Consilience: The Unity of Knowledge

Here is how reductionism works most of the time, as it might appear in a user's manual. Let your mind travel around the system. Pose an interesting question about it. Break the question down and visualize the elements and questions it implies. Think out alternative conceivable answers. Phrase them so that a reasonable amount of evidence makes a *clear-cut* choice possible. If too many conceptual difficulties are encountered, back off. Search for another question. When you finally hit a soft spot, search for the model system—say a controlled emission in particle physics or a fast-breeding organism in genetics—on which decisive experiments can be most easily conducted. Become thoroughly familiar—no, better, become obsessed—with the system. Love the details, the feel of all of them, for their own sake. Design the experiment so that no matter what the result, the answer to the question will be convincing. Use the result to press on to new questions, new systems. Depending on how far others have already gone in this sequence (and always keep in mind, you must give them complete credit), you may enter it at any point along the way. Followed more or less along these lines, reductionism is the primary and essential activity of science. But dissection and analysis are not all that scientists do. Also crucial are synthesis and integration, tempered by philosophical reflection on significance and value. Even the most narrowly focused researchers, including those devoted to the search for elemental units, still think all the time about complexity. To make any progress they must meditate on the networks of cause and effect across adjacent levels of organization—from subatomic particles to atoms, say, or organisms to species—and they must think on the hidden design and forces of the networks of causation. *Quantum* physics thus blends into chemical physics, which explains atomic bonding and chemical reactions, which form the foundation of molecular biology, which *demystifies* cell biology.

- quantum: a very small quantity of electromagnetic energy - demystify: demystify something to make something easier to understand and less complicated by explaining it in a clear and simple way

*Astronomy*, biomedicine, and physiological psychology possess all these criteria. *Astrology*, *ufology*, creation science, and Christian Science, sadly, possess none. And it should not go unnoticed that the true natural sciences lock together in theory and evidence to form the in-eradicable technical base of modern civilization. The pseudosciences satisfy personal psychological needs, for reasons I will explain later, but lack the ideas or the means to contribute to the technical base.

- Astronomy: the scientific study of the sun, moon, stars, planets, etc. - ufology: the study of UFOs - Astrology: the study of the positions of the stars and the movements of the planets in the belief that they influence human affairs

I mean no disrespect when I say that pre-scientific people, regardless of their innate genius, could never guess the nature of physical reality beyond the tiny sphere attainable by unaided common sense. Nothing else ever worked, no exercise from myth, revelation, art, trance, or any other conceivable means; and notwithstanding the emotional satisfaction it gives, mysticism, the strongest prescientific probe into the unknown, has yielded zero. No shaman's spell or fast upon a sacred mountain can summon the electromagnetic spectrum. *Prophets* of the great religions were kept unaware of its existence, not because of a secretive god but because they lacked the *hard-won* knowledge of physics.

- Prophet: a person sent by God to teach the people and give them messages from God - hard-won: that you only get after fighting or working hard for it

SCIENTIFIC EVIDENCE IS *accretionary*, built from blocks of evidence joined artfully by the blueprints and mortar of theory. Only very rarely, as in the theories of natural selection and relativity, does an idea change our conception of the world in one quantal leap. Even the revolution of molecular biology was accretionary, building upon but not fundamentally altering physics and chemistry.

- accretion: a layer of a substance or a piece of matter that is slowly added to something

THE INTELLECTUAL THRUST of modern science and its significance for the consilient worldview can be summarized as follows. In the ultimate sense, our brain and sensory system evolved as a biological *apparatus* to preserve and to multiply human genes. But they enable us to navigate only through the tiny segment of the physical world whose mastery serves that primal need. Instrumental science has removed the handicap. Still, science in its fullness is much more than just the *haphazard* expansion of sensory capacity by instruments. The other elements in its creative mix are the classification of data and their interpretation by theory. Together they compose the rational processing of sensory experience enhanced by instrumentation.

- apparatus: the tools or other pieces of equipment that are needed for a particular activity or task - haphazard: with no particular order or plan; not organized well

Advice to the novice scientist: There is no fixed way to make and establish a scientific discovery. Throw everything you can at the subject, as long as the procedures can be duplicated by others. Consider repeated observations of a physical event under varying circumstances, experiments in different modes and styles, correlation of supposed causes and effects, statistical analyses to reject null hypotheses (those deliberately raised to threaten the conclusion), logical argument, and attention to detail and consistency with the results published by others. All these actions, singly and in combination, are part of the tested and true *armamentarium* of science. As the work comes together, also think about the audience to whom it will be reported. Plan to publish in a reputable, peer-reviewed journal. One of the strictures of the scientific *ethos* is that a discovery does not exist until it is safely reviewed and in print.

- armamentarium: the medicines, equipment, and techniques available to a medical practitioner. - ethos: the moral ideas and attitudes that belong to a particular group or society

The *canonical* definition of objective scientific knowledge avidly sought by the logical positivists is not a philosophical problem nor can it be attained, as they hoped, by logical and semantic analysis. It is an empirical question that can be answered only by a continuing probe of the physical basis of the thought process itself. The most fruitful procedures will almost certainly include the use of artificial intelligence, aided in time by the still embryonic field of artificial emotion, to simulate complex mental operations. This modeling system will be joined to an already swiftly maturing neurobiology of the brain, including the high-resolution scanning of computational networks active in various forms of thought. Important advances will also come from the molecular biology of the learning process.

- canonical: included in a list of holy books that are accepted as genuine; connected with works of literature that are highly respected (hợp nguyên tắc, hợp với kinh điển)

S C I E N C E, *its imperfections notwithstanding, is the sword in the stone that humanity finally pulled*. The question it poses, of universal and orderly materialism, is the most important that can be asked in philosophy and religion. Its procedures are not easy to master, even to conceptualize; that is why it took so long to get started, and then mostly in one place, which happened to be western Europe. The work is also hard and for long intervals frustrating. You have to be a bit compulsive to be a productive scientist. Keep in mind that new ideas are *commonplace*, and almost always wrong. Most flashes of insight lead nowhere; statistically, they have a half-life of hours or maybe days. Most experiments to follow up the surviving insights are *tedious* and consume large amounts of time, only to yield negative or (worse!) ambiguous results. Over the years I have been *presumptuous* enough to counsel new Ph.D.'s in biology as follows: If you choose an academic career you will need forty hours a week to perform teaching and administrative duties, another twenty hours on top of that to conduct respectable research, and still another twenty hours to accomplish really important research. This formula is not boot-camp *rhetoric*. More than half the Ph.D.'s in science are stillborn, dropping out of original research after at most one or two publications. Percy Bridgman, the founder of high-pressure physics—no pun intended—put the guideline another way: *"The scientific method is doing your damnedest, no holds barred."*

