When we get to this point, is the movement of knowledge completed? Our answer is: it is and yet it is not. When men in society throw themselves into the practice of changing a certain definite objective process (whether natural or social) at a certain definite stage of its development, they can, as a result of the reflection of the objective process in their brains and the exercise of their subjective activity, advance ideas, theories, plans, or programmes which correspond in general to the laws of that objective process. They then apply these ideas, theories, plans, or programmes in practice in the same objective process. And if they can realize the aims they have in mind, that is, if in that same process of practice they can translate, or on the whole translate, those previously formulated ideas, theories, plans, or programmes into fact, then the movement of knowledge may be considered completed with regard to that particular process. In the [p. 231] process of changing nature, take for example the fulfillment of an engineering plan, the verification of a scientific hypothesis, the manufacture of an implement, or the reaping of a crop; or in the process of changing society, take for example the victory of a strike, victory in a war, the fulfillment of an educational plan, the establishment of an organization to save the nation. All these may be considered the realization of aims one has in mind. But generally, whether in the practice of changing nature or of changing society, men’s original ideas, theories, plans, or programmes are seldom realized without any alteration. This is because people engaged in changing reality are usually subject to numerous limitations; they are limited not only by existing scientific and technological conditions but also by[3-353] the degree to which the objective process has become manifest (the aspect and the essence of the objective process have not yet been fully revealed). In such a situation, ideas, theories, plans, or programmes are usually altered partially and sometimes even wholly, because of the discovery of unforeseen circumstances in the course of practice. That is to say, it does happen that the original ideas, theories,[3-354] plans, or programmes fail to correspond with reality either in whole or in part and are wholly or partially incorrect. In many instances, failures have to be repeated many times before errors in knowledge can be corrected and correspondence with the laws of the objective process achieved, and consequently before the subjective can be transformed into correct knowledge of the objective (or in other words, before the anticipated results can be achieved in practice).[3-355] But when that point is reached, no matter how, the movement of human knowledge regarding a certain definite objective process at a certain definite stage of its development may be considered completed.