part ii: feynman's ideas about "what is science" page 10 --
If
you ask a child what makes the toy dog move, you should think about what an
ordinary human being would answer.
The
answer is that you wound up the spring; it tries to unwind and pushes the gear
around.
What a good way to begin a science course.
Take apart the toy; see how
it works.
See the cleverness of the
gears; see the ratchets.
Learn something about the
toy, the way the toy is put together, the ingenuity of people devising the
ratchets and other things.
That's good.
The question is fine.
The answer is a little
unfortunate, because what they were trying to do is teach a definition of what
is energy.
But nothing whatever is
learned.
Suppose a student would say,
"I don't think energy makes it move."
Where does the discussion go
from there ?
I finally figured
out a way to test whether you have taught an idea or you have only taught a
definition.
Test it this way:
You say, "Without using
the new word which you have just learned, try to rephrase what you have just
learned in your own language." Without using the word "energy,"
tell me - what you know now about the dog's motion." You cannot. So you
learned nothing about science. That may be all right. You may not want to learn
something about science right away. You have to learn definitions. But for the
very first lesson is that not possibly destructive ?
I think, for lesson number
one, to learn a mystic formula for answering questions is very bad. The book
has some others -"gravity makes it fall;" "the soles of your
shoes wear out because of friction." Shoe leather wears out because it
rubs against the sidewalk and the little notches and bumps on the sidewalk grab
pieces and pull them off. To simply say
it is because of friction, is sad, because it's not science. My father
dealt a little bit with energy and used the term after I got a little bit of
the idea about it
(A-HA - THE CONCEPT INTRODUCTION PHASE OF THE LEARNING CYCLE).
What he would have done I know, because he did in fact essentially the same
thing-though not the same example of the toy dog.
He would say,
"It moves because the sun is shining,"
if he wanted to give the
same lesson. I would say "No. What has that to do with the sun shining?
It moved because I wound up
the springs."
"And why, my friend,
are you able to move to wind up the spring?"
"I eat."
"What, my friend, do
you eat?" "I eat plants."
"And how do they
grow?" "They grow because the sun is shining."
And it is the same with the
dog. What about gasoline ? Accumulated energy of the sun which is captured by
plants and preserved in the ground. Other examples all end with the sun. And so
the same idea about the world that our textbook is driving at is phrased in a
very exciting way.
page 11 -- All the things that we see that are moving, are moving because the
sun is shining. It does explain the relationship of one source of energy to
another, and it can be denied by the child. He could say, "I don't think
it is on account of the sun shining," and you can start a discussion. So
there is a difference. ( Later I could challenge him with the tides, and what
makes the earth turn, and have my hand on mystery again. )
That is just an example of the difference between definitions
(which are necessary) & science.
The only objection in this
particular case was that it was the first lesson. It must certainly come in
later, telling you what energy is, but not to such a simple question as
"What makes a dog move?" A child should be given a child's answer.
"Open it up; let's look at it."
During those walks in the
woods, I learned a great deal. In the case of birds, for example, I already
mentioned migration, but I will give you another example of birds in the woods.
Instead of naming them, my father would say, "Look, notice that the bird is
always pecking in its feathers. It pecks a loutin its feathers. Why do you
think it pecks the feathers?"
I guessed it's because the
feathers are ruffled, and he's trying to straighten them out.
He said, "Okay, when
would the feathers get ruffled, or how would they get ruffled ?"
"When he flies. When he
walks around, it's okay; but when he flies it ruffles the feathers."
Then he would say, "You
would guess then when the bird just landed he would have to peck more at his
feathers than after he has straightened them out and has just been walking
around the ground for a while. Okay, let's look."So we would look, and we
would watch, and it turned out, as far as I could make out, that the bird
pecked about as much and as often no matter how long he was walking an the ground
and not just directly after flight. So my guess was wrong, and I couldn't guess
the right reason. My father revealed the reason.
It is that the birds have lice.
There is a little flake that
comes off the feather, my father taught me, stuff that can be eaten, and the
louse eats it. And then an the loose, there is a little bit of wax in the
joints between the sections of the leg that oases out, and there is a mite that
lives in there that can eat that wax. Now the mite has such a good Source of
food that it doesn't digest it too well, so from the rear end there comes a
liquid that has too much sugar, and in that sugar lives a tiny creature, etc.
page 12 -- The facts are not
correct. The spirit is correct.
First I learned about
parasitism, one on the other, on the other, on the other. Second, he went on to
say that in the world whenever there is any source of something that could be
eaten to make life go, some form of life finds a way to make use of that source;
and that each little bit of left over stuff is eaten by' something.
Now the point of this is that the result of observation, even
if I were unable to come to the ultimate conclusion, was a wonderful piece of
gold, with marvelous results.