- commonplace: done very often, or existing in many places, and therefore not unusual - tedious: lasting or taking too long and not interesting - presumptuous: too confident, in a way that shows a lack of respect for other people - rhetoric: speech or writing that is intended to influence people, but that is not completely honest or sincere - damnedest: do/try your damnedest (to do something): to try as hard as you can (to do something)

Logical positivism was the most valiant concerted effort ever mounted by modern philosophers. Its failure, or put more generously, its shortcoming, was caused by ignorance of how the brain works. That in my opinion is the whole story. No one, philosopher or scientist, could explain the physical acts of observation and reasoning in other than highly subjective terms. Not much has improved in the past fifty years. The mindscape is now under active exploration but still largely unmapped. Scientific discourse, the focus of logical positivism, comprises the most complex of mental operations, and the brain is a messy place at best even when handling the most elementary of ideas. Scientists themselves do not think in straight lines. They *contrive* concepts, evidence, relevance, connections, and analysis as they go along, parsing it all into fragments and in no particular order. Herbert Simon, a Nobelist who has devoted part of his career to the subject, says of the complexity of concept formation: "What chiefly characterizes creative thinking from more *mundane* forms are *(i) willingness to accept vaguely defined problem statements and gradually structure them, (ii) continuing preoccupation with problems over a considerable period of time, and (iii) extensive background knowledge in relevant and potentially relevant areas."*

- contrive: contrive to do something to manage to do something despite difficulties - mundane: not interesting or exciting

I had experienced the Ionian Enchantment. That recently *coined expression* I borrow from the physicist and historian Gerald Holton. It means a belief in *the unity of the sciences*—a *conviction*, far deeper than a mere working proposition, that the world is orderly and can be explained by a small number of natural laws. Its roots go back to Thales of Miletus, in Ionia, in the sixth century B.C. The legendary philosopher was considered by Aristotle two centuries later to be the founder of the physical sciences. He is, of course, remembered more concretely for his belief that all matter consists ultimately of water. Although the notion is often cited as an example of how far astray early Greek *speculation* could wander, its real significance is the *metaphysics* it expressed about the material basis of the world and the unity of nature.

- conviction: the act of finding somebody guilty of a crime in court; the fact of having been found guilty (sự kết án, kết tội) - speculation: the act of forming opinions about what has happened or what might happen without knowing all the facts - metaphysics: the branch of philosophy that deals with the nature of existence, truth and knowledge (siêu hình học, lý thuyết suông)

Nothing in science—nothing in life, for that matter—makes sense without theory. It is our nature to put all knowledge into context in order to tell a story and to re-create the world by this means. So let us visit the topic of theory for a moment. We are enchanted by the beauty of the natural world. Our eye is caught by the *dazzling* visual patterns of polar star trails, for example, and the choreography of chromosomes in dividing root tip cells of a plant. Both disclose processes that are also vital to our lives. In unprocessed form, however, without the theoretical frameworks of heliocentric astronomy and Mendelian heredity, they are no more than beautiful patterns of light.

- dazzling: so bright that you cannot see for a short time

With instrumental science humanity has escaped confinement and prodigiously extended its grasp of physical reality. Once we were nearly blind; now we can see —literally. Visible light, we have learned, is not the sole illuminating energy of the universe, as prescientific common sense *decreed*. It is instead an infinitesimal sliver of electromagnetic radiation, comprising wavelengths of 400 to 700 nanometers (billionths of a meter), within a spectrum that ranges from gamma waves trillions of times shorter to radio waves trillions of times longer. Radiation over most of this span, in wildly varying amounts, continually rains down on our bodies. But without instruments, we were oblivious to its existence. Because the human retina is rigged to report only 400-700 nanometers, the unaided brain concludes that only visible light exists.

- decreed: an official order from a ruler or a government that becomes the law - trillion: one million million

The third enabling precondition is what the physicist Eugene Wigner once called the unreasonable effectiveness of mathematics in the natural sciences. For reasons that remain *elusive* to scientists and philosophers alike, the correspondence of mathematical theory and experimental data in physics, in particular, is *uncannily* close. It is so close as to *compel* the belief that mathematics is in some deep sense the natural language of science. "The enormous usefulness of mathematics in the natural sciences," Wigner wrote, "is something bordering on the mysterious and there is no rational explanation for it. It is not at all natural that 'laws of nature' exist, much less that man is able to discover them. The miracle of the appropriateness of the language of mathematics for the formulation of the laws of physics is a wonderful gift which we neither understand nor deserve."

- elusive: difficult to find, define or achieve - uncannily: in a way that seems strange and is difficult to explain - compel: to force somebody to do something; to make something necessary

Such, I believe, is the source of the Ionian Enchantment: Preferring a search for objective reality over revelation is another way of satisfying religious hunger. It is an *endeavor* almost as old as civilization and *intertwined* with traditional religion, but it follows a very different course—a *stoic's* creed, an acquired taste, a guidebook to adventure plotted across rough terrain. It aims to save the spirit, not by surrender but by the liberation of the human mind. Its central *tenet*, as Einstein knew, is the unification of knowledge. When we have unified enough certain knowledge, we will understand who we are and why we are here.

- endeavor: an attempt to do something, especially something new or difficult - intertwined: if two or more things intertwine or are intertwined, they are twisted together so that they are very difficult to separate - stoic: able to suffer pain or trouble without complaining or showing what you are feeling - surrender: to admit that you have been defeated and want to stop fighting; to allow yourself to be caught, taken prisoner, etc. - tenet: one of the principles or beliefs that a theory or larger set of beliefs is based on

Few claims in science, and particularly those *entailing* concepts, are accepted as final. But as evidence piles upon evidence and theories *interlock* more firmly, certain bodies of knowledge do gain universal acceptance. In seminar *patois*, they ascend a scale of credibility from "interesting" to "suggestive" to "persuasive" and finally "compelling." And given enough time thereafter, "obvious."

- entailing: to involve something that cannot be avoided - interlock: interlock (something) (with something) to fit or be fastened firmly together - patois: a form of a language, spoken by people in a particular area, that is different from the standard language of the country

Then I discovered evolution. Suddenly—that is not too strong a word —I saw the world in a wholly new way. This *epiphany* I owed to my mentor Ralph Chermock, an intense, chain-smoking young assistant professor newly arrived in the provinces with a Ph.D. in *entomology* from Cornell University. After listening to me *natter* for a while about my *lofty* goal of classifying all the ants of Alabama, he handed me a copy of Ernst Mayr's 1942 Systematics and the Origin of Species, Read it, he said, if you want to become a real biologist.

