- KNOWLEDGE IS OUR DESTINY:
TERRESTRIAL AND EXTRATERRESTRIAL INTELLIGENCE
The silent hours steal on ...
King Richard III
The question of all questions for humanity, the problem which lies
behind all others and is more interesting than any of them is that
of the determination of man’s place in Nature and his relation to
the Cosmos. Whence our race came, what sorts of limits are set to
our power over Nature and to Nature’s power over us, to what goal we
are striving, are the problems which present themselves afresh, with
undiminished interest, to every human being born on earth.
T. H. HUXLEY,
AND so at last I return to one of the questions with which I
started: the search for extraterrestrial intelligence. While the
suggestion is sometimes made that the preferred channel of
interstellar discourse will be telepathic, this seems to me at best
a playful notion. At any rate, there is not the faintest evidence in
support of it; and I have yet to see even moderately convincing
evidence for telepathic transmission on this planet.
We are not yet
capable of significant interstellar space flight, although some
other more advanced civilization might be. Despite all the talk of
unidentified flying objects and ancient astronauts, there is no
serious evidence that we have been or are being visited.
That, then, leaves machines. Communication with extraterrestrial
intelligence may employ the electromagnetic spectrum, and most
likely the radio part of the spectrum; or it might employ gravity
waves, neutrinos, just conceivably tachyons (if they exist), or some
new aspect of physics that will not be discovered for another three
centuries. But whatever the channel, it will require machines to
use, and if our experience in radioastronomy is any guide,
computer-actuated machines with abilities approaching what we might
To run through many days’ worth of data on 1,008
different frequencies, where the information may vary every few
seconds or faster, cannot be done well by visually scanning the
records. It requires autocorrelation techniques and large electronic
computers. And this situation, which applies to observations that
Frank Drake of Cornell and I have recently performed at the Arecibo
Observatory, can only become more complex-that is, more dependent on
computers-with the listening devices likely to be employed in the
near future. We can design receiving and transmitting programs of
immense complexity. If we are lucky we will employ stratagems of
great cleverness and elegance. But we cannot avoid utilizing the
remarkable capabilities of machine intelligence if we wish to search
for extraterrestrial intelligence.
The number of advanced civilizations in the Milky Way Galaxy
today depends on many factors, ranging from the number of
planets per star to the likelihood of the origin of life. But once
life has started in a relatively benign environment and billions
of years of evolutionary time are available, the expectation of
many of us is that intelligent beings would develop. The
evolutionary path would, of course, be different from that taken on
The precise sequence of events that have taken place
here-including the extinction of the dinosaurs and the recession of
the Pliocene and Pleistocene forests-have probably not occurred in
precisely the same way anywhere else in the entire universe. But
there should be many functionally equivalent pathways to a similar
end result. The entire evolutionary record on our planet,
particularly the record contained in fossil endocasts, illustrates a
progressive tendency toward intelligence. There is nothing
mysterious about this: smart organisms by and large survive better
and leave more offspring than stupid ones.
The details will
certainly depend on circumstances, as, for example, if nonhuman
primates with language have been exterminated by humans, while
slightly less communicative apes were ignored by our ancestors. But
the general trend seems quite clear and should apply to the
evolution of intelligent life elsewhere. Once intelligent beings
achieve technology and the capacity for self-destruction of their
species, the selective advantage of intelligence becomes more
And what if we receive a message? Is there any reason to think that
the transmitting beings-evolved over billions of years of geological
time in an environment vastly different from our own-would be
sufficiently similar to us for their messages to be understood? I
think the answer must be yes. A civilization transmitting radio
messages must at least know about radio. The frequency, time
constant, and bandpass of the message are common to transmitting and
receiving civilizations. The situation may be a little like that of
amateur or ham radio operators. Except for occasional emergencies,
their conversations seem almost exclusively concerned with the
mechanics of their instruments: it is the one aspect of their lives
they are certain to have in common.
But I think the situation is far more hopeful than this. We know
that the laws of nature-or at least many of them-are the same
everywhere. We can detect by spectroscopy the same chemical
elements, the same common molecules on other planets, stars
and galaxies; and the fact that the spectra are the same shows
that the same mechanisms by which atoms and molecules are induced to
absorb and emit radiation exist everywhere.
Distant galaxies can be
observed moving ponderously about each other in precise accord with
the same laws of gravitation that determine the motion of a tiny
artificial satellite about our pale blue planet Earth. Gravity,
quantum mechanics, and the great bulk of physics and chemistry are
observed to be the same elsewhere as here.
