Some authorities, holding special theories regarding the nature of mind, hold that Thought-Culture is merely a _training_ of the faculties rather than a _creation_ of new mental power, inasmuch as the mind cannot be built up from the outside. This is a curious combination of truth and error. It is true that the mind cannot be built up from outside material, in the sense of creating _new mind_, but it is also true that in every mind there is the potentiality of growth and development. Just as the future oak is said to be in the acorn, so are the potentialities of mind-growth in every mind waiting for nourishment from outside and the proper cultivation. Brooks has well stated this, as follows: "The culture of the mind is not creative in its character; its object is to develop existing possibilities into realities. The mind possesses innate powers which may be awakened into a natural activity. The design of culture is to aid nature in improving the powers she has given. No new power can be created by culture; we can increase the activity of these powers, but cannot develop any new activities. Through these activities new ideas and thoughts may be developed, and the sum of human knowledge increased; but this is accomplished by a high activity of the natural powers with which the mind is endowed, and not by the culture of new powers. The profound philosopher uses the same faculties that the little child is developing in the games of the nursery. The object of culture is to arouse the powers which nature has given us into a normal activity and to stimulate and guide them in their unfolding." In connection with the objection above mentioned, it may be said that while the development of the mind must come from within itself, rather than from without, nevertheless, in order to develop, it must have the nourishing material from the outside world in order to grow. Just as the body can grow from within only by the aid of nourishment from outside, so the mind, while growing from within, needs the material for thought which can come only from without itself. Thought requires "things" upon which to exercise itself--and upon which it is nourished. Without these outside objects, it can have no exercise and can receive no nourishment. Thought consists in the perception, examination and comparison of _things_, and the consequent building up new combinations, arrangements and syntheses. Therefore, the perceptive faculties are most necessary to Thought, and their culture is most necessary in the general work of Thought-Culture.