- epiphany: a sudden and surprising moment of understanding - entomology: the scientific study of insects - natter: an act of talking for a long time, especially about unimportant things - lofty: very high and impressive

Here is the argument. Outside our heads there is freestanding reality. Only madmen and a scattering of constructivist philosophers doubt its existence. Inside our heads is a reconstitution of reality based on sensory input and the self-assembly of concepts. Input and self-assembly, rather than an independent entity in the brain—the "ghost in the machine," in the philosopher Gilbert Ryle's famous derogation — constitute the mind. The alignment of outer existence with its inner representation has been distorted by the idiosyncrasies of human evolution, as I noted earlier. That is, natural selection built the brain to survive in the world and only incidentally to understand it at a depth greater than is needed to survive. The proper task of scientists is to diagnose and correct the misalignment. The effort to do so has only begun. No one should suppose that objective truth is impossible to attain, even when the most committed philosophers urge us to acknowledge that incapacity. In particular it is too early for scientists, the foot soldiers of *epistemology*, to yield ground so vital to their mission.

- epistemology: the part of philosophy that deals with knowledge (nhận thức luận)

The dream of objective truth peaked soon afterward with the formulation of logical positivism, a variation on general positivism that attempted to define the essence of scientific statements by means of logic and the analysis of language. Although many thinkers contributed to the movement, its driving force was the Vienna Circle, a group of mostly Austrian intellectuals founded by the philosopher Moritz Schlick in 1924. Regular meetings of the Circle continued until Schlick's death in 1936 and the subsequent dispersion of its members and correspondents, some of whom emigrated to America as *exiles* from the Nazi regime.

- exile: the state of being sent to live in another country that is not your own, especially for political reasons or as a punishment

BY ANY REASONABLE MEASURE OF achievement, the faith of the Enlightenment thinkers in science was justified. Today the greatest divide within humanity is not between races, or religions, or even, as widely believed, between the *literate and illiterate*. It is the chasm that separates *scientific from prescientific cultures*. Without the instruments and accumulated knowledge of the natural sciences—physics, chemistry, and biology—humans are trapped in a *cognitive prison*. They are like intelligent fish born in a deep, shadowed pool. Wondering and restless, longing to reach out, they think about the world outside. They invent ingenious speculations and myths about the origin of the confining waters, of the sun and the sky and the stars above, and the meaning of their own existence. But they are wrong, always wrong, because the world is too remote from ordinary experience to be merely imagined.

- faith: trust in somebody's ability or knowledge; trust that somebody/something will do what has been promised - illiterate: not knowing how to read or write - chasm: a very big difference between two people or groups, for example, because they have different attitudes

Original discovery is everything. *Scientists, as a rule, do not discover in order to know but rather, as the philosopher Alfred North Whitehead observed, they know in order to discover*. They learn what they need to know, often remaining poorly informed about the rest of the world, including most of the science for that matter, in order to move speedily to some part of the frontier of science where discoveries are made. There they spread out like *foragers* on a picket line, each alone or in small groups probing a carefully chosen, narrow sector. *When two scientists meet for the first time the usual conversation entry is, "What do you work on?"* They already know what generally bonds them. They are fellow prospectors pressing deeper into an abstracted world, content most of the time to pick up an occasional *nugget* but dreaming of the mother *lode*. They come to work each day thinking subconsciously, *It's there, I'm close, this could be the day.*

- forage: forage (for something) (especially of an animal) to search for food - nugget: a small lump of a valuable metal or mineral, especially gold, that is found in the earth; a small round piece of some types of food - lode: a line of ore (= metal in the ground or in rocks)

Yet the *grail eluded* them. Logical positivism *stumbled and halted*. Today its analyses, while favored by a few, are more commonly studied in philosophy, as dinosaur fossils are studied in *paleontology* laboratories, to understand the causes of extinction. Its last stand may have been a seldom-read 1956 monograph by Carnap in Minnesota Studies in the Philosophy of Science. The fatal flaw was in the semantic linch-pin of the whole system: The founders and their followers could not agree on the basic distinctions between fact and concept, between empirical generalization and mathematical truth, between theory and speculation, and from a collation of all these fog-shrouded *dichotomies*, the differences between scientific and non-scientific statements.

- grail: a thing that you try very hard to find or achieve, but never will - elude: elude somebody/something to manage to avoid or escape from somebody/something, especially in a clever way - stumble: an act of falling or almost falling, especially because you hit your foot against something - halt: to stop; to make somebody/something stop - paleontology: the study of fossils (= the remains of animals or plants in rocks) as a guide to the history of life on earth - dichotomies: dichotomy (between A and B) (formal) the separation that exists between two groups or things that are completely opposite to and different from each other

In one property of the electron, its magnetic moment, theory and experiment have been matched to the most extreme degree ever achieved in the physical sciences. The magnetic moment is a measure of the interaction between an electron and a magnetic field. More precisely, it is the maximum torque experienced by the electron divided by the magnetic induction acting on it. The quantity of interest is the *gyromagnetic* ratio, the magnetic moment divided in turn by the angular momentum. Theoretical physicists predicted the value of the gyromagnetic ratio with calculations incorporating both special relativity and perturbations from photon emission and resorption, the two phenomena expected from Q.E.D. to cause small deviations from the ratio previously predicted by classical atomic physics. For their part, and independently, atomic scientists directly measured the gyromagnetic ratio. In a technical tour de force, they trapped single electrons inside a magnetic-electric bottle and studied them for long periods of time. Their data matched the theoretical prediction to one part in a hundred billion. Together the theoretical and experimental physicists accomplished the equivalent of launching a needle due east from San Francisco and correctly calling in advance where it would strike (near Washington, D.C.) to within the width of a human hair.

- gyromagnetic ratio: In physics, the gyromagnetic ratio of a particle or system is the ratio of its magnetic moment to its angular momentum, and it is often denoted by the symbol γ, gamma. Its SI unit is the radian per second per tesla or, equivalently, the coulomb per kilogram. - geomagnetic: connected with or showing the magnetic (2) characteristics of the earth

Science, to put its warrant as concisely as possible, is the organized, systematic enterprise that gathers knowledge about the world and condenses the knowledge into testable laws and principles. The diagnostic features of science that distinguish it from pseudoscience are first, *repeatability*: The same phenomenon is sought again, preferably by independent investigation, and the interpretation given to it is confirmed or discarded by means of novel analysis and experimentation. Second, *economy*: Scientists attempt to abstract the information into the form that is both simplest and aesthetically most pleasing—the combination called elegance—while yielding the largest amount of information with the least amount of effort. Third, *mensuration*: If something can be properly measured, using universally accepted scales, generalizations about it are rendered unambiguous. Fourth, *heuristics*: The best science stimulates further discovery, often in unpredictable new directions; and the new knowledge provides an additional test of the original principles that led to its discovery. Fifth and finally, *consilience*: The explanations of different phenomena most likely to survive are those that can be connected and proved consistent with one another.

