(credit: Edmonton Public Schools)
In
grade 9, I had a really good Science teacher. He loved Science, he loved kids,
and he loved getting the two together, which is all a good teacher really ever
has to do. On a cool fall day in Edmonton in 1963, he taught my Science 9 class
a basic lesson: the scientific method – what it says, how it works, and why it
gets the amazing results that it does. I’m sure that I have embellished the picture
in the years since that day, but basically, I recall clearly that on that day I
got the scientific method, which is to say I understood it, and it filled me with
hope.
I
saw that prior to the arrival of science in my society, when people had had a
question about some events in their lives – a question for which they had no
stock answers – they had consulted wise women and men who were supposed to be
able to give them answers. But often the answer was: “Because the gods decreed
it that way. Our lot in life is to accept their decrees, not question them.” In fact, people generally believed that the profound
truths of the universe were beyond reason and evidence, too complex for almost any
humans to grasp.
They
believed a few special people could see those truths by revelation, a rare state
of mind that was a gift that could not be attained by reason or discipline.
Lesser
truths – about how to deliver babies or keep goats healthy or similar practical
matters – could come to some minds via years of apprenticeship under a master of
midwifery or goat husbandry or whatever. But even the masters’ knowledge had come
via masters of previous generations. In other words, most of the tribe’s
knowledge was passed down like habits – older people training younger ones in
the knowledge and skills that the tribe had accumulated slowly over generations,
mostly by trial and error, not reason and not revelation.
Without
revelation, humans could grasp only these lesser truths. What right and wrong are
and why the cosmos exist weren’t matters for ordinary folk to understand. Instead,
those things were learned as dogma and accepted without logical explanation or question.
Some of each tribe’s knowledge was justified by something like science – by
reasoning and evidence, in other words – but much more was justified by religious
belief, with many ideas justified by bits of both. All of these then made up
the total conscious wisdom of the tribe.
And
many of every tribe’s ways weren’t conscious and weren’t justified at all; they
were customs so ingrained that no one raised in the tribe noticed them.
Each
tribe accumulated knowledge gradually over generations, and even then, a
tribe’s total stock of knowledge was small when compared to its ignorance.
The
scientific method changes this picture. With the scientific method – what Bacon
called the “Novum Organum” – people could go beyond explanations like “we’ve
always done it that way” or “the gods decreed it that way.” People could choose
to respond to a problem that they wanted to solve by first, studying it
closely, then forming a hypothesis about why it was the way it was, i.e.,
an explanation based on reasoning and evidence and pointing to possible causes
and effects for why events might be unfolding in the ways that they did.
Then,
if I were the seeker of understanding in this picture, I could imagine an experiment
by which I could test to see whether my hypothesis worked: that is, I could
imagine future circumstances in which – if my explanation of what was going on
was correct – I’d be able to predict what was going to happen next. Most of the
time, most hypotheses turned out to be wrong. But the seekers kept trying, and
once in a while they hit on a bit of knowledge that was amazingly useful. They
found a new way of looking at the world that worked so well that it gave them
new power to direct the events of their lives.
How
to make fire or how to make wheels were ideas of this breakthrough type, but
we’ll probably never know who first had those ideas. On the other hand, we’re fairly
certain it was Archimedes, a Greek scientist who lived and worked over 2200
years ago, who figured out how things can float in water. Anything wholly or
partly immersed in a liquid will be buoyed up by a force equal to the weight of
the liquid that it displaces. If the water displaced weighs more than the thing
being immersed, the thing will float. This was a very useful insight because it
enabled people who built ships to design the hulls of those ships with great
skill. By doing more testing, Greek shipbuilders learned to make fast, efficient
warships and cargo ships. Then, shipbuilding became very profitable in Ancient
Greece.
It
is useful to note here that any hypothesis that can’t be tested in this
physically observable way is not science. Science has no interest in untestable
hypotheses.
Note
that future circumstances about which I am making my prediction might be ones I
can set up at will. For example, if I hypothesize that using a longer lever will
increase the load that I can move, then when I get a longer lever under this
boulder I’m straining to remove from my field, I should be able to move that
boulder with the same force I had applied to my end of the first lever that
didn’t work just a few minutes ago.
Similarly,
if I have by coincidence found a new chemical substance that I think will kill
coddling moths, I can spray it into an enclosed chamber of a few cubic meters
of air set up in my lab, one in which I have already trapped a dozen or so adult
coddling moths crawling about on a small apple tree. If all the coddling moths
die in the space of a few hours, then I will be able to conclude, tentatively,
that I have found a new pesticide which kills coddling moths.
But
it is also worth noting here that there are some hypotheses for which I can’t
set up test conditions. Hypotheses in astronomy are clear examples of ones that
I can’t test in a lab whenever I want to. I can’t summon up a comet anytime I
please; I can’t check at will whether comets reflect more blue light than
yellow light. But comets large enough for me to study through my telescope do pass
by the earth every few years. I can test my hypothesis if I just show a little
patience and wait for the next one.
