An Essay on the Signs of Ideas. 253 
or person, all who are acquainted with that 
person, or that house, or that horse, (allow- 
ing that no change has taken place in those 
objects, ) will have similar ideas raised by that 
name. 
When speaking, however, of objects of a 
different kind, such, for instance, as are ag- 
gregates for ever varying in their mutual rela- 
tions, number, form, and appearance, such 
as are liable to rapid changes, or such as have 
never been witnessed by both the hearer and 
speaker, the chances are as infinity to one 
that no two persons are contemplating the 
same set of ideas. This may be observed to 
be in a remarkable degree the case in our 
conception of poetical-descriptions, and thus, 
we see, why, imitation apart, any character 
of a drama must be differently conceived, 
and of course differently represented, by every 
new actor who undertakes it. 
Moreover, such is the necessary mechan- 
ism of language, that it is impossible for us 
to have a name proper for each individual 
idea, or set of ideas. The business of life 
could not, with such an arrangement, have 
gone on with the requisite rapidity. On this 
account, names have been generalized; and 
when thie appellations tree, horse, man, had 
been given to one individual of each of these 
