Page:Collected Works of Dugald Stewart Volume 3.djvu/216

200 tually man, and every other species of animal either existing or that may exist : But the genus animal is contained in man, and in other animals actually ; for man cannot exist without being in actuality, and not potentially only an animal." If we have recourse to Dr. Gillies for a little more light upon this question, we shall meet with a similar disappointment. According to him, the meaning of the phrases in question is to he sought for in the following definition of Aristotle:- "To say that one thing is contained in another, is the same as saying that the second can be predicated of the first in the full extent of its signification; and one term is predicated of another in the full extent of its signification, when there is no particular denoted by the subject, to which the predicate does not apply." In order, therefore, to make sure of Aristotle's idea, we must substitute the definition instead of the thing defined, that is,