From G.K. Chesterton’s St. Thomas Aquinas:
But many modern people talk as if what they call induction
were some magic way of reaching a conclusion, without using
any of those horrid old syllogisms. But induction does not lead
us to a conclusion. Induction only leads us to a deduction.
Unless the last three syllogistic steps are all right, the conclusion
is all wrong. Thus, the great nineteenth century men of science,
whom I was brought up to revere (“accepting the conclusions
of science”, it was always called), went out and closely
inspected the air and the earth, the chemicals and the gases,
doubtless more closely than Aristotle or Aquinas, and then
came back and embodied their final conclusion in a syllogism.
“All matter is made of microscopic little knobs which are indivisible.
My body is made of matter. Therefore my body is made of microscopic
little knobs which are indivisible.” They were not wrong in
the form of their reasoning; because it is the only way to reason.
In this world there is nothing except a syllogism–and a fallacy.
But of course these modern men knew, as the medieval men knew,
that their conclusions would not be true unless their
premises were true. And that is where the trouble began.
For the men of science, or their sons and nephews,
went out and took another look at the knobby nature of matter;
and were surprised to find that it was not knobby at all.
So they came back and completed the process with their syllogism;
“All matter is made of whirling protons and electrons.
My body is made of matter. Therefore my body is made of whirling
protons and electrons.” And that again is a good syllogism;
though they may have to look at matter once or twice more,
before we know whether it is a true premise and a true conclusion.
But in the final process of truth there is nothing else except
a good syllogism. The only other thing is a bad syllogism;
as in the familiar fashionable shape; “All matter is made of protons
and electrons. I should very much like to think that mind is much
the same as matter. So I will announce, through the microphone
or the megaphone, that my mind is made of protons and electrons.”
But that is not induction; it is only a very bad blunder
in deduction. That is not another or new way of thinking;
it is only ceasing to think.
Extracts 