There is an intellectual
sin that is very common among many modern scientists: the sin of
speaking as if they had explanations that account for long-standing
puzzles of nature, even if they don't really have such
explanations, but at best merely have small fragments of such
explanations. Imagine a person who doesn't have a blanket, but merely
has some threads picked up from various places on the floor. Such a
person might try to call those threads a blanket, or most of a
blanket, but that would be quite an exaggeration. Similar to such a
person, many a modern scientist speaks as if he is some great
knowledge lord who has mastered some deep puzzle of nature, when he
is merely someone familiar with a few things that might be fragments of the solution of such a puzzle (like individual pieces of
a 50-meter-long jigsaw puzzle).
I read an example of this
type of exaggeration today in a post by cosmologist Ethan Siegel.
Siegel makes this claim: “The inflationary Big Bang Universe, with
radiation, normal matter, dark matter and dark energy, explains the
full suite of absolutely everything we’ve ever observed, and
nothing else does.” Is this statement true? No, it's a ridiculous
case of overselling a very patchy theoretical framework.
First, the
inflationary Big Bang universe theory does not explain the origin of
the universe itself, leaving it as a complete mystery. Second, there are many important physical things unexplained by the inflationary Big Bang theory -- things such as the hierarchical structure of the universe, the CMB cold spot, the persistence of spiral galaxies, and the fine tuning of fundamental constants that makes possible a habitable universe. Third, we
have no real understanding of either dark energy or dark matter. Neither
is part of the Standard Model of Physics. The very terms “dark matter”
and “dark energy” are pretty much just euphemisms for “some kind
of mysterious something that we know nothing about.” So claiming
that explains something (or is part of an explanation) is erroneous.
When physicists and
cosmologists actually do calculations relevant to the issue of dark
energy, they get a shocking result: that the vacuum of space should
be filled with a dark energy or cosmological constant more than a
billion trillion quadrillion times (more than
1,000,000,000,000,000,000,000,000,000,000,000,000 times) larger than
we observe. This is the completely unsolved “cosmological constant”
problem (sometimes called the vacuum catastrophe) that has long
haunted physics and cosmology (it is discussed here). Claiming that dark energy is part
of some explanation of “absolutely everything we've ever observed”
is hilarious. Better to say that dark energy is part of the reason
we can't even explain the simplest thing we can think of (the
vacuum) – because according to physicist's calculations the vacuum
should be so packed with dark energy that it should have more
mass-energy than solid steel.
There are other fields of
inquiry in which scientists claim to understand puzzles of nature
they do not understand, by trying to exaggerate what they have
learned. One such field is the field of biology. Here the most
prominent cases of explanatory exaggeration involve
evolution and natural selection. We commonly hear scientists speak as
if evolution is some magic potion that explains
“in one fell swoop” how it is that there came to be beings such
as us on this planet.
But it isn't. While
evolution and natural selection are very probably important pieces in
the puzzle of the origin of intelligent life on our planet, they are
probably no more than pieces in that jigsaw puzzle. For one thing, neither
evolution nor natural selection can explain either the origin of life
or the origin of the genetic code. That's because both evolution and
natural selection require life itself, and you can't explain the origin of life by
something that requires life.
Moreover, humans have
many special mental and spiritual capabilities that are extremely
difficult or impossible to explain by natural selection or evolution.
Humans have inner selves and personalities. Humans are great at
language, and at formulating very abstract ideas. Humans are capable
of wonder, joy, love, guilt, compassion, imagination, and
spirituality. Humans can create art and literature, ponder their own
deaths, wonder about the meaning of life and the nature of the
universe, create and follow moral codes, and consider philosophical
matters. As argued here, it is hard to explain most of these things by evoking evolution or
natural selection, because most of them have no survival value, from an
evolutionary standpoint of making an organism more likely to survive
until it reproduces.
Things evolution has a hard time explaining
How did humanity get these
things? We don't know. The modern biologist offers an unconvincing,
simplistic explanation – “it all just came from evolution.” But
the actual explanation is probably far deeper and more complex. I can
understand why the biologist would wish to offer this answer of “it all just came from evolution.” It is always better to be able
to say, “I have the answer to this great mystery of nature,” than
to say, “I have but a few tiny fragments that may one day be of use
in solving this great puzzle.” It is always more pleasing to put
yourself on a pedestal marked “Great Lord of Knowledge” than to
humbly realize that the puzzles of nature vastly exceed your meager
understanding.
If you point out the explanatory limits of evolution to a biologist, you may be attacked as an evolution denier, even if you did not at all deny it, but merely pointed out its explanatory limits.
Another example of
inflated knowledge pretensions involve claims about the human brain.
Scientists have done some brain imaging studies showing how parts of
the brain light up differently under different conditions. If you
read some enthusiastic reports of such studies, you might get the
idea that scientists have a deep understanding of how our brains
work. But they don't.
As the book Mind and
Brain: A Critical Appraisal of Cognitive Neuroscience makes
clear, brain imaging studies have cast relatively little light on the
mysterious workings of the brain. Here are some points made on page
365-366 of the book:
Brain imaging
meta-studies show that when the results of a number of experiments
are pooled, the typical result is to show activations over most of
the brain, rather than convergence on a single location...
Considerable portions of modern cognitive neuroscience's empirical
research support the idea that every cognitive process is a product
of the action of a highly integrated system in which many parts of
the brain interact rather than function independently as isolated
regions...There has been little replication of most findings...No
part of the brain has only a single, unique function...Clinical data,
especially with traumatic injuries, do not display high degrees of
correlation between particular brain lesions and cognitive states.
It
would seem that those who claim to understand the brain through some
kind of “this part does this thing” approach are exaggerating
their understanding, and that the brain is still a deep, intractable
mystery. Indeed, there is every reason to suspect that we are
centuries away from being able to understand the brain's secrets.
How is it that these
examples of knowledge hubris become so widely accepted? How is it
that again and again our scientists get people to think that they are
knocking on a door marked “Final Explanation” when they have
often just walked a few paces down the long, long road that leads to
that door? Part of the reason is that it's like a school where there
are no teachers to give scientists grades, and they can make their
own grades. Imagine if you were at a school without any teachers,
one in which you give yourself a grade. You might learn just a few
facts about modern history (such as the fact that soldiers landed on
a beach on June 6, 1944, and the fact that some bombs were dropped on
December 7, 1941). You might then conclude that because you had
learned these things, you now had a deep understanding of modern
history, and give yourself an “A” in the Modern History course.
There would be no one around to say, “no, no, you have learned just
the tiniest fraction of what you need to know to understand that
topic.” Similarly, there is no one around to correct the scientist
who fancies himself a knowledge lord after learning but a few paltry
fragments of nature's vast and deep secrets.
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