THOUGHT OF A NONMILLENARIAN

     Maxine Singer
American Academy of Arts and Sciences
   Washington Meeting
     March 20,1997

As a scientist, I am not much inclined to think about the mystical or mythical

significance of dates. But some years ago, I awoke to the power of such ideas after
reading one of Vaclev Havel's stirring speeches (July 4, 1994, The Measure of Man), a

speech that received much attention. Havel joined his concerns about contemporary
society to the forthcoming end of the millenium in ways I found disturbing. He described
the approach to the millenium as a ``transitional period," a time when "all consistent value
systems collapse" when "everythmg is possible because our civilization does not have its
own spirit". And Havel held science responsible. You can understand my concern.

Besides tying the world's troubles to science, Havel's thoughts stirred me for

another reason. As a child, my religious school teachers had been at some pains to stress
that the year one, in the common calendar, was an adopted convention of no particular
significance. I was taught that for the years before 1, we counted backwards and labeled
them B.C.E.--Before the Common Era. We thus lived in the Common Era - whatever
that was. I was left to figure out for myself why in public school they used the same
numbers but different abbreviatio ns... B.C. and A.D. It took me some time to do that. To
make matters worse, I was taught another yearly numbering system, one that appears on
all Jewish calendars and on Rosh Hashonah notices &om my synagogue. It starts with
the beginning of the world, calculated back from the biblical generations, making the
current year 5757. Why do Havel, and others, then place such importance on a number
of no special consequence?

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Actually, by the time of Havel's speech I already knew that the year 2000 might

inspire some fuss. Foreseeing the destructive potential of millenarian thinking, A.
Bartlett Giamatti, then president of Yale had earlier warned us, in his typically eloquent
prose, to be wary.

" I believe that the new wisdom of a century's end is really only fatigue

masquerading as philosophy. I urge you to beware the captivation of these easy,
thoughtless profoundities. These banalities have only in common the belief that we are
not able to give definition--shape and contour--to what is around us. These shibboleths
finally tell more about those who utter them than about reality. They are expressions of
exhaustion more often than they are forms of explanation."

Giamatti here gives us a charge: to try to give definition --shape and contour-to

what is around us. And that is what I shall attempt, at least with respect to science and
technology. Far from being dead, or even suffering from exhaustion, science and
technology are spirited and robust. They compel us to inquire about our current and
foreseeable relations with the natural environment, which includes ourselves, other living
things, our planet, and the vast universe beyond. They also compel us to consider our
relations with the external environment we construct for ourselves through technology.

We will bring into the 2 1 st century knowledge about these environments that is

unprecedented in scope and depth. This has nothing to do with the new millenium. It is,
to large extent, the consequence of the far-reaching and enlightened support of
fimdamental scientific research by the U.S. government over the past 50 years. Our
knowledge is deep enough to give us considerable control over many aspects of nature,

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including our own lives and deaths. It is powerful enough to allow us to preserve or
destroy the very environment that supports us and gave us birth.

These are powers that we have sought. They can be used for good and misused

for evil. But they are not all-powerful. There remain strong, eternal forces within
ourselves and in the natural world that remain difficult or impossible to control.

Our vast, accumulated knowledge of the natural world will inform what we make

of the future. But though it is vast, it is also very incomplete; our ignorance is great.
Indeed, part of our knowledge is the recognition of things we don't know now, but can
anticipate adding to our store in the coming years; I will be talking about some of these
for most of my time. This class of unknowns was described by Woody Allen:

"There is no question that there is an unseen world. The problem is, how far is it

fiom midtown, and how late is it open?"

  But the future will also bring answers to some questions we haven't asked yet. A
fbture Woody Allen may even be driven to wonder if there are places besides Manhattan
We can glean an idea of the potential of what we don't know we don't know from some
concepts that were unimaginable at the start of the 20th century. The internal workings of
atoms were unknown; one clue, the existence of x-rays, was discovered just before the
new century began. No one knew that they didn't know about quantum physics or
relativity. Yet, from these discoveries came such a profound concept as the
interchangeability of matter and energy and thus nuclear energy and nuclear weapons as
well as semiconductor technology and the lasers that make so much of contemporary
technology possible. A hundred years ago, the word "computers" meant the women
employed to do calculations for astronomers. We didn't understand that our sun is only a

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modest star in a galaxy of billions of stars that is itself only one among billions of
galaxies in a universe that is not only beyond our ken in size but getting bigger all the

time.

