散文: Debating the unknowable

Do animals think? How could the earth show so many signs of design and purpose and yet be random? Our best scientists are heatedly debating both sides of these and other scientific questions. In the following essay, the author takes a look at science education and argues that as well ass telling students the facts and theories that have already been proved and accepted, science teacher should spend more time introducing their students to the many mysteries that remain unsolved and the arguments taking place between scientists. What better way, he argues, to stimulate their interest in thing scientific?

DEBATING THE UNKNOWABLE

Lewis Thomas

The greatest of all the accomplishment of twentieth-century science has been the discovery of human ignorance. We live, as never before, in puzzlement about nature, the universe, and ourselves most of all. It is a new experience for the species. A century ago, after the turbulence caused by Darwin and Wallace had subsided and the central idea of natural selection had been grasped and accepted, we thought we knew everything essential about evolution. In the eighteenth century there were no huge puzzles; human reason was all you needed in order to figure out the universe. And for most of the earlier centuries, the Church provided both the questions and the answers, neatly packaged. Now, for the first time in human history, we are catching glimpses of our incomprehension. We can still make up stories to explain the world, as we always have, but now the stories have to be confirmed and reconfirmed by experiment. This is the scientific method, and once started on this line we cannot turn back. We are obliged to grow up in skepticism, requiring proofs for every assertion about nature, and there is no way out except to move ahead and plug away, hoping for comprehension in the future but living in a condition of intellectual instability for the long time.

It is the admission of ignorance that leads to progress, not so much because the solving of a particular puzzle leads directly to a new piece of understanding but because the puzzle -- if it interests enough scientists -- leads to work. There is a similar phenomenon in entomology know as stigmergy, a term invented by Grasse, which means "to incite to work." When three or four termites are collected together in a chamber they wander about aimlessly, but when more termites are added, they begin to build. It is the presence of other termites, in sufficient numbers at close quarters, that produces the work: they pick up each other's fecal pellets and stack them in neat columns, and when the columns are precisely the right height, the termites reach across and turn the perfect arches that form the foundation of the termitarium. No single termite knows how to do any of this, but as soon as there are enough termites gathered together they become flawless architects, sensing their distances from each other although blind, building an immensely complicated structure with its own air-conditioning and humidity control. They work their lives away in this ecosystem built by themselves. The nearest thing to a termitarium that I can think of in human behavior is the making of language, which we do by keeping at each other all our lives, generation after generation, changing the structure by some sort of instinct.

Very little is understood about this kind of collective behavior. It is out of fashion these days to talk of "superorganisms", but there simply aren't enough reductionist details in hand to explain away the phenomenon of termites and other social insects: some very good guesses can be made about their chemical signaling systems, but the plain fact that they exhibit something like a collective intelligence is a mystery, or anyway an unsolved problem, that might contain important implications for social life in general. This mystery is the best introduction I can think of to biological science in college. It should be taught for its strangeness, and for the ambiguity of its meaning. It should be taught to premedical students, who need lessons early n their careers about the uncertainties in science.

College students, and for that matter high school students, should be exposed very early, perhaps at the outset, to the big arguments currently going on among scientists. Big arguments stimulate their interest, and with luck engage their absorbed attention. Few things in life are as engrossing as a good fight between highly trained and skilled adversaries. But the young students are told very little about the major disagreements of the day; they may be taught something about the arguments between Darwinians and their opponents a century ago, but they do not realize that similar disputes about other matters, many of them touching profound issues for our understanding of nature, are still going on and, indeed, are an essential feature of the scientific process. There is, I fear, a reluctance on the part of science teachers to talk about such things, based on the belief that before students can appreciate what the arguments are about they must learn and master the "fundamentals". I would be willing to see some experiments along this line, and I have in mind several examples of contemporary doctrinal dispute in which the drift of the argument can be readily perceived without deep or elaborate knowledge of the subject.

There is, for one, the problem of animal awareness. One school of ethologists devoted to the study of animal behavior has it that human beings are unique in the possession of consciousness, differing from al other creatures in being able to think things over, capitalize on past experience, and hazard informed guesses at the future. Other, "lower", animals (with possible exceptions made for chimpanzees, whales, and dolphins) cannot do such things with their minds; they live from moment to moment with brains that are programmed to respond, automatically or by conditioning, to contingencies in the environment, Behavioral psychologists believe that this automatic or conditioned response accounts for human mental activity as well, although they dislike that word "mental". On the other side are some ethologists who seems to be more generous-minded, who see no compelling reasons to doubt that animals in general are quite capable of real thinking and do quite a lot of it —— thinking that isn't as dense as human thinking, that is sparser because of the lack of language and the resultant lack of metaphors to help the thought along, but thinking nonetheless.