Suppose I were told to
observe, to make a list, to write down, todo this, to look, and when I wrote my
list down, it "as filed with 130 other lists in the back of a notebook. I
would learn that the result of observation is relatively dull, that nothing
much comes of it.I think it is very important - at least it was to me - that if
you are going to teach people to make observations, you should show that
something wonderful can come from them.
I learned then what science was about. It was patience.
If you looked, and you
watched, and you paid attention, you got a great reward from it ( although
possibly not every time ). As a result, when I became a more mature man, I
would painstakingly, hour after hour, for years, work on problems-sometimes
many years, sometimes shorter times-many of them failing, lots of stuff going
into the wastebasket; but every once in a while there was the gold of a new
understanding that I had learned to expect when I was a kid, the result of
observation. For I did not learn that observation was not worthwhile.
Incidentally, in the forest we learned other things.
We would go for walks and
see all the regular things, and talk about many things; about the growing
plants, the struggle of the trees for light, how they try to get as high as
they can, and to solve the problem of getting water higher than 35 or 40 ft.,
the little plants on the ground that look for the little bits of light that
come through, all that growth, and so forth.
One day after we had seen all this, my father took me to the forest again and said, "In all this time we have been looking at the forest we have only seen half of what is going on, exactly half."
I said, "What do you
mean ?" He said, "We have been looking at how all these things grow;
but for each bit of growth, there must be the same amount of decay, otherwise
the materials would be consumed forever. Dead trees would lie there having used
up all the stuff from the air, and the ground, and it wouldn't get back into
the ground or the air, sod nothing else could grow, because there is no
material available. There must be for each bit of growth exactly the same
amount of decay."
page 13 -- There then
followed many walks in the woods during which we broke up old stumps, saw
frizzy bags and funguses growing-he couldn't show me bacteria, but we saw the
softening effects, and so on. I saw the forest as a process of the constant
turning of materials. There were many such things, descriptions of things, in
odd ways. He often started to talk about things like this: "Suppose a man
from Mars were to come down and look at the world. For example when I was
playing with my electric trains, he told me that there is a great wheel being
turned by water which is connected by filaments of copper, which spread out and
spread out and spread out in all directions; and then there are little wheels,
and all those little wheels turn when the big wheel turns.
The relation between them is
only that there is copper and iron, nothing else, no moving parts. You turn one
wheel here, and all the little wheels all over the place turn, and your train
is one of them.
It was a wonderful world my father told me about.
You might wonder what he got
out of it all.
I went to MIT.
I went to Princeton.
I came home, and he said,
"Now you've got a science education. I have always wanted to know
something that I have never understood; and so, my son, I want you to explain
it to me. I said yes.He said, "I understand that they say that light is
emitted from an atom when it goes from one state to another, from an excited
state to a state of lower energy.I said, "That's right." "And
light is a kind of particle, a photon, I think they call it."
"Yes.""So if the photon comes out of the atom when it goes from
the excited to the lower state, the photon must have been in the atom in the
excited state." I said, "Well, no." He said, "Well, how do
you look at it so you can think of a particle photon coming out without it
having been in there in the excited state?"I thought a few minutes, and I
said, "I'm sorry; I don't know. I can't explain it to you." He was
very disappointed after all these years and years of trying to teach me
something, that it came out with such poor results.
What science is, I think, may be something like this:
There was an this planet an
evolution of life to a stage that there were evolved animals, which are
intelligent. I don't mean just human beings, but animal which play and which
can learn something from experience (like cats ). But at this stage each animal
would have to learn from its own experience. They gradually develop, until some
animal could learn from experience more rapidly and could even learn from
another's experienceby watching, or one could show the other, or he saw what
the other one did.
page 14 -- So there came a
possibility that all might learn it, but the trans- mission "'as
inefficient and they would die, and maybe the one who learned it died too,
before he could, pass it on to others.
Science is the belief in the ignorance of experts.
Leyden note:
remember the great december illinois earthquake scare a few years ago ? It
occurred because an expert said it would. He was an "expert" -- and
everyone bought earthquake insurance. )
The question is: is it possible to learn more rapidly what somebody learned from some
accident than the rate at which the thing is being forgotten, either because of
bad memory or because of the death of the learner or inventors ?
So there came a time,
perhaps, when for some species the rate at which learning was increased,
reached such a pitch that suddenly a completely new thing happened; things
could be learned by one individual animal,
passed on to another, and
another fast enough that it was not lost to the race. Thus became possible an
accumulation of knowledge of the race. This has been called time-binding. I
don't know who first called it this. At any rate, we have here some samples of
those animals, sitting here trying to bind one experience to another, each one
trying to learn from the other.
