Let us follow the initial steps of Kant's analysis. Mind and Universe--Subject and Object--Ego and Non-ego, stand opposite one another, front to front. Mind is conscious only of its own operations: the subject alone considers. The first fact noted is, that the subject is sensitive to impressions made by outward things, and is receptive of them. Dwelling on this fact, we discover that while the impressions are many in number and of great variety, they all, whatever their character, fall within certain inflexible and unalterable conditions--those of space and time--which must, therefore, be regarded as pre-established forms of sensibility. "Time is no empirical conception which can be deduced from experience. Time is a necessary representation which lies at the foundation of all intuitions. Time is given à priori. In it alone is any reality of phenomena possible. These disappear, but it cannot be annihilated." So of space. "Space is an intuition, met with in us à priori, antecedent to any perception of objects, a pure, not an empirical intuition." These two forms of sensibility, inherent and invariable, to which all experiences are subject, are primeval facts of consciousness. Kant's argument on the point whether or no space and time have an existence apart from the mind, is interesting, but need not detain us. The materials furnished by sensibility are taken up by the understanding, which classifies, interprets, judges, compares, reduces to unity, eliminates, converts, and thus fashions sensations into conceptions, transmutes impressions into thoughts. Here fresh processes of analysis are employed in classifying judgments, and determining their conditions. All judgments, it is found, must conform to one of four invariable conditions. I. Quantity, which may be subdivided into unity, plurality, and totality: the one, the many, the whole. II. Quality, which is divisible as reality, negation, and limitation: something, nothing, and the more or less. III. Relation, which also comprises three heads: substance and accident, cause and effect, reciprocity, or action and reaction. IV. Modality, which embraces the possible and the impossible, the existent and the non-existent, the necessary and the contingent. These categories, as they were called, after the terminology of Aristotle, were supposed to exhaust the forms of conception.