- heuristics: a method of solving problems by finding practical ways of dealing with them, learning from past experience

Theory: a word *hobbled* by multiple meanings. Taken alone without a or the, it *resonates* with *erudition*. Taken in everyday context, it is shot through with corrupting ambiguity. We often hear that such and such an assertion is only a theory. Anyone can have a theory; pay your money and take your choice among the theories that compete for your attention. Voodoo priests sacrificing chickens to please spirits of the dead are working with a theory. So are millenarian cultists watching the Idaho skies for signs of the Second Coming? Because scientific theories contain speculation, they too may seem just more guesswork, and therefore built on sand. That, I suspect, is the usual postmodernist conception: Everyone's theory has validity and is interesting. Scientific theories, however, are fundamentally different. They are constructed specifically to be blown apart if proved wrong, and if so destined, the sooner the better. "Make your mistakes quickly" is a rule in the practice of science. I grant that scientists often fall in love with their own constructions. I know; I have. They may spend a lifetime vainly trying to shore them up. A few *squander* their prestige and academic political capital in the effort. In that case—as the economist Paul Samuelson once quipped—funeral by funeral, theory advances.

- hobble: to walk with difficulty, especially because your feet or legs hurt - resonate: to make a deep, clear sound that continues for a long time - erudition: great academic knowledge - squander: to waste money, time, etc. in a stupid or careless way

My *intellectual* world was framed by Linnaeus, the eighteenth-century Swedish naturalist who invented modern biological classification. The Linnaean system is *deceptively* easy. You start by separating specimens of plants and animals into species. Then you sort species resembling one another into groups, the *genera*. Examples of such groups are all the crows and all the oaks. Next, you label each species with a two-part Latinized name, such as Corvus ossifragus for the fish crow, where Corvus stands for the genus—all the species of crows— and ossifragus for the fish crow in particular. Then on to higher classification, where similar genera are grouped into families, families into orders, and so on up to phyla and finally, at the very summit, the six kingdoms—plants, animals, fungi, protists, monerans, and archaea. It is like the army: men (plus women, nowadays) into squads, squads into platoons, platoons into companies, and in the final aggregate, the armed services headed by the joint chiefs of staff. It is, in other words, a conceptual world made for the mind of an eighteen-year-old.

- intellectual: connected with or using a person's ability to think in a logical way and understand things (trí óc, trí não) - deceptive: likely to make you believe something that is not true = misleading - genus --> genera (pl): a group into which animals, plants, etc. that have similar characteristics are divided, smaller than a family and larger than a species

To put that in a nutshell: knowledge, obsession, daring. The creative process is an opaque mix. Perhaps only openly confessional *memoirs*, still rare to nonexistent, might disclose how scientists actually find their way to a publishable conclusion. In one sense scientific articles are deliberately misleading. Just as a novel is better than the novelist, a scientific report is better than the scientist, having been stripped of all the confusions and ignoble thought that led to its composition. Yet such voluminous and incomprehensible *chaff*, soon to be forgotten, contains most of the secrets of scientific success.

- memoir: an account written by somebody, especially somebody famous, about their life and experiences - chaff: the outer covering of the seeds of grain such as wheat, which is separated from the grain before it is eaten

T H E D E S C E N T T O *minutissima*, the search for ultimate smallness in entities such as electrons, is a driving impulse of Western natural science. It is a kind of instinct. Human beings are obsessed with building blocks, forever pulling them apart and putting them back together again. The impulse goes as far back as 400 B.C. to the first proto-science, when Leucippus and his student Democritus speculated, correctly as it turned out, that matter is made of atoms. Reduction to microscopic units has been richly consummated in modern science.

- minutiae: very small details

In character, they are as variable as the population at large. Take any random sample of a thousand, and you will find the *near-full* human range on every axis of measurement—*generous to predatory, well adjusted to psychopathic, casual to driven, grave to *frivolous*, gregarious to reclusive*. Some are as *stolid* as tax accountants in April, while a few are clinically certifiable as *manic-depressives* (or bipolar, to use the ambiguous new term).

- near-full - frivolous: silly or amusing, especially when such behavior is not suitable - hào phóng với động vật ăn thịt, thích nghi tốt với tâm thần, tình cờ để lái xe, nghiêm trọng đến * phù phiếm *, * tham lam để ẩn dật - stolid: not showing much emotion or interest; remaining always the same and not reacting or changing - manic-depressive: bipolar

The laws of physics are in fact so accurate as to transcend cultural differences. They boil down to mathematical formulae that cannot be given Chinese or Ethiopian or Mayan *nuances*. Nor do they cut any slack for masculinist or feminist variations. We may even reasonably suppose that any advanced extraterrestrial civilizations, if they possess nuclear power and can launch spacecraft, have discovered the same laws, such that their physics could be translated *isomorphically*, point to point, set to point, and point to set, into human notation. The greatest exactitude of all has been obtained in measurements of the electron. A single electron is almost unimaginably small. Abstracted into a probabilistic packet of wave energy, it is also nearly impossible to visualize (as is the case generally for phenomena in quantum physics) within the conventional cognitive framework of objects moving in three-dimensional space. Yet we know with confidence that it has a negative charge of 0.16 billion-billionth (—1.6 X 10-19) coulomb and a rest mass of 0.91 billion-billion-billionth (9.1 X 10-28) gram. From these and other verifiable quantities have been accurately deduced the properties of electric currents, the electromagnetic spectrum, the photoelectric effect, and chemical bonding. The theory that unites such basic phenomena is an interlocking set of graphical representations and equations called *quantum electrodynamics* (Q.E.D.). Q.E.D. treats the position and momentum of each electron as both a wave function and a discrete particle in space. The electron is further envisioned in Q.E.D. as randomly emitting and reabsorbing photons, the unique massless particles that carry the electromagnetic force.

- nuance: a very slight difference in meaning, sound, colour or somebody's feelings that is not usually very obvious - isomorphically

Yet, *oddly*, there is very little science culture, at least in the strict tribal sense. Few *rites* are performed to speak of. There is at most only a scattering of icons. One does, however, hear a great deal of *bickering* over territory and status. The social organization of science most resembles a loose confederation of petty *fiefdoms*. In religious belief, individual scientists vary from born-again Christians, admittedly rare, to hard-core atheists, very common. Few are philosophers. Most are intellectual journeymen, exploring locally, hoping for a strike, living for the present. They are content to work at the discovery, often teaching science at the college level, pleased to be relatively well-paid members of one of the more contentious but overall least *conspiratorial* of professions.

- oddly: in a strange or unusual way - rite: a ceremony performed by a particular group of people, often for religious purposes - bickering: the activity of arguing about things that are not important - fief: an area of land, especially a rented area for which the payment is work, not money; an area or a situation in which somebody has control or influence - conspiratorial: connected with, or like, a conspiracy (âm mưu)

Is this *a paean* to the god of science? No—to human *ingenuity*, to the capacity in all of us, *freed* at last in the modern era. And to the fortunate comprehensibility of the universe. The signature achievement of humanity has been to find its way without assistance through a world that proved surprisingly well ordered.

