An introductory text-book of logic - Mellone, Sydney - Rare Books at ...

THE GENERAL NATURE OF INDUCTION. 231
them may occur at future times or in distant parts of
the earth or other regions of the universe. When com
plete enumeration of them all is impossible, the Induc
tion is called
"
This crow is black, arid
"
"
:
imperfect
that one, and that one, up to all that I have seen or
heard of; therefore all crows (without exception) are
black." The scholastic
"
imperfect induction
"
consists
essentially in enumerating all the known or observed cases
of some object S, and, if it is found that each of them
is P, inferring that every S, known and unknown, is P.
The process rests on observation and counting, and
nothing more.
This scholastic induction was vigorously attacked by
Bacon and Mill. Mill says, for instance, that Perfect
the con
Induction is of no scientific value whatever;
clusion is only a reassertion in briefer form of the
premises. To this Jevons has well replied :
"
That if
Perfect Induction were no more than a process of
abbreviation, it is yet of great importance, and requires
to be continually used in science and common life.
Without it we could never make a comprehensive state
ment, but should be obliged to enumerate every par
ticular. After examining the books in a library and
finding them to be all English books, we should be
unable to sum up our results in the one proposition,
"
"
all the books in this library are English books ;
but
should be required to go over the list of books every
time we desired to make any one acquainted with the
contents of the library. The fact is, that the power of
expressing a great number of particular facts in a very
brief space is essential to the progress of science. Just
as the whole art of arithmetic consists in nothing but a
series of processes for abbreviating addition and sub
traction, and enabling us to deal with a great number