256 An Essay on the Signs of Ideas. 
that the effect of the wind in impelling a 
ship through the sea is power; another will 
repeat the trite, but not less correct, and beau- 
tiful saying, that ‘“‘ Knowledge is power.” 
In short, such words as the word power, are 
abbreviated terms, which may stand for almost 
any set of ideas which the hearer chooses. 
When I mention the word time, one hearer 
will think of the progress of the sun from 
east to west; another of the increase and 
waning of the moon; a third of the motion 
of the shadow on the sun-dial; and every 
different bearer will have a different set of 
ideas. So that of the word time we have no 
single idea; it evidently stands for any one 
out of numerous trains of ideas, representing 
various phenomena, which we have, on diffe- 
rent occasions, witnessed. 
When the word gratitude is mentioned, I 
endeavour to recollect instances which I have 
observed of what is commonly called grati- 
tude. I see, in my mind’s eye, one person 
conferring a kindness, and the other soon 
after returning it. So that the word grati- 
tude serves merely to excite ideas of certain 
transactions to which we apply that term. 
The words memory, imagination, judg- 
ment, if rightly understood, will be found to 
be merely abbreviated terms, expressive of 
