§ 91. The activity of Perception results in the formation of an internal picture or image of its ideas which intelligence can call up at any time without the sensuous, immediate presence of its object, and thus, through abstraction and generalization, arises the conception. The mental image may (1) be compared with the perception from which it sprang, or (2) it may be arbitrarily altered and combined with other images, or (3) it may be held fast in the form of abstract signs or symbols which intelligence invents for it. Thus originate the functions (1) of the verification of conceptions, (2) of the creative imagination, and (3) of memory; but for their full development we must refer to Psychology. § 92. (1) The mental image which we form of an object may be correct; again, it may be partly or wholly defective, if we have neglected some of the predicates of the perception which presented themselves, or in so far as we have added to it other predicates which only seemingly belonged to it, and which were attached to it only by its accidental empirical connection with other existences. Education must, therefore, foster the habit of comparing our conceptions with the perceptions from which they arose; and these perceptions, since they are liable to change by reason of their empirical connection with other objects, must be frequently compared with our conceptions previously formed by abstractions from them. § 93. (2) We are thus limited in our conceptions by our perceptions, but we exercise a free control over our conceptions. We can create out of them, as simple elements, the manifold mental shapes which we do not treat as given to us, but as essentially our own work. In Pedagogics, we must not only look upon this freedom as if it were only to afford gratification, but as the reaction of the absolute ideal native mind against the dependence in which the empirical reception of impressions from without, and their reproduction in conceptions, place it. In this process, it does not only fashion in itself the phenomenal world, but it rather fashions out of itself a world which is all its own.