Intelligent organisms evolving on another world may not be like us
biochemically. They will almost certainly have evolved significantly
different adaptations-from enzymes to organ systems-to deal with the
different circumstances of their several worlds. But they must still
come to grips with the same laws of nature.
The laws of falling bodies seem simple to us. At constant
acceleration, as provided by Earth’s gravity, the velocity of a
falling object increases proportional to the time; the distance
fallen proportional to the square of the time. These are very
elementary relations. Since Galileo at least, they have been fairly
generally grasped. Yet we can imagine a universe in which the laws
of nature are immensely more complex. But we do not live in such a
universe. Why not? I think it may be because all those organisms who
perceived their universe as very complex are dead.
Those of our
arboreal ancestors who had difficulty computing their trajectories
as they brachiated from tree to tree did not leave many offspring.
Natural selection has served as a kind of intellectual sieve,
producing brains and intelligences increasingly competent to deal
with the laws of nature. This resonance, extracted by natural
selection, between our brains and the universe may help explain a
quandary set by Einstein: The most incomprehensible property of the
universe, he said, is that it is so comprehensible.
If this is so, the same evolutionary winnowing must have occurred on
other worlds that have evolved intelligent beings.
Extraterrestrial intelligences that lack avian or arboreal
ancestors may not share our passion for space flight. But all
planetary atmospheres are relatively transparent in the visible
and radio parts of the spectrum-because of the quantum mechanics of
the cosmically most abundant atoms and molecules. Organisms
throughout the universe should therefore be sensitive to optical
and/or radio radiation, and, after the development of physics, the
idea of electromagnetic radiation for interstellar communication
should be a cosmic commonplace-a convergent idea evolving
independently on countless worlds throughout the galaxy after the
local discovery of elementary astronomy, what we might call the
facts of life.
If we are fortunate enough to make contact with some
of those other beings, I think we will find that much of their
biology, psychology, sociology and politics will seem to us
stunningly exotic and deeply mysterious. But I suspect we will have
little difficulty in understanding each other on the simpler aspects
of astronomy, physics, chemistry and perhaps mathematics.
I would certainly not expect their brains to be anatomically or
physiologically or perhaps even chemically close to ours. Their
brains will have had different evolutionary histories in different
environments. We have only to look at terrestrial beasts with
substantially different organ systems to see how much variation in
brain physiology is possible. There is, for example, an African
fresh-water fish, the Mormyrid, which often lives in murky water
where visual detection of predators, prey or mates is difficult.
The Mormyrid has developed a special organ which establishes an electric
field and monitors that field for any creatures traversing it. This
fish possesses a cerebellum that covers the entire back of its brain
in a thick layer reminiscent of the neocortex of mammals. The
Mormyrids have a spectacularly different sort of brain, and yet in
the most fundamental biological sense they are far more closely
related to us than any intelligent extraterrestrial beings.
The brains of extraterrestrials will probably have several or many
components slowly accreted by evolution, as ours have.
There may still be a tension among their components as among
ours, although the hallmark of a successful, long-lived
civilization may be the ability to achieve a lasting peace among
the several brain components. They almost certainly will have
significantly extended their intelligence extrasomatically, by
employing intelligent machines. But I think it highly probable that
our brains and machines and their brains and machines will
ultimately understand one another very well.
The practical benefits as well as the philosophical insights likely
to accrue from the receipt of a long message from an advanced
civilization are immense. But how great the benefits and how fast we
can assimilate them depend on the details of the message contents,
about which it is difficult to make reliable predictions. One
consequence, however, seems clear; the receipt of a message from an.
advanced civilization will show that there are advanced
civilizations, that there are methods of avoiding the
self-destruction that seems so real a danger of our present
Thus the receipt of an interstellar
message would provide a very practical benefit that in mathematics
is called the existence theorem-in this case the demonstration that
it is possible for societies to live and prosper with advanced
technology. Finding a solution to a problem is helped enormously by
the certain knowledge that a solution exists. This is one of many
curious connections between the existence, of intelligent life
elsewhere and the existence of intelligent life on Earth.
While more rather than less knowledge and intelligence seems so
clearly the only way out of our present difficulties and the only
aperture to a significant future for mankind (or indeed to any
future at all), this is not a view always adopted in practice.