We didn't know anything about viruses or antibiotics. Genes didn't have a name,

no less a chemical definition. The structure and significance of very large molecules, like
DNA and proteins, was as enigmatic as are black holes today. And the list goes on and


on.

The future will bring its own surprises because we know with a great deal of

certainty that there will be among us people of imagination, creativity, and skill who will
formulate the unasked questions and translate the new knowledge into new technologies.
The world that is coming will seem as strange to us as om would be to our great
grandparents. California, for them, was still a place for adventurers. Nowadays we all go
to California to see our kids. Will our grandchildren have to go to Mars to see theirs?

  Because of the things we don't know we don't know, the future is largely
unpredictable. But there are some things we can foresee because they are developments
anticipated or at least imaginable &om knowledge already in hand.

  Conmaon sense says that what we see is what there is. But in this instance
common sense and some philosophers are wrong. We can only see what our eyes
evolved to see. They are magnificent devices, but limited. Technology lets us see much
more. With TV we see in real time, things in far away places. With microscopes, we see
beautiful things too small for our eyes. As microscopes get smarter, smaller and smaller
things come into view. In the 219 century, we may well get a direct look at atoms.

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Telescopes allow us to see further and they too get better all the time, Space

telescopes like Hubble and enormous new telescopes on Earth see more and more distant
galaxies ....g alaxies so distant that their light took billions of years to reach us. We can
know those galaxies only as they once were, and they tell us about the early history of the
universe. With some microscopes and telescopes we see things that are invisible to us
because our eyes are insensitive to hfhred, ultraviolet, x-ray, and radio frequency

radiation. And then there is a lot of stuff out in the universe that we can't see at all

because it's dark. We know it is there only because of its gravitational effects. How

much dark matter is there? Some say it could represent as much as 90 percent of all the

matter there is. The answer to this question will determine whether the universe will

continue to expand or collapse back to a singularity of some sort or just hang-in there at

some size. When will we learn what that strange dark matter is? Is it some entirely new

kind of stuff? And if it is, will we find uses for it? Will it change our lives?

   Meanwhile, astronomers lives, like everyone else's, are being changed by

computer technology and hi-tech light collectors called charge-coupled devices (CCDs).
Though it is not as romantic as a kzing cold telescope dome on an isolated mountain,
astronomers in their warm ofices continents away can now control telescopes on the
planet or in space and collect the data with computers. Even high school students have
access to astronomical observations directly by computer and learn firsthand about

research.

Astronomers and other scientists were the first to come to depend on the internet.

Now, no one can imagine doing research or business without constant communication
with colleagues world-wide. And this is catalyzing an interesting cultural revolution: the
use of English as the world's common language. This could be an enormous fow for
unexpected developments. At least two countries are already frightened enou& to take

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steps to counter this revolution. France insists that home pages and information
originating from that country be in French, even when the source is an American
university outpost. Iranians have no access to the internet at all because of their

government's well-founded worries about the influences of American language and

culture.

Much closer to home than other galaxies or stars are the planets, moons, and

roaming objects of the solar system. The sun and about 4.5 billion years of history bind
us all together. In the future, people will forget a lot of the events we daily find so
compelling. But they will remember that in our time, for the first time, our species
visited Earth's moon, and sent surrogate visitors to other planets. What distant place will
be next for us? Will we go back to the moon? Will we walk on Mars? If so, we must
first learn to protect travelers fiom weightlessness, and from the intense radiation they
will encounter on the way. And such voyages will depend on our willingness to spend a
great deal of money. Right now we don't seem very bold or confident in our wealth....we

seem to have lost our nerve. Will that change?

   Our interest in Mars was revived a few months ago when a group of scientists
published surprising conclusions about a very ancient (4.5 Ga) piece of Mars that had
been lying around in Antarctica for 13,000 years; according to their interpretation of
their investigations, living things once inhabited Mars. A lot of scientists, including
myself, are skeptical. Earlier evidence fiom the Viking probe of Mars' surface seemed
definitively negative on this question, although the conclusion now seems less certain.
Chances are that we will want to settle the matter, fairly soon, with better and deeper
searches on the red planet and we'll want to have a look at the possibility of life on
Europa, a moon of Jupiter and other watering places in the Solar System. The quest will
Seem boring and uselessly expensive if the answer is NO, but it's hard to imagine

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anything more earth-shaking than discovering we have company in the universe even if it
is only microbes.

