12 Owen—Meaning and Function of Thought-Connectives. 
duces. Mere contact is not sufficient. Two balls are not con¬ 
ceived as joined by the mere contact of their surfaces. Indeed in 
one view contact is needless. The two balls of a dumb-bell are 
conceived as joined by the handle, though they themselves are 
each at some distance from the other. Yet the molecular con¬ 
tinuity is maintained throughout the total mass. 
This illustration may be viewed in another way, which will, 
I believe, be found more helpful. The handle and one ball may 
conveniently be taken as forming one total. The handle and the 
other ball form another total. The handle is then a common 
factor of both totals. As it is obviously possible to take the 
same view of all joined bodies, the condition of junction may 
be defined as the possession of a common factor. 
The common factor may vary in size from that of either body 
(or both) down to nothing. The cases which develop from such 
variation have been carefully distinguished and are well known as 
Inclusion: the common factor is the greatest possible part 
(i. e. all) of one body; or, the common factor is the greatest 
possible part (i. e. all) of the other body; 
Coincidence: the common factor is the greatest possible part 
(i. e. all) of both bodies; 
Exclusion: the common factor is the smallest possible part of 
one body or of the other body or of both. 1 
1 These cases may be conveniently developed as follows: Let two areas 
overlap each other thus: 
C being the common factor, A + C one area and C -f B the other. 
(1) Let C be increased to the value of A + C; or, what is more conven¬ 
ient, let A + C be diminished to C. The right hand area now includes 
all of the left. 
(2) Conversely, let C + B be diminished to C. The left hand area now 
includes all of the right. 
(3) Let C be increased to the value of A -f- C and of C + B. The 
possibility of this presupposes the equality of the two areas. For con- 
