The Indianapolis times. [volume] (Indianapolis [Ind.]) 1922-1965, 1933-10-31
-Dietz on Science
SCIENCE BOWS
TO SECONDARY
LAWS CONTROL
Too improbable Replaces
Impossible as Basic
Rule in Physics.
BY DAVID DIETZ
Scripps Howard Science Editor

Let us review the argument
quickly for those who are just join
ing the seminar on determinism
Sir Arthur Eddington, famous Brit
ish astronomer, says that science
has given up determinism which for
200 years has been the fundamental
philosophy of science.
He points out that there are two
kinds of scientific laws: primary
laws say certain things can not
happen because they are impossible;
secondary laws say certain things
can not happen because they are
too improbable. Science has discov-
cred now that it needs secondary
laws only. Nothing is fundamentally
impossible any more, merely too i'm
probable.
Now let us go on with the argu-
ment:
"IndeterminiStic or secondary law
accounts for Irregularities of expert
ence," Sir Arthur continues, so that
it can be used for predicting the
future as satisfactorily as primary
law. The predictions and regulari-
ties refer to average behavior of the
vast number of particles concerned
in most of our observations.
From Prediction to Gamble
When we deal with fewer par
ticles the indeterminacy begins to
be appreciate, and prediction be-
comes more of a gamble; till finally
the behavior of a single atom or
electron has a very large measure
of indeterminacy."
1t has been said frequently that
the physicists inability to tell what
an electron will do next is merely
result of his own ignorance about
the nature of an electron and that
if he knew more about the char
acteristics of an electron, he would
be able to say what the electron
was gong to do next. Eddington
disagrees with this view But before
answering it, he asks us to give a
little thought to the nature of our
knowledge of the physical universe
That knowledge, he points out, is
inferential knowledge.
Universe Banks knowledge
"All our knowledge of physical OBJ
iectS is by inference" he says. "Our
minds have no means of getting into
direct contact with them; but the
objects emit and scatter light waves,
and they are the source of pressures
transmitted through adjacent mate
rial. They are like broadcasting sta
lions that sent out signals which
we can receive.
AT one stage of the transmission
the signals pass along nerves within
our bodies. Ultimately visual. tao
tual, and other sensations are pro-
voked in the mind
The image which arises in the
mind is not the physical object.
though it is a source of information
about the physical object: to con-
fuse the mental object with the
physical object is to confuse the
clew with the criminal Life would
be impossible if there were no kind
OF correspondence between the ex-
ternal world and the picture of il
in our minds"
The physicist, however, Eddingtor
warns us, can not accept a rough
correspondence between mental pic.
ture and external object "Ir
physics" he says, I'VE do not accept
any detail of the picture unless il
is confirmed by more exact method,
of inference.
Doctrine illustrated
THE external world of physics /,
thus a universe populated with in.
ferenceS. The differences differ il
degree and not in kind.
In the universe of differences
past, present, and future appea,
simultaneously and it requires sci
entlfic analysis to osrt them out.
OF particular Importance to tn,
problem of determinism are our in
terences about the past. Strict!
speaking our direct differences from
sight, sound, touch, all relate to .
time slightly antecedent; but Otter
the lag is more considerable.
Suppose that we wish to discover
the constituents of a certain salt
We put it in test tube, apply Ger.
tain reagents, and ultimately reacf
the conclusion that it was silvel
nitrate. 1t is no longer silver nitrat,
after our treatment of it. This il
an example of retrospective infer
ence: The property which we infe1