In
either case, when the phenomenon that I am interested in happens, if I am a
serious scientist, I will observe changes to the physical properties of the
things I am studying. I will carefully record all of my observations or data,
and after the events I’m watching are done, I will study my data to see whether
the outcome that I predicted would happen, did in fact happen as I said it
would.
Sometimes,
the prediction comes true in obvious ways, as when the coddling moths in the
chamber all die. Whether the pesticide I’ve found is safe for other species is
another question, but these moths are dead. With the longer lever, I can move
the stone I could not move before. Hypotheses can be confirmed.
Sometimes
the predictions made by scientists doing the experiment come true visibly, even
dramatically. But often in our era, the results of research are only observable
via instruments (microscopes, telescopes, etc.), and even then, only over very
long or very short timespans. Scientists today often use instruments to cause a
change to happen, then use more instruments to record data as they happen. They
save the recorded data and study them, and do calculations with them, after the
experiment is done.
Let’s
reiterate that in all cases – ones of large phenomenon or very tiny ones, very
fast or very slow ones – in order for a hypothesis to be considered scientific,
it must be observably testable. The experiment is set up so that the observations
will clearly either confirm or disconfirm the hypothesis. I’ll see the results I
predicted either clearly happen or clearly fail to happen.
Often,
what we find out is that we ought to be trying to steer nature with much more care
and nuance than we have been doing. For example, my moth-killing pesticide may also
cause birds in my area to die; this may allow other pests to breed rampantly.
Meanwhile, by more experiments I may learn that there are other species in the
orchard that control coddling moths without upsetting the natural balances there.
Today,
everything we know about nature is leading us to the conclusion that we can
affect natural balances, but we must learn to do so carefully if we don’t want
to cause side-effects that will be unpleasant for us. Thus, instead of using a
pesticide, I may choose to breed predator species that eat coddling moth eggs.
Then, if I release large numbers of these predators into my orchard, I may be
able to wipe out coddling moths in my whole area. And no toxic chemicals will
need to go into the orchard at all.
It
is also useful to say here that most humans are hypothesis-makers. We like to
try to figure things out, imagine possible explanations for events happening
around us. We have curious minds.
What
a mind is exactly can be hard to define. So I am going to postulate for
the purposes of this essay that all living things have at least a primitive
mind. I say this because research is telling us that even protozoa like amoeba
can learn new rules and change their behaviors when their worlds change. Thus,
I am going to describe, not define, what a mind is by saying it is a trait possessed
by any organism that is able to recognize patterns in events and then come to avoid
those events that will cause it damage or to pursue ones that hold opportunity.
All
living things can do this. How exactly they do – how living things learn and
know – we so far can’t characterize in simpler terms. But we see their actions.
But
why should we have to give simpler definitions? All realms of knowledge begin
from definitions of a few basic terms that are considered self-evident and
necessary if that field of knowledge is to be explained. Terms like “point” or
“line” in Geometry; “mass” and “force” in Physics. Etc.
So
let’s propose for this essay’s sake that mind is a quality any entity
has if it can learn from experience to change its ways of behaving so as to
avoid hazards and pursue opportunities relevant to its own well-being.
What
the scientific method did for our more curious ancestors – when they kept it in
mind – is that it gave them a systematic series of steps to follow, steps that
would lead them to more and more models and theories that worked better and
better for predicting results of recognized patterns in events. Such models
then enabled them to steer events in nature or steer around them and,
consequently, to live healthier, safer, more satisfying lives.
The
overall conclusion to be drawn from this discussion of the scientific method,
however, is that it offers us a path toward better and better understanding of the
things in our universe. I got that at thirteen years old. I could see, via many
examples, that the scientific method works. It gives us more and more control over
nature, and thus, over our lives.
For
all of my years since that day, I have believed that, given some time, science can
solve every problem we humans encounter. Sometimes, it does not give us exact laws
that enable us to make exact predictions. Instead, in many fields, a new theory
only gives statistical laws that may be used to predict the odds of some event
occurring. But statistical laws are still science, not superstition.
For
example, a theory of how hurricanes occur won’t enable scientists to stop a hurricane
from making landfall or even say how many there will be in the next three
months. But once a hurricane is developing in the open ocean, the theory may enable
the scientists to say, day by day, that the odds that a hurricane will hit the
coast are growing to near certainty. They can even predict where it will hit a
day before it does so. Then, people can be warned to get out of its way.
No
cancer research can yet say for sure which of us will get cancer, but research
can tell us that our odds of getting cancer drop by over half if we quit
smoking.
In
addition, note that if testing shows a theory sometimes leads us to predictions
that don’t work, the next step is not to halt research on that theory. The next
step is to test the theory further by experiments designed to reveal why it is only
working some of the time. Scientific testing – if it truly fits the term “scientific”
– always points the way to more and better science.
Science
is not now and never will be complete. It’s always telling us to think and test
more precisely. Form new models and theories; test them in subtler ways. We’re
never done with any problem in science, but our theories and our ways of
testing them get more and more nuanced and focused.
(credit: Wikipedia)
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