Single Relations Between Thoughts. 
33 
In full, then, “A is the grandfather of B equivalently to A’s 
being the father of B’s father. ” 
Accordingly “ or ” reinstates the preceding thought and also 
names a reverse relation between it and the succeeding thought. 
The relation and reinstatement combine as adjunct of the last 
thought, being expressed by an adverb to the last verb. 
Of the word “ rather ” it should be noted that it names a 
relation of essential equivalence in meaning, but characterized 
by a preference for the latter of two forms of expression. Thus: 
“ A is the father of B’s father. Rather, A is B’s grandfather. ” 
The latter, then, is to the former in the relation of preferred 
equivalent to rejected equivalent. 
CLASS IV. RELATIONS OP ALTERNATIVE TO ALTERNATIVE. 
This class employs the connectives or, or else, otherwise, 
RATHER. 
For example: “A is the father of B. Or A is the uncle of B. ” 
In the preceding case attention was concentrated upon form of 
thought-expression. In the present case attention is with¬ 
drawn from form of expression and centered on the thoughts 
themselves. The hearer is presented with two (or more) possi¬ 
bilities, of which it is believed that one only is true; but 
which is true is not known. When strictly employed, as in the 
logical dilemma, these possibilities are exhaustive, and hence 
mutually exclusive. Accordingly, the truth of one involves the 
untruth of the other, and vice versa. But the linguistic method 
is commonly the following: the first thought is put as true; 
the second thought is then put as true in case the first is, after 
all, not true. 
Recalling our illustration, “A is the father of B. Or A is the 
uncle of B, ” let the relation of terms above described be known 
as alternative. Plainly, this relation does hold between the 
two propositions: first, that A is B’s father; second, that he is 
his uncle. It is, further, from the word “ or ” that this rela¬ 
tion is learned. Again and obviously, this relation cannot be 
perceived unless both its terms are in mind. The full meaning 
of the second sentence is then: “alternatively to A’s being B’s 
father, A is B’s uncle. ” The first thought having, as usual, 