The point about this argument is not that one side or the other is in possession of a more powerful array of convincing facts; quite the opposite. There are not enough facts to sustain a genuine debate of any length; the question of animal awareness is an unsettled one.

Another debatable question arises when one contemplates the whole biosphere, the conjoined life of the earth. How could it have turned out to possess such stability and coherence, resembling as it does a sort of enormous developing embryo, with nothing but chance events to determine its emergence? Lovelock and Margulis, facing this problem, have proposed the Gaia Hypothesis, which is, in brief, that the earth is itself a form of life, "a complex entity involving the Earth's biosphere, atmosphere, oceans and soil; the totality constituting a feedback or cybernetic system which seeks an optimal physical and chemical environment for life on this planet." Lovelock postulates, in addition, that "the physical and chemical condition of the surface of the Earth, of the atmosphere, and of the oceans has been an is actively made fit and comfortable by the presence of life itself."

This notion is beginning to stir up a few signs of storm, and if it catches on, as I think it will, we will soon find the biological community split into fuming factions, one side saying that the evolved biosphere displays evidences of design and purpose, the other decrying such heresy. I believe that students should learn as much as they can about the argument.

One more current battle involving the unknown is between sociobiologists and antisociobiologists, and it is a marvel for students to behold. To observe, in open-mouthed astonishment, one group of highly intelligent, beautifully trained, knowledgeable, and imaginative scientists maintaining that all behavior, animal and human, is governed exclusively by genes, and another group of equally talented scientists asserting that all behaviors is set and determined by the environment or by culture, is an educational experience that no college student should be allowed to miss. The essential lesson to be learned has nothing to do with the relative validity of the facts underlying the argument. It is the argument itself that is the education: we do not yet know enough to settle such questions.

New Words

debate

vt. argue about (sth.) with sb., discuss

n. a discussion about a subject on which people have different views

unknowable

a. beyond comprehension, esp. beyond human comprehension

puzzlement

n. bewilderment, perplexity

turbulence

n. agitation; great disturbance 骚动，纷乱

turbulent a.

subside

vi. sink to a lower or more normal level; become less

package

vt. wrap or seal in a container, wrappings, etc. to attract purchasers

glimpse

n. a quick view or look

incomprehension

n. lack of comprehension; inability to understand

reconfirm

vt. confirm anew

skepticism

n. a doubting state or habit of mind; doubt

assertion

n. a positive statement; firm declaration

assert

vt. state positively; declare firmly

instability

n. lack of firmness; being unstable

admission

n. (an) act of accepting the truth (of sth.)

entomology

n. the branch of zoology that deals with insects 昆虫学

incite

vt. cause or encourage sb. to a strong feeling or action; provoke

termite

n. an insect that looks somewhat like white ants and eats the wood of buildings and furniture 白蚁

fecal

a. having to do with feces (waste matter discharged from the intestines)粪便的，排泄物的

column

n. a long, thin, upright structure; pillar; post

arch

n. a curved structure capable of bearing the weight of the material above it 拱

termitarium

n. nest of termites

flawless

a. without a flaw; perfect

flaw

n. a fault or weakness that makes sth. imperfect 瑕疵

air-conditioning

n. the system that uses machines to control the temperature of the air in a room or building

humidity

n. moisture, esp. of the air 湿气;湿度

ecosystem

n. an ecological system which relates all the plants, animals and people in an area to their surroundings, considered as a whole 生态系(统)

fashion

n. the popular way of dressing or behaving at a certain time

superorganism

n. a group of organisms (as of social insects) that function as a social unit

reductionist

a. having to do with a procedure or theory that reduces complex data or phenomena to simple terms

reduction n.