- paean: a song of praise or victory - ingenuity: the ability to invent things or solve problems in clever new ways - free: to allow somebody to leave prison or somewhere they have been kept against their will

Science, even in the relatively tidy world of molecular genetics, is a *patchwork* of such arguments and proofs. But perhaps there are common elements in its methods. Can we devise a universal litmus test for scientific statements and with it eventually attain the grail of objective truth? Current opinion holds that we cannot and never will. Scientists and philosophers have largely abandoned the search for absolute objectivity and are content to *ply* their trade elsewhere. I think otherwise and will risk *heresy*: The answer could well be yes. Criteria of objective truth might be attainable through empirical investigation. The key lies in clarifying the still poorly understood operations composing the mind and in improving the piecemeal approach science has taken to its material properties.

- patchwork: a thing that is made up of many different pieces or parts - ply: to travel regularly along a particular route or between two particular places - heresy: a belief or an opinion that is against the principles of a particular religion; the fact of holding such beliefs

The Enchantment, growing steadily more sophisticated, has dominated scientific thought ever since. In modern physics its focus has been the unification of all the forces of nature—electroweak, strong, and gravitation—the hoped-for consolidation of theory so tight as to turn the science into a "perfect" system of thought, which by *sheer* weight of evidence and logic is made resistant to revision. But the spell of the Enchantment extends to other fields of science as well, and in the minds of a few, it reaches beyond into the social sciences, and still further, as I will explain later, to touch the humanities. The idea of the unity of science is not *idle*. It has been tested in acid baths of experiment and logic and enjoyed repeated *vindication*. It has suffered no decisive defeats. At least not yet, even though at its center, by the very nature of the scientific method, it must be thought always vulnerable. On this weakness, I will also expand in due course.

- physics: the scientific study of matter and energy and the relationships between them, including the study of forces, heat, light, sound, electricity and the structure of atoms - sheer: used to emphasize the size, degree or amount of something; complete and not mixed with anything else - to spell: to form words correctly from individual letters - idle: not working hard, not in use, with no particular purpose or effect; useless - vindication: proof that something is true or that you were right, especially when other people had a different opinion

Still, scientific theories are a product of imagination—informed imagination. They reach beyond their grasp to predict the existence of previously unsuspected phenomena. They generate hypotheses, disciplined guesses about unexplored topics whose parameters the theories help to define. The best theories generate the most fruitful hypotheses, which translate cleanly into questions that can be answered by observation and experiment. Theories and their *progeny* hypotheses compete for the available data, which comprise the limiting resource in the ecology of scientific knowledge. The survivors in this *tumultuous* environment are the Darwinian victors, welcomed into the canon, settling in our minds, guiding us to further exploration of physical reality, more surprises. And yes, more poetry.

- progeny: a person's children; the young of animals and plants - tumultuous: very loud; involving strong feelings, especially feelings of approval

Still, I had no desire to *purge* religious feelings. They were bred in me; they suffused the wellsprings of my creative life. I also retained a small measure of common sense. To wit, people must belong to a *tribe*; they yearn to have a purpose larger than themselves. We are obliged by the deepest drives of the human spirit to make ourselves more than animated dust, and we must have a story to tell about where we came from, and why we are here. Could Holy Writ be just the first literate attempt to explain the universe and make ourselves significant within it? Perhaps science is a continuation on new and better-tested ground to attain the same end. If so, then in that sense, science is religion liberated and *writ* large.

- purge: to remove people from an organization, often violently, because their opinions or activities are unacceptable to the people in power - tribe: a group of people of the same race, and with the same customs, language, religion, etc., living in a particular area and often led by a chief - writ: a legal document from a court telling somebody to do or not to do something

THE CUTTING EDGE of science is *reductionism*, the breaking apart of nature into its natural constituents. The very word, it is true, has a sterile and invasive ring, like scalpel or catheter. Critics of science sometimes portray reductionism as an obsessional disorder, declining toward a terminal stage one writer recently dubbed "reductive megalomania." That characterization is an actionable misdiagnosis. Practicing scientists, whose business is to make verifiable discoveries, to view reductionism in an entirely different way: It is the search strategy employed to find points of entry into otherwise impenetrably complex systems. Complexity is what interests scientists in the end, not simplicity. Reductionism is the way to understand it. *The love of complexity without reductionism makes art; the love of complexity with reductionism makes science*.

- reductionism: the belief that complicated things can be explained by considering them as a combination of simple parts

As the nineteenth century closed, the dream of objective truth was *rekindled* by two philosophies. The first, European in origin, was positivism, the conviction that the only certain knowledge is the exact description of what we perceive with our senses. The second, American in origin, was pragmatism, the belief that truth is what consistently works in human action. From the outset both positions were *symbiotic* with science. They drew major strength from the spectacular advances in the physical sciences then underway, which vindicated them by the varied actions—electromagnetic motors, X-rays, reagent chemistry— that exact, practical knowledge made possible.

- rekindle: to make something become active again - symbiotic: used to describe a relationship between two different living creatures that live close together and depend on each other in particular ways, each getting particular benefits from the other

We have even uncovered basic senses entirely outside the human *repertory*. Where humans detect electricity only indirectly by a tingling of skin or flash of light, the electric fishes of Africa and South America, a medley of freshwater eels, catfish, and elephant-nosed fishes, live in a galvanic world. They generate charged fields around their bodies with trunk muscle tissue that has been modified by evolution into organic batteries. The power is controlled by a neural switch. Each time the switch turns on the field, individual fish sense the resulting power with electroreceptors distributed over their bodies. *Perturbations* caused by nearby objects, which cast electric shadows over the receptors, allow them to judge size, shape, and movement. Thus continuously informed, the fish glide smoothly past obstacles in dark water, escape from enemies, and target prey. They also communicate with one another by means of *coded electrical bursts*. Zoologists, using generators and detectors, can join the conversation. They are able to talk as though a fish's skin.

- repertory: the type of work of a theatre company in which different plays are performed for short periods of time

Fail to discover, and you are little or nothing in the culture of science, no matter how much you learn and write about science. Scholars in the humanities also make discoveries, of course, but their most original and valuable scholarship is usually the interpretation and explanation of already existing knowledge. When a scientist begins to sort out knowledge in order to sift for meaning, and especially when he carries that knowledge outside the circle of discoverers, he is classified as a *scholar* in the humanities. Without scientific discoveries of his own, he may be a veritable *archangel* among intellectuals, his broad wings spread above science, and still not be in the circle. *The true and final test of a scientific career is how well the following declarative sentence can be completed: He (or she) discovered that...* A fundamental distinction thus exists in the natural sciences between process and product. The difference explains why so many accomplished scientists are narrow, foolish people, and why so many wise scholars in the field are considered weak scientists.