It's not surprising that a couple of random samples from Mars don't constitute a

satisfactory search when we are still discovering life of unanticipated kinds and in
unexpected places on Earth. In the last 25 years, a whole new class of organisms, the

archaebacteria, was discovered. To our astonishment, we've learned that bacteria live

deep within the rocks under Earth's surface apparently as deep as 200 meters. It's only in

the last 20 years that we have discovered strange organisms, and not only bacteria, but

worms and shrimp, living in what we thought would be inhospitable environments at the

deep sea hydrothermal vents where the margins of the great rocky tectonic plates spread

apart and material and heat spew out fiom deep within the Earth. Other unusual bacteria

live in the fluids bubbling out of the earth at the smelly hotspots like those that fascinate
us at Yellowstone. These bugs, and some at the submarine hydrothermal vents evolved
to live at temperatures we used to think impossible for life. Their chemistry is clearly
related to ours, as expected ifwe are distant cousins. But they don't wilt in the heat, like
we do. Their proteins and enzymes differ enough from ours to make them efficient even
at temperatures above the boiling point of water. Already, we have made use of some of
their enzymes; one of them is an essential tool in the methods used to determine the
DNA sequence of genomes, and to detect human mutations related to disease.

It is a great frustration that we can see out into the universe, but we can't see into

our own home planet. `Seeing' below the surface layers of the Earth now depends largely
on sophisticated analysis of seismic waves. Yet, we ought to know much more about the
shifting tectonic plates that lie under the Earth's surface, and the processes in the
underlying mantle and core if we are ever to be able to do a decent job of predicting

earthquakes or volcanic eruptions.

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Even without such fundamental knowledge it is now apparent that existing

seismological instruments can pick up phenomena that are characteristic precursors of
volcanic or earthquake activity, If sufficient numbers of instruments were deployed in
strategic places we might be able to predict at least some of these catastrophies at times

early enough to be useful.

   New insights into our planet are acquired from laboratory experiments under

conditions that simulate the deep earth. These studies are showing us that atoms we

thought we understood take on unusual properties at high temperatures and pressures.

Thus, fundamental studies in earth science are evolving into new chemistry and physics,

and who knows what new, amazing materials that can be used for innovative purposes.

   Our planet includes more than the solid earth on which we stand. The atmosphere

is part of the system as we are well aware when severe storms and serious flooding occur.

Like earthquakes and volcanic eruptions we have no control over these natural events.
But it would be enormously helpll if they could be predicted well ahead of onset.
Methods for short-term, reliable predictions are neither available or likely in near future.
But we're beginning to see the possibility of better understanding of weather on time
scales as long as decades. Few problems are more complex, or more hampered by a lack
of adequate technology or investment. Relevant factors include oceans and their surface
temperatures and circulation, global atmospheric circulation, and populations of
organisms, most particularly green plants and ourselves.

The connection between green plants and atmospheric conditions - that is, the

extent to which the composition and circulation of the atmosphere depend on exchanges
of C02, 02, and water by plants - reminds us of the intimate relations between the

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physical earth and the biosphere. Increasingly we recognize that we need to know much
more about each of these two worlds, and of their interactions, if we are to maintain the
planet as an hospitable environment for our own species.

  Among other things, we will have to decide how much more we want to know
about the uncounted number of species that share Earih with us. In the past we could,
without penalty, remain ignorant of most of them. No more!. It is now too easy for us to
destroy some organisms on which, unknown to us , we and our planet depend ... or might
in fhre find usell. The evolutionary history of our species ... our cultural as well as
biological evolution, has made us highly dependent organisms. We like to think that
because we're powerful, we're in charge. But we are not.

  For example, we evolved to breath oxygen, although oxygen was not an original
component of Earth's atmosphere. It was, and is, put there by algae and plants. We are
totally dependent on green plants for other essentials as well. Newly grown plants
provide clothing and shelter and food to supply the energy we need to run the machines
that are our bodies. The cooked remains of ancient plants give us energy sources in the
form of coal and oil to run the machines that we build. Up to the present, the only truly
eficient way to capture the energy of the sun has been through the intermediary of green
plants. In spite of a lot of effort, the technology we have for direct capture of the sun's
energy is only of limited utility--on satellites, but not on Earth. This could change in the
foreseeable future. We need to find alternative energy sources not only because what we
have is limited, but because the burning of fossil fuels degrades the environment of all

living things.

