LATIN AND GREEK NUMERALS. 
27 
and Latin numerals. In our next lecture we shall commence, 
by this necessary preparation for comprehending the meaning 
of the names of classes and orders ; and shall then explain their 
characters, and illustrate the same by drawings. Sensible ob- 
jects are of great assistance to the mind, by enabling it to form 
definite ideas of the meaning of words. In most abstract stud- 
ies we cannot have such aid ; and in order to comprehend in- 
structions given upon them it is necessary that the meanings of 
words should be well understood. Young people, and indeed 
sometimes those who are not very young, seem to think a gene- 
ral idea of the meaning of abstract terms, is sufficient : thus 
they speak of “ a sensation of pity,” when they mean an emo- 
tion. A more critical knowledge of the meaning of words, 
would enable them to perceive, that sensation is a term appro- 
priated to that state of the mind which immmediately follows 
the presence of an external object : it depends on the connexion 
between the body and the mind. The mind separated from all 
the organs of sense, could have no sensation ; but it could have 
emotions, for they are feelings which the mind has, independ- 
ently of the senses. 
The great advantage of pursuing studies which relate to ma- 
terial objects, is, as we have before remarked, in being able to 
illustrate principles, and define terms by a reference to those ob- 
jects or to delineations of them. 
LECTURE IV. 
Latin and Greek numerals. — Artificial classes and orders. 
We shall now present you with a list of Latin and Greek 
numerals, which it is necessary to commit to memory, in order 
that you may understand the names given to the classes and 
orders. It is not in Botany alone, that a knowledge of these nu- 
merals will be useful to you ; very many words in our common 
language are compounded with them ; for example — uniform , 
from unus, one, and forma , form ; octagon, a figure having 
eight corners ; hexagon, having six corners ; pentagon, having 
five corners ; decimal, from decern, ten. These very few ex- 
amples may show you the importance of knowing these numer- 
Assistance which the mind derives from sensible objects — Example of 
using terms indefinitely. Importance of understanding- Latin and Greek 
numerals. 