- scholar: a person who knows a lot about a particular subject because they have studied it in detail - archangel: an angel of the highest rank

On September 3-9, 1939, many of the scholars sympathetic to logical positivism met at Harvard University to attend the fifth International Congress for the Unity of Science. It was a *scintillating* assemblage of names now *enshrined* in the history of ideas: Rudolf Carnap, Phillip Frank, Susanne Langer, Richard von Mises, Ernest Nagel, Otto Neurath, Talcott Parsons, Willard van Quine, and George Sar- ton. The conferees must have been badly distracted by the invasion of Poland, which began two days before the meeting started. Where the Napoleonic campaigns weakened the plausibility of the original Enlightenment, now a savage war of territorial conquest fired by a pseudoscientific theory of racial superiority threatened to make a still greater mockery of the power of reason. The scholars persisted, however, in exploring the idea that rationally acquired knowledge is the best hope of humanity.

- scintillating: very clever, amusing and interesting

It is occasionally possible to encapsulate a method of science as a recipe. The most satisfying is that based on multiple competing hypotheses, also known as strong inference. It works only on relatively simple processes under restricted circumstances and particularly in physics and chemistry, where context and history are unlikely to affect the outcome. The phenomenon under *scrutiny* is known to occur but cannot be seen directly, with the result that its exact nature can only be guessed. Investigators think out every possible way the process might occur—the multiple competing hypotheses—and devise tests that will eliminate all but one.

- scrutiny: careful and thorough examination

Atomic-level imaging is the end product of three centuries of technological innovation in search of the final peek. Microscopy began with the primitive optical instruments of Anton van Leeuwenhoek, which in the late 1600s revealed bacteria and other objects a hundred times smaller than the resolution of the human eye. It has arrived at methods for showing objects a million times smaller. The passion for dissecting and reassembling has resulted in the invention of *nanotechnology*, the manufacture of devices composed of a relatively small number of molecules. Among the more impressive recent achievements are: - Etching stainless steel pins with ion beams, Bruce Lamartine and Roger Stutz of the Los Alamos National Laboratory have created high-density ROMs ("read-only memories"), whose lines are cut so fine, down to 150 billionths of a meter, as to allow the storage of two gigabytes of data on a pin 25 millimeters long and 1 millimeter wide. Since the materials are nonmagnetic, the information thus stored is nearly indestructible. Yet there is still a long way to go. In theory, at least, atoms can be ordered to store knowledge. - A fundamental question in chemistry since the work of Lavoisier in the eighteenth century has been the following: How long does it take a pair of molecules to meet and bond when different reagents are mixed together? By confining solutions to extremely small spaces, Mark Wightman and his fellow researchers at the University of North Carolina observed flashes of light that mark the contact of oppositely charged reagent molecules, enabling the chemists to time the reactions with unprecedented accuracy. - Molecule-sized machines that assemble themselves under the direction of technicians have for many years been considered a theoretical possibility. Now the ensembles are being realized in practice. One of the most promising techniques, engineered by George M. Whitesides of Harvard University and other organic chemists, consists in self-assembled monolayers. The SAMs (for short) consists of sausage-shaped molecules such as long hydrocarbon chains called alkanethiols. After synthesis in the laboratory the substances are painted onto a gold surface. One end of each molecule has properties that cause it to adhere to the gold; the other end, built of atoms with different properties, projects outward into space. Thus lined up like soldiers on parade, molecules of the same kind create a single layer only one to two nanometers thick. Molecules of a different construction are next laid down to create a second layer on top of the first, and so on, compound by compound, to produce a stratified film of desired thickness and chemical properties. SAMs share some of the basic properties of membranes of living cells. Their construction suggests one possible step in the eventual assembly of simple artificial organisms. Although far from being alive, SAMs are *simulacra* of elemental pieces of life. Given enough such components assembled the right way, chemists may someday produce a passable living cell.

- simulacrum: something that looks like somebody/something else or that is made to look like somebody/something else - passable: fairly good but not excellent

Quantum electrodynamics and evolution by natural selection are examples of successful big theories, addressing important phenomena. The entities they posit, such as photons, electrons, and genes, can be measured. Their statements are designed to be tested in the acid washes of *skepticism*, experiments, and the claims of rival theories. Without this vulnerability, they will not be accorded the status of scientific theories. The best theories are rendered lean by Occam's razor, first expressed in the 1320s by William of Occam. He said, "What can be done with fewer assumptions is done in vain with more." *Parsimony* is a criterion of a good theory. With lean, tested theory we no longer need Phoebus in a chariot to guide the sun across the sky, or *dryads* to populate the boreal forests. The practice grants less license for New Age dreaming, I admit, but it gets the world straight.

- skepticism: an attitude of doubting that claims or statements are true or that something will happen - vulnerability: the quality of being weak and easily hurt physically or emotionally - dryad: a female spirit who lives in a tree

I REMEMBER very well the time I was captured by the dream of unified learning. It was in the early fall of 1947, when at eighteen I came up from Mobile to Tuscaloosa to enter my *sophomore* year at the University of Alabama. A beginning biologist, fired by adolescent enthusiasm but short on theory and vision, I had schooled myself in natural history with field guides carried in a satchel during *solitary excursions* into the woodlands and along the freshwater streams of my native state. I saw science, by which I meant (and in my heart I still mean) the study of ants, frogs, and snakes, as a wonderful way to stay outdoors.

- sophomore: a student in the second year of a course of study at a college or university - sachet: a closed plastic or paper package that contains a very small amount of liquid or a powder - solitary: alone - excursion: a short journey made for pleasure, especially one that has been organized for a group of people

Evolutionary biology offers a simple answer. Natural selection, defined as the differential survival and reproduction of different genetic forms, prepares organisms only for necessities. Biological capacity evolves until it maximizes the fitness of organisms for the niches they fill, and not a *squiggle* more. Every species, every kind of butterfly, bat, fish, and primate, including Homo sapiens, occupies a distinctive niche. It follows that each species lives in its own sensory world. In shaping that world, natural selection is guided solely by the conditions of past history and by events occurring from moment to moment then and now. Because moths are too small and indigestible to be energetically efficient food for large primates, Homo sapiens never evolved *echolocation* to catch them. And since we do not live in dark water, an electrical sense was never an option for our species. Natural selection, in short, does not anticipate future needs. But this principle, while explaining so much so well, presents a difficulty. If the principle is universally true, how did natural selection prepare the mind for civilization before civilization existed? That is the great mystery of human evolution: how to account for calculus and Mozart. Later I will attempt an answer by expanding the evolutionary explanation to embrace the culture and technological innovation. For the moment, let me soften the problem somewhat by addressing the peculiar nature of the natural sciences as a product of history. Three preconditions, three strokes of luck in the evolutionary arena, led to the scientific revolution. The first was the boundless curiosity and creative drive of the best minds. The second was the inborn power to abstract the essential qualities of the universe. This ability was possessed by our Neolithic ancestors, but (again, here the primary puzzle) seemingly developed beyond their survival needs. In just three centuries, from 1600 to 1900, too short a time for improvement of the human brain by genetic evolution, humankind launched the techno-scientific age.

