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

DEFINITION. 187
fundamenta divisionis; for each quality common to the
whole class, each of mutual resemblance"
"point among the
members of the class, is a distinct possible basis of division.
We will add a few examples ; and, first, of processes
which resemble division,
"
(a) Ireland into Ulster, Munster,
Leinster, and Connaught." This is not logical division, but
physical
a physical object. A division of
"
partition," the distinction of the various parts of
men," c., would be correct by
"
Irishmen" into
"
Ulster-
the rules. (6) "Mind into
thought, feeling, and will ; body into extension, resistance,
weight," &c. Neither of these is a logical division ; both
are examples of scientific analysis, (c)
right-angled, acute-angled, obtuse-angled."
Triangle into
Correct logical
division, exclusive (one basis, the size of the angles
as compared with a right -
angle), and exhaustive, (d)
"
Churches into Gothic, Episcopal, High, and Low." Here
are three bases of division, architecture, government, and
dogma ;
of each.
and no account is taken of the many different kinds
EXERCISE XIII.
(1) Are Definition and Division both necessary to the
full understanding of the meaning of a term? Give reasons
for your answer. [O.]
(2) How, for purposes of logical theory, would you deter
mine the notion of a class ?
(3) State and explain any general rules needed for classi
fication beyond those given for "logical division."
(4) Examine critically the distinction of
"
"
"
Natural and
"
"Artificial in Classification. Of which kind is the arrange
ment of books according to their subjects ?
(5) Explain
"
fundamentum divisionis" and "cross
division," and give examples of each. [O.]
(6) Examine the following divisions : (a) Religions into
true and false ; (6) beings into material and spiritual ; (c)
geometrical figures into rectilinear and non-rectilinear : (d)
students into those who are idle, those who are athletic, and
those who are diligent.
10. An important traditional method of division,
known as Dichotomy (called by Aristotle