We sometimes hear people
speaking about “gaps” in our scientific knowledge. People often
speak as if there were merely a few cracks or gaps in our scientific
knowledge, and that in the not-too-distant future those gaps will be
filled in (perhaps rather like some construction worker filling in
a few cracks in a wall, or like a photo restorer filling in a few
cracks in an old photo).
Is it correct to speak in
such a way? No, it isn't. But the reason is not that our scientific
knowledge is perfect. The reason is that our scientific knowledge is
so fragmentary and so tiny that it is misleading to use the term gaps
or cracks to refer to what we don't know. What we should be saying is
that what we do know is tiny, and what we do not know is vast.
Consider the current state
of our knowledge. We know about the surface of our planet and a few
other planets. But we live in a vast universe of billions of
galaxies, many of which have billions of stars. So we know nothing
about 99.99999999999999% of the planets of the universe.
We also know basically
nothing about most of the matter and energy in the universe.
Scientists say that 96% of the matter and energy is dark matter and
dark energy, which we know basically nothing about. We also have no
idea what caused the origin of the universe billions of years ago.
There are many mysteries regarding how we got from the supposedly
infinite density of the Big Bang to the orderly state the universe is
in now.
Considering only ourselves and our planet, we know almost nothing about mysteries
such as the origin of life and how our brains work. There is much
evidence of some great psychic reality that we are almost completely
ignorant about. Unraveling how the mind works seems a thousand year
project that we have barely started.
Given such realities, is
it accurate to say that there are “gaps” or “cracks” in our
knowledge? No, because such a term implies that we have learned a
good fraction of what there is to know. If someone asked you how much
you know about quantum chromodynamics, it would be most misleading
for you to say that there are gaps in your knowledge of quantum
chromodynamics (as that would imply you know a large fraction of that
topic). You should instead say that you know nothing or virtually nothing
about such a topic.
Rather than speaking of
gaps in our scientific knowledge, it is more truthful to say that our
knowledge of nature is fragmentary, and that we have acquired only a
few pieces in the vast jigsaw puzzle of nature. In the great
million-year project of unlocking the universe's secrets, we are
fledglings and newbies.
Those who sell a story of
scientific triumphalism often speak as if scientists are
like college juniors or seniors with not terribly much left to master
in the curriculum. But instead they (and the rest of us) are all like
kids who have merely finished the first few weeks of kindergarten.
Imagine a little child who
makes a trip to the seashore. After he observes a few seagulls and
fills up a bucket with shells, pebbles, and starfish, he may
congratulate himself on his splendid progress in understanding
nature. But ahead of him lies the vast and mysterious ocean, the
mysteries of which he has barely begun to unravel. That little child
is like humanity, which has so far accumulated only a few scattered
fragments of nature's deep and mysterious truths, too vast in number
to be enumerated.
But it is easy to
over-estimate how much we know, as the following little story
illustrates.
On a distant planet there
was a king who was curious about biology, and who wanted to know all
about beings such as himself. So he told his chief scientist, “Find
out all about the biology of creatures such as you and me.”
The chief scientist was a
bright young person with lots of energy, so he trekked around the
planet, for 10 years, making an exhaustive study of body shapes, skin
color, hair color, and external differences in form. He then returned
to the king, and triumphantly reported that he had found out almost
everything there was to know about creatures such as himself and the
king.
“No, you have barely
skimmed the surface,” said the king. “For you forgot to
investigate what is inside creatures such as you and me.”
So the chief scientist
spent 20 years doing dissection of corpses, to learn about internal
anatomy. He then announced triumphantly to the king that he had
learned practically everything there was to know about creatures such
as himself and the king.
“No, you have barely
skimmed the surface,” said the king. “For you forgot to
investigate what is inside creatures such as you and me, on a
microscopic level.”
So the chief scientist
spent 30 years doing microscopic studies. He then announced
triumphantly to the king that he had learned practically everything
there was to know about creatures such as himself and the king.
But then the king asked
him to explain the origin of life, to explain the mystery of
development, to explain the mystery of where and how body plans are
stored, to explain the origin of astounding biological complexity, and to explain the mystery of consciousness. The chief
scientist could not explain these things in a satisfactory way. It
seemed that understanding life required some deeper level of
understanding that the chief scientist would never be able to reach
in his lifetime. It also seemed that there are many layers to the
riddle of life, and that understanding the next layer is always twice
as hard as understanding the previous layer. Sadly the king once
again told the scientist: “You have barely skimmed the surface.”
Our scientists are often like
this chief scientist, often tending to triumphantly declare
their mastery of a topic when they have barely skimmed the surface of
some subject with oceanic depths.