- squiggle: a line, for example in somebody's handwriting, that is drawn or written in a careless way with twists and curls in it - echolocation: the use of reflected sound waves for finding things, especially by creatures such as dolphins and bats

Differences in validation criteria across the disciplines are accordingly vast. Systematic biologists need only *stumble* upon an unusual new species, and recognize its novelty, to make an important discovery. In 1995, two Danish zoologists erected an entirely new phylum of animals, the thirty-fifth known, from a species of tiny rotifer like creatures found living on the mouthparts of lobsters. In a wholly different domain and style, biochemists regularly trace the natural syntheses of hormones and other biologically important molecules by duplicating the steps with enzymatically mediated reactions in the laboratory. Experimental physicists, even further removed than chemists from direct perception, and hence the most esoteric among the scientific multitude, deduce (to take a properly esoteric example) the spatial distribution of quarks from high-energy *collisions* of electrons with protons of atomic nuclei.

- stumble: an act of falling or almost falling, especially because you hit your foot against something - collision: an accident in which two vehicles or people crash into each other

On a far more modest scale, I found it a wonderful feeling not just to taste the unification metaphysics but also to be released from the confinement of fundamentalist religion. I had been raised a Southern Baptist, laid backward under the water on the *sturdy* arm of a pastor, been born again. I knew the healing power of *redemption*. Faith, hope, and charity were in my bones, and with millions of others I knew that my savior Jesus Christ would grant me eternal life. More *pious* than the average teenager, I read the Bible cover to cover, twice. But now at college, steroid-driven into moods of adolescent rebellion, I chose to doubt. I found it hard to accept that our deepest beliefs were set in stone by agricultural societies of the eastern Mediterranean more than two thousand years ago. I suffered cognitive dissonance between the cheerfully reported genocidal wars of these people and Christian civilization in 1940s Alabama. It seemed to me that the Book of Revela- tion might be black magic hallucinated by an ancient primitive. And I thought, surely a loving personal God, if He is paying attention, will not abandon those who reject the literal interpretation of the biblical cosmology. It is only fair to award points for intellectual courage. Bet- ter damned with Plato and Bacon, Shelley said, than go to heaven with Paley and Malthus. But most of all, Baptist theology made no provision for evolution. The biblical authors had missed the most important rev- elation of all! Could it be that they were not really privy to the thoughts of God? Might the pastors of my childhood, good and loving men though they were, be mistaken? It was all too much, and freedom was ever so sweet. I drifted away from the church, not definitively agnostic or atheistic, just Baptist no more.

- sturdy: strong and not easily damaged - redemption: the act of saving or state of being saved from the power of evil; the act of redeeming - pious: having or showing a deep respect for God and religion

Scientists have entered the visual world of animals and beyond because they understand the electromagnetic spectrum. They can translate any wavelength into visible light and audible sound, and generate most of the spectrum from diverse energy sources. By manipulating selected segments of the electromagnetic spectrum they peer downward to the trajectories of *subatomic* particles and outward to star birth in distant galaxies whose incoming light dates back to near the beginning of the universe. They (more accurately we, since scientific knowledge is universally available) can visualize matter across thirty-seven orders of magnitude. The largest galactic cluster is larger than the smallest known particle by a factor of the number one with about thirty-seven zeroes following it.

- subatomic: smaller than, or found in, an atom

FROM THESE AND countless other examples can be drawn an informal rule of biological evolution important to the understanding of the human condition: If an organic sensor can be imagined that picks up any signal from the environment, there exists a species somewhere that possesses it. The *bountiful* powers of life expressed in such diversity raise a question about the incapacity of the unaided human senses: Why can't our species, the supposed *summum bonum* of Creation, do as much as all the animals combined, and more? Why were we brought into the world physically handicapped?

- summum bonum: the highest good, especially as the ultimate goal according to which values and priorities are established in an ethical system.

The logical positivists who met in Cambridge knew that pure mathematics was on the road to the grail but not the prize itself. Mathematics, for all its unchallengeable power in framing theory, is *tautological*. That is, every conclusion follows completely from its own premises, which may or may not have anything to do with the real world. Mathematicians invent and prove lemmas and theorems that lead to other lemmas and theorems, and onward with no end in sight. Some fit data from the material world, some do not. The greatest mathematicians are intellectual athletes of dazzling skill. Sometimes they hit upon concepts that open new domains of abstract thought. Complex numbers, linear transformations, and harmonic functions are among those that have proved most interesting mathematically as well as useful to science.

- tautological: saying the same thing twice in different words, when this is unnecessary, for example 'They spoke in turn, one after the other.'

All our other senses have been expanded by science. Once we were deaf; now we can hear everything. The human auditory range is 20 to 20,000 Hz or cycles of air compression per second. Above that range, flying bats broadcast ultrasonic pulses into the night air and listen for echoes to locate moths and other insects on the wing. Many of their potential prey listen with ears tuned to the same frequencies as the bats. When they hear the *telltale* pulses, they dip and wheel in evasive maneuvers or else power-dive to the ground. Before the 1950s, zoologists were unaware of this nocturnal contest. Now, with receivers, transformers, and night-time photography they can follow every *squeak* and aerial *roll-out*.

- telltale: showing that something exists or has happened - squeak: to make a short high sound that is not very loud - roll-out: an occasion when a company introduces or starts to use a new product

Einstein, the architect of grand unification in physics, was Ionian to the core. That vision was perhaps his greatest strength. In an early letter to his friend Marcel Grossmann, he said, "It is a wonderful feeling to recognize the unity of a complex of phenomena that to direct observation appear to be quite separate things." He was referring to his successful alignment of the microscopic physics of capillaries with the macroscopic, universe-wide physics of gravity. In later life, he aimed to *weld* everything else into a single *parsimonious* system, space with time and motion, gravity with electromagnetism and cosmology. He approached but never captured that *grail*. All scientists, Einstein not excepted, are children of Tantalus, *frustrated by the failure to grasp that which seems within reach*. They are typified by those thermo-dynamicists who for decades have drawn ever closer to the temperature of absolute zero, when atoms cease all motion. In 1995, pushing down to within a few billionths of a degree above absolute zero, they created a Bose-Einstein condensate, a fundamental form of matter beyond the familiar gases, liquids, and solids, in which many atoms act as a single atom in one quantum state. As temperature drops and pressure is increased, a gas condenses into a liquid, then a solid; then appears the Bose-Einstein condensate. But absolute, entirely absolute zero, a temperature that exists in imagination, has still not been attained.

