Conclusion 257 
boughs and leaves ; this is a kind of locomotion ; and, as 
Dr. Erasmus Darwin long since pointed out, they do some- 
times approach nearly to what may be called travelling ; 
a man of consistent character will never look at a bough, 
a root, or a tendril without regarding it as a melancholy 
and unprincipled compromise ” (New edition, Pp. 153). 
Having called attention to this view, and commended 
it to the consideration of my readers, I proceed to another 
which should not have been left to be touched upon only in 
a final chapter, and which, indeed, seems to require a book 
to itself—I refer to the origin and nature of the feelings, 
which those who accept volition as having had a large share 
in organic modification must admit to have had a no less 
large share in the formation of volition. Volition grows out 
of ideas, ideas from feelings. What, then, is feeling, and the 
subsequent mental images or ideas ? 
The image of a stone formed in our minds is no repre- 
sentation of the object which has given rise to it. Not 
only, as has been often remarked, is there no resemblance 
between the particular thought and the particular thing, 
but thoughts and things generally are too unlike to be 
compared. An idea of a stone may be like an idea of 
another stone, or two stones may be like one another ; 
but an idea of a stone is not like a stone; it cannot be 
thrown at anything, it occupies no room in space, has no 
specific gravity, and when we come to know more about 
stones, we find our ideas concerning them to be but rude, 
epitomised, and highly conventional renderings of the actual 
facts, mere hieroglyphics, in fact, or, as it were, counters or 
_bank-notes, which serve to express and to convey commod- 
ities with which they have no pretence of analogy. 
Indeed we daily find that, as the range of our perceptions 
becomes enlarged either by invention of new appliances or 
after use of old ones, we change our ideas though we have 
no reason to think that the thing about which we are 
thinking has changed. In the case of a stone, for instance, 
R 
