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 which man has not yet attained knowledge. Scientific research is the endeavor to increase knowledge, and its methods are experience, observation and verification. Fallacies are erroneous inferences in relation to known things. All certitudes are described in terms of number, space, motion, time and judgment; nothing else has yet been discovered and nothing else can be discovered with the faculties with which man is possessed.

In the material world we have no knowledge of something which is not a unity of itself or a unity of a plurality; of something which is not an extension of figure or an extension of figure and structure; of something which has not motion or a combination of motions as force; of something which has not duration as persistence or duration with persistence and change.

In the mental world we have no knowledge of something which is not a judgment of consciousness and inference; of a judgment which is not a judgment of a body with number, space, motion and time. Every notion of something in the material world devoid of one or more of the constituents of matter is an illusion; every notion of something in the spiritual world devoid of the factors of matter and judgment is a fallacy. These are the propositions to be explained and demonstrated.

In the following chapters an attempt will be made to show that we know much about matter, and although we do not know all, all we know is about matter in its essentials of number, space, motion, time and judgment, or that we know of matter in its four essentials and of mind as consciousness exhibited in judgment and concepts, but always this mind