- to weld: to join pieces of metal together by heating their edges and pressing them together - parsimonious: extremely unwilling to spend money - grail: a thing that you try very hard to find or achieve, but never will

Behind the mere smashing of aggregates into smaller pieces lies a deeper agenda that also takes the name of reductionism: to fold the laws and principles of each level of organization into those at more general, hence more fundamental levels. Its strong form is total consilience, which holds that nature is organized by simple universal laws of physics to which all other laws and principles can eventually be reduced. This *transcendental* world view is the light and way for many scientific materialists (I admit to being among them), but it could be wrong. At the least, it is surely an *oversimplification*. At each level of organization, especially at the living cell and above, phenomena exist that require new laws and principles, which still cannot be predicted from those at more general levels. Perhaps some of them will remain forever beyond our grasp. Perhaps the prediction of the most complex systems from more general levels is impossible. That would not be all bad. I will confess with pleasure: The challenge and the crackling of thin ice are what gives science its metaphysical excitement.

- transcendental: going beyond the limits of human knowledge, experience or reason, especially in a religious or spiritual way

This level of creativity in science, as in art, depends as much on self-image as on talent. To be highly successful, the scientist must be confident enough to steer for blue water, abandoning sight of land for a while. He values risk for its own sake. He keeps in mind that the foot-notes of forgotten *treatises* are strewn with the names of the gifted but timid. If on the other hand, he chooses, like the vast majority of his colleagues, to hug the coast, he must be fortunate enough to possess what I like to define as optimum intelligence for normal science: bright enough to see what needs to be done but not so bright as to suffer *boredom* doing it.

- treatise: treatise (on something) (formal) a long and serious piece of writing on a particular subject - boredom: the state of feeling bored; the quality of being very boring

The thin volume in the plain blue cover was one of the New Synthesis works, uniting the nineteenth-century Darwinian theory of evolution and modern genetics. By giving a theoretical structure to natural history, it vastly expanded the Linnaean enterprise. A *tumbler* fell somewhere in my mind, and a door opened to a new world. I was *enthralled*, couldn't stop thinking about the implications evolution has for classification and for the rest of biology. And for philosophy. And for just about everything. Static pattern slid into fluid process. My thoughts, embryonically those of a modern biologist, traveled along a chain of causal events, from mutations that alter genes to evolution that multiplies species, to species that assemble into faunas and floras. Scale expanded, and turned continuous. By *inwardly* manipulating time and space, I found I could climb the steps in biological organization from microscopic particles in cells to the forests that clothe mountain slopes. A new enthusiasm *surged* through me. The animals and plants I loved so dearly reentered the stage as lead players in a grand drama. Natural history was validated as a real science.

- tumbler: a glass for drinking out of, with a flat bottom, straight sides and no handle or stem - enthralled: if something enthrals you, it is so interesting, beautiful, etc. that you give it all your attention - inwardly: in your mind; secretly - surge: to move quickly and with force in a particular direction

The search for the ultimate has been aided through direct visual observation by steady advances in the resolving power of microscopes. This technological enterprise satisfies a second elemental craving: to see all the world with our own eyes. The most powerful of modern instruments, invented during the 1980s, are the *scanning-tunneling microscope* and *atomic force microscope*, which provide an almost literal view of atoms bonded into molecules. A DNA double helix can now be viewed exactly as it is, including every twist and turn into which a particular molecule fell as the technician prepared it for study. Had such visual techniques existed fifty years ago, the infant science of molecular biology would have *escalated* even more sharply than it has. In science, as in whist and bridge, one peek is worth a hundred finesses.

- ultimate: happening at the end of a long process - escalate: to become or make something greater, worse, more serious, etc.

If those committed to the quest fail, they will be forgiven. When lost, they will find another way. The moral imperative of humanism is the endeavor alone, whether successful or not, provided the effort is honorable and failure memorable. The ancient Greeks expressed the idea in a myth of *vaulting* ambition. Daedalus escapes from Crete with his son Icarus on wings he has fashioned from feathers and wax. Ignoring the warnings of his father, Icarus flies toward the sun, *whereupon* his wings come apart and he falls into the sea. That is the end of Icarus in the myth. But we are left to wonder: Was he just a foolish boy? Did he pay the price for *hubris*, for pride in the sight of the gods? I like to think that, on the contrary, his daring represents a saving human grace. And so the great astrophysicist Subrahmanyan Chandrasekhar could pay tribute to the spirit of his mentor, Sir Arthur Eddington, by saying: *Let us see how high we can fly before the sun melts the wax in our wings.*

- vaulting: a pattern of arches in a ceiling or roof - whereupon: and then; as a result of this - hubris: the fact of somebody being too proud. In literature, a character with this pride ignores warnings and laws and this usually results in their downfall and death.

In motivation, they run from *venal to noble*. Einstein classified scientists very well during the celebration of Max Planck's sixtieth birthday in 1918. *In the temple of science, he said, are three kinds of people*. Many take to science out of a joyful sense of their superior intellectual power; for them, research is a kind of sport that satisfies personal ambition. A second class of researchers engages in science to achieve purely *utilitarian* ends. But of the third: If "the angel of the Lord were to come and drive all the people belonging to these two categories out of the temple, a few people would be left, including Planck, and that is why we love him."

- venal: prepared to do dishonest or immoral things in return for money - utilitarian: designed to be useful and practical rather than attractive

The scientist's style of investigation is the product of the discipline he chooses, further narrowed by aptitude and taste. If a naturalist at heart, he saunters at random, sometimes through real woods thick with trees, or, more commonly nowadays, cells thick with molecules, in search of objects and happenings still unimagined. His instinct is that of the hunter. If on the other hand, the scientist is a mathematical theorist, he creates a mental picture of a known but still poorly understood process, skeletonizes it into what intuition suggests are its essential elements, and recasts it in diagrams and equations. He looks for vindication, by saying to the experimentalists: If this is the way the process works, even if we cannot see it directly, then here are the parameters for an indirect probe and the language by which we might come to explain the results.

- vindication: proof that something is true or that you were right, especially when other people had a different opinion

No objective *yardstick* exists on which to mark these degrees of acceptance; there is nobody of external objective truth by which they can be calibrated. There is only warranted *assertability*, to use William James' phrase, within which particular descriptions of reality grow ever more congenial to scientists until objections cease. A proof, as the mathematician Mark Kac once put it, is that which convinces a reasonable man; a rigorous proof is that which convinces an unreasonable man.

- yardstick: a standard used for judging how good or successful something is - assertability: in a strong and confident way, so that people take notice of what you think or want

Persuasive

good at persuading someone to do or believe something through reasoning or the use of temptation.

Consilience

the unity of knowledge. Used to describe a scientific theory that has multiple lines of evidence to support it