This phenomenon of having a
memory for the race, of having an accumulated knowledge passable from one
generation to another, was new in the world. But it had a disease in it. It was
possible to pass on ideas which were not profitable for the race. The race has
ideas, but they are not necessarily profitable. So there came a time in which
the ideas, although accumulated very slowly, were all accumulations not only of
practical and useful things, but great accumulations of all types of
prejudices, and strange and odd beliefs. Then a way of avoiding the disease was
discovered. This is to doubt that what is being passed from the past is in fact
true, and to try to find out ab initios again from experience, what the
situation is, rather than trusting the experience of the past in the form in
which it is passed down. And that is what science is; the result of the
discovery that it is worthwhile rechecking by new direct experience, and not
necessarily trusting the race experience from the past. I see it that way. That
is my best definition . I would like to remind you all of things
that you know very well in order to give you a little enthusiasm. In religion, the
moral lessons are taught, but they are not just taught once, you are inspired
again and again, and I think it is necessary to inspire again and again, and to
remember the value of science for children, for grown-ups, and everybody else,
in several ways; not only that we will become better citizens, more able to
control nature and so on. There are other things.
page 15 -- There is the value
of the world view created by science. There is the beauty and the
wonder of the world that is discovered through the results of these new
experiences. That is to say, the wonders of the content which I just reminded
you of; that things move because the sun is shining. (Yet, not everything moves
because the sun is shining. The earth rotates independent of the sun shining,
and the nuclear reaction recently produced energy on the earth, a new source.
Probably volcanoes are generally moved from a source different from the shining
son.)
The world looks so different after learning science.
For example, trees are made
of air, primarily. When they are burned, they go back to air, and in the
flaming heat is released the flaming heat of the sun which was bound in to
convert the air into tree, and in the ash is the small remnant of the part
which did not come from air that came from the solid earth, instead. These are
beautiful things, and the content of science is wonderfully full of them. They
are very inspiring, and they can be
used to inspire others.
Another of the qualities of
science is that it teaches the value of rational thought as well as the
importance of freedom of thought; the positive results that come from doubting
that the lessons are all true. You must here distinguish-especially in
teaching-the science from the forms or procedures that are sometimes used in
developing science. It is easy to say, 'We write, experiment, and observe, and
do this or that." You can copy that form exactly. But great religions are
dissipated by following form without remembering the direct content of the
teaching of the great leaders. In the same way, it is possible to follow form
and call it science, but that is pseudo-science.
In this way, we all suffer from the kind of tyranny we have today in the many
institutions that have come under the influence of pseudo-scientific advisers.
We have many studies in teaching, for example, in which people make
observations, make lists, do statistics, and so on, but these do not thereby
become established science, established knowledge. They are merely an imitative
form of science-analogous to the South Sea islands airfields, radio towers,
etc. made out of wood. The islanders expect a great airplane to arrive. They
even build wooden airplanes of the same shape as they see in the foreigner's
airfields around them, but strangely enough, their wood planes do not fly. The
result of this pseudoscientific imitation is to produce experts, which many of
you are. You teachers who are really teaching children at the bottom of the
heap can maybe doubt the experts.
page 16 -- As a matter of
fact, I can also define science another way:
Science is the belief in the ignorance of experts.
When someone says,
"Science teaches such and such," he is using the
word incorrectly.
Science doesn't teach anything; experience teaches it.
If they say to you,
"Science has shown such and such," you might ask, "How does
science show it?
How did the scientists find
out ? -- How ? -- What ? -- Where ?" ----- PROCESS SCIENCE
It should not be
"science has shown" but "this experiment, this effect, has
shown." And you have as much right as anyone else, upon hearing about the
experiments (but be patient and listen to all the evidence) to judge whether a
sensible conclusion has been arrived at.
In a field which is so
complicated that true science is not yet able to get anywhere, we have to rely
on a kind of old-fashioned wisdom, a kind of definite straightforwardness. I am
trying to inspire the teacher at the bottom to have some hope, and some
self-confidence in common sense and natural intelligence. The experts who are
leading you may be wrong.
I have probably ruined the
system, and the students that are coming into Caltech no longer will be any
good. I think we live in an unscientific age in which almost all the buffeting
of communications and television words, books, and so on are unscientific. As a
result, there is a considerable amount of intellectual tyranny in the name of
science.
Finally, with regard to this
time-binding, a man cannot live beyond the grave. Each generation that
discovers something from its experience must pass that on, but - it must pass
that on with a delicate balance of respect and disrespect, so that the race
(now that it is aware of the disease to which it is liable) does not inflict
its errors too rigidly on its youth, but it does pass on the accumulated
wisdom, plus the wisdom that it may not be wisdom.
It is necessary to teach
both to accept and to reject the past with a kind of balance that takes
considerable skill. Science alone of all the subjects contains within itself
the lesson of the danger of belief in the infallibility of the greatest
teachers of the preceding generation. So carry on. Thank you.
6/18s/95 -- 11/12s/95 --
4/13st/96 6/14/11 19 years later