The United States should be proud of its Unique ~tional consensus on the

importance of the environment. But consensus and dedication will not be suffcient as

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the human population of the Earth increases and more and more of us become consumers.
Nor will cuircnt technologies that focus on conservation and recycling be enough. We
will need to adopt what we might call supply-side environmental strategies .... alternative

sources for energy and materials.

Fortunately, the genetic technology discovered and developed in the last quarter

of the 20th century is providing just such supply-side potential. The genetic engineering

of plants is a successful reality. Last summer, millions of U.S. acres were planted with

cotton, soybean and corn plants whose DNA contained genes derived from other

organisms. These genes protect against crop loss by predatory insects, and decrease

substantially the amount of chemical insecticide that farrners need to use. It is estimated

that humans will need, in the next 50 years, a quantity of v, heat and rice equal to all that

produced since our very ancient ancestors began the genetic experiments that gave us

doIne+.:+eCI cr i231 plants. Twenty-five yezus ago this would have seemed an impossible

challenge to the available resources of water and soil, but now genetically engineered

plants that grow on brackish water, are a realistic possibility. Experimental projects are
developing plants that can manufacture plastics that we now make from petroleum.
There is flx passibility that fuel oil might, in future, be harvested from engineered plants.
We are likely to be able to make vaccines, and some drugs in pl ants... a whole new breed
of herbal medicines. It is likely that we can engineer plants to salvage metals from
industrially contaminated sites. Even trees, whose life cycles normally consume many
years, can now be genetically altered because of the discovery of plant genes that speed
up the flomering cycle to a few months. Some people are imagining constructing trees

with increased cellulose content. This would decrease the number of trees and the

amount of noxious chemicals needed to supply our insatiable demand for paper.

In each of these instances, and others, genetically engineered plants will yield

unique, and cost-effective ways to harvest the sun's energy for human purposes.

Many people find these scenarios worrisome. Here in the U.S., we have tried to

deal with the realistic concerns about genetically engineered plants through careful

experiments and tests, through monitoring and regulation. This has allowed these new,
supply-side approaches to environmental issues to proceed safely. In contrast, in Europe,
fields of genetically engineered plants are frequently destroyed by people who are also

fervently dedicated to improving the environment. They have vehemently opposed the

importation of genetically engineered plants and plant-products like corn and soybean

from the U.S. In less than a year, the Swiss, for example, will vote on a proposal to ban

virtually all genetically engineered plants and animals. h4any of our European friends

and colleagues, and some people in our own country are sympathetic. They are unwilling

to rely on rigorous, governmental monitoring and control of the potential problems
associated with genetically engineered organisms. Moreover, many of the naysayers are

disturbed, not so much by realistic and controllable potentid problems, but by a belief

that there is something unnatural about these genetic technologies. But in fact, organisms

have been exchanging genes in nature probably since living things first appeared on Earth

about 3.7 billion years ago. And human beings have been manipulating the genes of

other organisms at least since agriculture began in prehistory, albeit by less precise
methods. We all, including the naysayers, live lives that are completely dependent on
'unnatural' things. The history of our species is a history of adopting 'unnatural'
technologies if they are useful, and we want them, and they don't do too much harm----
and sometimes even if they do a lot of harm. Once, recently, when someone was being
very critical of all technology because of its potential for misuse, I asked her if she would
like to give up her cheap nylon panty hose. She didn't understand my question. She had
::.:ver thought about the fact that manufacturing the hosiery was a very high-tech procks.

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  The unease about genetic engineering of plants is of a piece with concerns about
the genetic engineering of animals and especially humans, as well as other reproductive
technologies. Here too, there are tough, substantive issues as well as ill-defined unease.
We heard a good deal of both of these a couple of weeks ago when the Scottish sheep
named Dolly hit the front pages.