insect

n. a small animal with six les, a body divided into three main parts, and often wings 昆虫

exhibit

vt. show demonstrate

mystery

n. sth. that is not known or understood

unsolved

a. not solved or explained

introduction

n. a written or spoken explanation at the beginning of a book or speech

ambiguity

n. the possibility of two or more meanings; vagueness 模棱两可;意义不明确

ambiguous

a. having more than one possible meaning, permitting more than one possible interpretation or explanation

premedical

a. preparing for the study of medicine

outset

n. the beginning

engross

vt. take up all of; absorb

engrossing

a. (not of a person) very interesting

adversary

n. a person or group to whom one is opposed; opponent or enemy

adverse

a. hostile; unfavorable

Darwinian

a. of Charles Darwin or his theory of evolution

dispute

n. a quarrel, disagreement

feature

n. an important part or quality

reluctance

n. unwillingness

reluctant a.

doctrinal

a. of or having to do with doctrine

doctrine

n. a principle or set of principles (esp. of a religious or political kind) that is taught 主义;教条，学说

readily

ad. without difficulty, easily; without delay, quickly

perceive

vt. become aware of by seeing, hearing, tasting, smelling or touching; get an understanding of

awareness

n. the quality or state of being aware

ethologist

n. a person who studies ethology (the individual and comparative study of animal behavior, including that of man) (个体)生态学家;行为学家

consciousness

n. the condition being aware and able to understand what is happening; awareness

creature

n. a living person or animal

capitalize

vi. (on) profit by; use to one's own advantage included

hazard

vt. venture; risk

exception

n. the fact of being left out; (a cause of) not being included

chimpanzee

n. a small African ape with dark hair黑猩猩

whale

n. a large sea animal that resembles fish but breathes air 鲸

dolphin

n. a sea animal that has a snout like a beak 海豚

contingency

n. a chance happening; uncertain event

automatic

a. done or produced by the body without thought or control

automatically ad.

dislike

vt. consider unpleasant; not like

generous

a. willing to give or share; unselfish 慷慨的

generous-minded a.

sparse

a. thin; thinly scattered

resultant

a. happening as an effect; resulting

metaphor

n. a figure of speech in which two things are compared without using "like" or "as"

nonetheless

ad. in spite of that; nevertheless

sustain

vt. maintain or keep (sth.) going; confirm

genuine

a. real or true; not false

unsettled

a. not yet settled

debatable

a. lending itself to formal debate; having strong points on both sides

biosphere

n. the part of the world in which life can exist 生命层;生物圈

conjoin

vt. cause to join together or unite

coherence

n. natural or reasonable connection; consistency 连贯;一致性

coherent a.

resemble

vt. be like or similar to

embryo

n. the young of any creature in its first state before birth, or before coming out of an egg 胚胎

emergence

n. the act or fact or emerging

entity

n. sth. That has a real and separate existence; being; existence 实体;存在

totality

n. the state of being whole; completeness

feedback

n. a process in which the factors that produce a result are themselves modified, corrected, strengthened, etc. by that result 反馈

cybernetic

a. of, relating to, or involving cybernetics (控制论)

optimal

a. most favorable; best

optimum

n., a.

postulate

vt. assume without proof as a basis of reasoning; take for granted

notion

n. an idea, belief or opinion in one's mind; concept

fume

vi. give off vapor, gas or smoke; show anger or irritation

faction

n. a group or party within a large group 派别

evolve

v. develop gradually by a long continuous process 演化

decry

vt. express strong disapproval; cry out against

heresy

n. a belief different from the accepted belief of a church, school, profession or other group 异教;异端

sociobiologist

n. one who studies the biological basis for animal and human social behavior

antisociobiologist n.

behold

vt. have in sight; see

astonishment

n. great surprise; amazement

astonish vt.

imaginative

a. having or showing a strong imagination

govern

vt. direct or manage; rule; control

Phrases & Expressions

move ahead

go forward

plug away

work persistently

at close quarters

very near or near together

out of fashion

not popular or approved of

explain away

give a satisfactory reason for; remove objection to by means of a convincing argument

at the outset

at the beginning

on the part of

of or by (sb.)

have it (that)

maintain, assert (that)

think over

think carefully about; consider; study

capitalize on

profit by; make full use of (sth.)

in possession of

having; owing

stir up

excite; stimulate; provoke

catch on

become popular or fashionable

Proper Names

Lewis Thomas 刘易斯.托马斯

Darwin 达尔文

Walace 华莱士

Grasse 格拉斯

Lovelock 洛夫洛克

Margulis 马古利斯

Gaia 盖亚