Governments often lose sight of the difference between
short-term and long-term benefits. The most important
practical benefits have come about from the most unlikely and
apparently impractical scientific advances. Radio is today not
only the prime channel in the search for extraterrestrial
intelligence, it is the means by which emergencies are
responded to, news is transmitted, telephone calls relayed and
global entertainment aired. Yet radio came about because a
Scottish physicist, James Clerk Maxwell, invented a term, which
he called the displacement current, in a set of partial
differential equations now known as Maxwell’s equations. He
proposed the displacement current essentially because the
equations were aesthetically-more appealing with it than without it.
The universe is intricate and elegant. We wrest secrets from nature
by the most unlikely routes. Societies will, of course, wish to
exercise prudence in deciding which technologies-that is, which
applications of science-are to be pursued and which not. But without
funding basic research, without supporting the acquisition of
knowledge for its own sake, our options become dangerously limited.
Only one physicist in a thousand need stumble upon something like
the displacement current to make the support of all thousand a
superb investment for society. Without vigorous, farsighted and
continuing encouragement of fundamental scientific research, we are
in the position of eating our seed corn: we may fend off starvation
for one more winter, but we have removed the last hope of surviving
the following winter.
In a time in some respects similar to our own, St. Augustine of
Hippo, after a lusty and intellectually inventive young manhood,
withdrew from the world of sense and intellect and advised others to
“There is another form of temptation, even more fraught
with danger. This is the disease of curiosity. ... It is this which
drives us on to try to discover the secrets of nature, those secrets
which are beyond our understanding, which can avail us nothing and
which men should not wish to learn. ... In this immense forest, full
of pitfalls and perils, I have drawn myself back, and pulled myself
away from these thorns.
In the midst of all these things which float unceasingly around me
in everyday life, I am never surprised at any of them, and never
captivated by my genuine desire to study them. ... I no longer dream
of the stars.”
The time of Augustine’s death, 430 A.D., marks the
beginning of the Dark Ages in Europe.
In the last chapter of The Ascent of Man Bronowski confessed
himself saddened “to find myself suddenly surrounded in the
West by a sense of terrible loss of nerve, a retreat from
knowledge.” He was talking, I think, partly about the very
limited understanding and appreciation of science and
technology-which have shaped our lives and civilizations-in
public and political communities; but also about the increasing
popularity of various forms of marginal, folk- or pseudo-science,
mysticism and magic.
There is today in the West (but not in the East) a resurgent
interest in vague, anecdotal and often demonstrably erroneous
doctrines that, if true, would betoken at least a more interesting
universe, but that, if false, imply an intellectual carelessness, an
absence of tough-mindedness, and a diversion of energies not
very promising for our survival.
Such doctrines include:
astrology (the view that which stars, one hundred trillion miles
away, are rising at the moment of my birth in a closed building
affect my destiny profoundly)
the Bermuda Triangle “mystery”
(which holds in many versions that an unidentified flying object
lives in the ocean off Bermuda and eats ships and airplanes)
flying saucer accounts in general; the belief in ancient
the photography of ghosts
the view that my razor blade stays sharper within a cardboard
pyramid than within
a cardboard cube)
auras and Kirlian photography
the emotional lives and musical preferences of geraniums
flat and hollow earths
remote cutlery warping
Atlantis and Mu
the doctrine of
the special creation, by God or gods, of mankind despite our
deep relatedness, both in biochemistry and in brain physiology,
with the other animals
It may be that there are kernels of truth
in a few of these doctrines, but their widespread acceptance
betokens a lack of intellectual rigor, an absence of skepticism,
a need to replace experiments by desires. These are by and
large, if I may use the phrase, limbic and right-hemisphere
doctrines, dream protocols, natural-the word is certainly
perfectly appropriate-and human responses to the complexity
of the environment we inhabit.
But they are also mystical and
occult doctrines, devised in such a way that they are not
subject to disproof and characteristically impervious to rational
discussion. In contrast, the aperture to a bright future lies
almost certainly through the full functioning of the neocortex-reason alloyed with intuition and with limbic and R-complex
components, to be sure, but reason nonetheless: a courageous working
through of the world as it really is.
It is only in the last day of the Cosmic Calendar that substantial
intellectual abilities have evolved on the planet Earth. The
coordinated functioning of both cerebral hemispheres is the tool
Nature has provided for our survival. We are unlikely to survive if
we do not make full and creative use of our human intelligence.
“We are a scientific civilization,” declared
Jacob Bronowski. “That
means a civilization in which knowledge and its integrity are
crucial. Science is only a Latin word for knowledge...
Knowledge is our destiny."
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