One perplexing set of concerns is in the clash of some religious and philosophical

beliefs with scientific goals and practical, beneficial opportunities. For example, some
genetically engineered animals are essential research tools for the investigation of human
disease, while others can be used to produce valuable therapeutic agents. These are the
goals that motivated the scientists who produced Dolly. Yet a coalition of U.S religious
leaders has sought to impede these developments by proposing a ban on the patenting of
human genes, cells, and organs, and other genetically modified organisms. Surely they
will extend their campaign to include clones like Dolly, and are also likely to want to ban
such clones altogether. Their argument is that genes, cells, and organisms, are creations
of God and not inventions of man. But scientists who synthesize genes by chemical
techniques in their laboratories and recognize the near identity of human genes with those
of other species, cannot think of human DNA molecules as holy. Moreover, it is, in a
sense, genes (that is DNA) that build cells and organisms.

Reaping the benefits of the new technologies requires commercial sector

participation, and that commitment may not occur without the protection of financial
investments that patents provide. We shall have to find a way to resolve the conflict
between religious and scientific views about molecules and biological organisms. We
shall also need to resolve the conflict between religious precepts and the moral imperative
to do all we can to relieve hum suffering and improve the human condition. This

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conflict is of course not new. In the late 18th century, for example, a great debate
occurred in our emerging nation about the morality of innoculations to limit the
devastation of small pox. Some religious leaders argued that if God had not wanted
humans to suffer f'rom it, He would not have created small pox. George Washington
himself had to force a political decision to innoculate American troops when the disease
threatened more devastation than British guns. Such arguments still appeal to some
among us, as we have seen in some reactions to AIDS.

  There are other problems that need resolution if we are to make constructive use
of genetic research. Already we are able to identify genetic changes that are associated
with certain diseases or predispositions to particular diseases. Some of these, like cystic
fibrosis and hemophilia and certain cancers are inherited disorders. Other cancers are
related to changes that occur in an individual's DNA in the course of a lifetime but are not
inherited. Increasingly sophisticated screening techniques (that depend on an enzyme
from the Yellowstone thermophiles) permit identification of individuals carrying such
gene changes, even before disease is manifest. Such information will engender personal
and familial anxieties and societal stress that need sympathetic, informed counselling.
We will need to assure that individuals are protected against discrimination in
employment and in health and life insurance. This is particularly important now for at
least two reasons. First, although diagnostic genetic screens can be defhitive, we lack
sufficient understanding to translate that information into reliable prognoses for
individuals. Second, there are no effective therapies for most of these disorders.  Early
in the 2 1 st Century, when the project to determine the entire structure of the human
genome is completed, this problem will be even more acute because many more genes
and associated diseases will be identifiable. It is likely that none of us will turn out to be
perfect----assuming we knew what perfect means.

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  Beyond these difficult challenges, and perhaps most deeply and universally felt, is
concern that modem biological research and the institution of broad-based genetic testing
will spur a malevolent renewal of interest in eugenics. Surely, such consideration
troubles most of those who have written in recent weeks about Dolly's significance for
our species. Differences in the depth of concern about eugenics help us to understand
European attitudes toward genetic engineering. Europeans hold more immediate
memories of its dangers than do most Americans. We are more likely than they to forget
the evil role that eugenics and geneticists played in the Holocaust.

   In thinking about this issue we need to distinguish carefblly between two very

different ways of using genetic and reproductive techniques. The first is unrelated to

eugenics. It is therapeutic intervention in diseased individuals or fetuses ...an approach

which, if we can get it to work, appears to have broad acceptability. Gene therapy itself

has no effect on inheritance because it deals with body cells; in mammals like ourselves,

the cells that give rise to eggs and sperm-the germ cells-are sequestered very early in the

development of an embryo. The second, which is relevant to eugenics, has to do with

aItering genes in eggs or sperm, which are the vehicles for passing genes from one

generation to the next and it has to do with cloning of humans.

   In order to carry out germ cell manipulations, at least with the technology
currently in use for experimental animals like mice, or farm animals like pigs and sheep,
the germ cells must be removed from the body and handled under laboratory conditions
before returning to a mother. There are, in fact, scientific reasons for believing that
alteration of genes in human eggs and sperm, even were it to become a possible and
reproducible technique, could not achieve a reliably improved genome and would
therefore not be a very good tool for eugenics. New mutaliom are continually generated
in all our cells, body and germ cells alike. And subsequent sexual reproduction will again

14

generate unique mixtures of genes whose interactions are so complex that it is difficult
even to imagine making them predictable.

