontestable champ.

And the winner is: to exist is to be detachable. Yes, I know it sounds a bit bathetic, but stay with me awhile, be patient. The intuitive idea is that an existent thing is a thing that can be detached from other things—separated, disconnected. A non-existent thing is a thing that cannot be detached from other things. This is intended as a statement of necessary and sufficient conditions, a classical conceptual analysis. We are not pulling any punches or speaking metaphorically. This is what existence is. You need to see the analysis in action to appreciate its merits. What is the paradigm of an existent thing? Material objects, of course (the paradigm of our modern sensibility anyway—not the gods or anything like that). Perceptible objects in space—substances. They can be separated from each other, detached, disconnected. They come to us in conjunction with other things, but they can be physically moved and detached in thought. They don’t depend on anything else to be what they are. The table is detachable from the chair, even though they are next to each other in actuality; they will still be there if separated spatially. They are also detachable from the perceiver. They are independent things (the old definition of a substance). To think about one, you don’t have to think about the other. Contrast these things with imaginary objects: here you can’t detach the perceiver; no perceiver, no object. If no hallucinating perceiver, then no pink rats. Pink rats are necessarily attached to perceivers (as things are), unlike brown ones. The latter exist, the former don’t.

Now consider some intermediate cases, starting with universals. Plato thinks they are detachable from particulars: this is what constitutes their clear existence for him. Aristotle disagrees, so universals for him have less than complete existence—perhaps no existence at all. Fictional entities are not detachable from the minds of their creators, so their existence is in doubt; some say they are the paradigms of the non-existent (even more so than hallucinated objects). Meinongian objects seem indissolubly connected to minds (e.g., the golden mountain), so their existence is questionable, though a dose of subsistence is sometimes allowed. Then we come to some hard cases: numbers, mental states, ethical values, space, time, God, meaning, events, shadows, holes, shapes, concepts, selves. All of these have had their existence rudely denied: the question is why. Is the number 2 separable from other things—other numbers or mathematical minds? Could it exist on its own? If yes, it indisputably exists; if not, its existence comes into question. Does a particular thought exist? That depends on its detachability from other thoughts and from the brain. Holism undermines individual existence, and so does inseparability from the brain (materialist reductionism). Ethical values strike people as not detachable from natural facts, e.g., societal norms, so their existence comes into doubt. Ethical realism is better off under ethical autonomy (ethical truth before moral agents). Space looks in danger of disappearance if it cannot be detached from the matter it contains. Time starts to look wispy if events are removed. God cannot survive dependence on human belief. Meaning becomes existentially questionable if it cannot be detached from words—a mere shadow of language. Events lose all substance if they are constituted by objects and properties and are incapable of existence without them. Shadows are too attached to the bodies that cause them to be accorded genuine existence. Holes cannot be detached from what they are holes in. Shapes go up in smoke if detached from physical things, or are thought to. Concepts are found wanting if not detachable from language. Selves can have no being if they cannot be disconnected from bodies and mental states. In all these cases, the applicability of our basic concept of existence is called into question: the more attached a thing is, the less real. Those who resist these conclusions do so by insisting that the questioned items are detachable; they picture worlds in which the items exist autonomously. They can exist in splendid isolation! I needn’t go into all this; the point is that existence turns on the detachability question. If it turns out that material objects are really constructions from sense-data, then they too will have their existence queried. If it turns out that mental states are completely dependent on brain states, then they will be in peril of being relegated to the ranks of nonbeing. The central point of the concept of existence is that the thing in question can exist separately: the more detachable, the more real. This is why the primary cases are material objects in space and imaginary objects in minds: the former can exist in the absence of minds, but the latter cannot. The idea of existence is closely linked to the idea of objectivity, and objectivity is a matter of detachability from the subjective perspective. We say something is merely subjective when it doesn’t really exist. Realism is typically an affirmation of detachment from human concerns. Anti-realism is a claim of attachment to human concerns.

One nice feature of this theory is that it applies to any category of object: we don’t end up favoring one kind of object over others—physical, mental, or abstract. The definition covers all these cases. It also prescinds from epistemological considerations; it is purely ontological. And it brings out a latent relational aspect of existence: for x to exist is for x to be detachable from y. It thus provides a genuine analysis not just a trivial synonym (“to exist is to have being”). We have fashioned a concept that encapsulates the facts of detachability. If I want to say that pink rats are not separable from a perceiver’s mind, I simply say they don’t exist (are not real). If asked to explain what I mean, I say “Pink rats are inseparable from the perceiver’s mental state and dependent on it”. The word “exists” is very much a catch-all term, topic-neutral, quite abstract; and also, essentially contestable. It is a philosopher’s term with a theoretical meaning (more so than “true”). I like the definition because it injects new content into discussions of existence and doesn’t leave us with nothing substantive to say. It gets at the deep structure of the concept, lying just beneath the surface. Is there anything better out there?[2]

[1] See my Logical Properties (2000), chapter 2, as well as several essays on this blog. I came up with the present theory by going through every possible theory I could think of until something gelled.

[2] Why has it not been thought of before? Because of a tacit commitment to empiricism (the usual culprit): there is a hankering for something close to the perceptual—an existence sense-datum. But the concept of existence is a highly intellectual concept—it connotes an abstract structure. It involves a quasi-geometrical modal structure: the mind has to detach in thought one thing from another in an act of modal separation—a possible world, in effect. The concept of existence is a modal concept in that it requires conceiving of a possibility—this without that. For example, for me to recognize that a part of an object exists I have to construct a possible world in which the part is detached from the whole and considered by itself. This is nothing like seeing red. I doubt that any animals have this concept. We also have the difficult task of deciding whether one thing can exist without another—whether, say, a property can exist without a bearer. The concept is much more complex and problematic than traditional theories have realized.