  Cloning of course by-passes sexual reproduction at least in one generation.
Dolly's genome is likely to be almost identical to the genome of the sheep udder cell that
donated its DNA. She should not harbor many new or unique combinations of genes -
although it's possible that she carries a few. This is because the DNA in the donor cell
may not be a perfect duplicate of the DNA that initiated the development ofhlly's

biological mother. Body cells like udder cells are many cell generations removed from

the fertilized egg cell. At each cell generation some number of mutations collect at

random in the genome. Some of these could be lethal during development and this may

explain, in part, why only one Dolly was produced from 277 tries. Other such mutations

0

may cause her problems later in life - premature aging, infertility, or cancer are examples.

We shall want to follow her progress carefully. We will also want to know whether the
Dolly experiment is reproducible. This knowledge is an essential basis for any

discussion of human cloning.

  Moreover, what works for sheep may or may not work for humans. Any
experiment designed to find out if an adult human can be cloned requires making such a
clone and being prepared for a bad outcome. Do we, as a society, or any individuals

among us, want to do that experiment?

  Many scientists agree that in the absence of any indisputable therapeutic utility,
and without absolute assurance of complete safety, attempts to modify human eggs and
sperm by genetic engineering should not even be considered. At present, such assurances
are impossible. I believe that a similar consensus is likely to emerge with respect to
cloning humans. Thus, it is unliiely that any resurgent interest in eugenics will come

1s

from the scientific community. As far as I know, there is then no reason to infer evil
intent by scientists. There is, however, every reason to be wary and to discuss these
questions widely. As the science progresses, the broad community must carefully decide
what uses are important, desirable, and acceptable. The need for a well-informed
citizenry to cany out this discussion is one reason to encourage widespread improvement

in science education in America.

During this talk I have repeatedly said "we how this" or "we know that" about

the world around us. But of course, no one knows all these things, or the many other

promising scientific and technical deveIopments I have not mentioned. Even scientists

know very little about research outside their own fields. Biologists don't know much

about galaxies and astronomers little about genes. But as scientific knowledge gets

converted into usefkl technology, all of us must participate in the debates about the
relative potentials each technology has for good and for harm. Not everyone will have

the bent or want to be a scientist. But our definition of an educated person must now
include a sound appreciation of science and technology so that they can be wisely and
equitably used. Otherwise we risk unwise political decisions, decisions that are
incompatible with the natural world or a healthy environment, or political decisions that
deny us useful technologies on spurious, indefensible grounds. This will be an interesting
debate. Cautious, thoughtful people will want to move slowly. Luddites will not want to
move at all. Many people will be eager for any new technology if they think it can cure
loved ones, or improve capabilities deemed desirable, or make a buck. We need only
think about the illicit use of human growth hormone to grow tall and brawny athletes,
once it became cheap and available through recombinant DNA technology. And there are
bound to be a few people with sufficiently large egos and little understanding of the great
benefits of the genetic crap game to want to clone themselves.

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Already now, and increasingly in the future, the greatness of nations will be

measured by the knowledge and technology they produce and the wisdom with which
they put them to use. This measure will apply to national economies, to military power,

to intellectual influence and even to the arts which more and more mine science and

technology for creative projects and certainly for distribution. Our country has led the
world in increasing knowledge and technology and we have the best shot around for
maintaining that leadership. The proof is in the constant flow of newcurners who
emigrate here and enrich our society, because they know that this is the place to do
science, to develop technology. The United States is the leader not because we are
smarter than other nations, or because we are richer, but because we are a freer people.
Freedom breeds the optimism that is the most fertile ground for science and for

innovation.

In 1994, Vaclev Have1 tied his forebodings about the new millennium to what he

saw as the responsibility of science for the disappearance of God from the world--and
with Him, the source of the set of values embodied in the American Constitution and Bill
of Rights. But such pessimism conflicts profoundly with that very Same set of values.
Science, on the other hand, affirms the optimism of American values. We should accept
Giamatti's challenge and work "to give definition--shape and contour--to what is around
us." Our understanding of the natural world must be an integral part of that definition, as
I have tried to show. And that understanding clearly tells us that the history and future of
the universe and of our planet have nothing to do with the convenient ways in which we
enumerate the trips that Earth makes around the sun.

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