divisibility, transience, change). As such, it is spiritual, eternal and, in and through its own non-sensual content, and not through shifting and imperfect determinations, completely determined or completely real. Boström claims Plato as the source of these metaphysical presuppositions. Boström interprets Plato as having conceived a limited precursor of his own philosophy, constricted by his Paganism. In Plato, the ideas constitute the absolute, whereas Boström stresses the need to move beyond the ideas to that being whose sensations they are. Boström takes himself to show that all spiritual reality necessarily refers to self-consciousness as its principle, and he maintains that true reality is personal and hence that philosophy is the science of personal beings as such, since some such thing as pure self-consciousness only exists in the abstract, whereas everything real is individual or fully determined self-consciousness (consciousness of something), or in other words, sensational being or person. Philosophy can deal with an impressional reality only insofar as this reality is conceived as a determination (sensation) for a personal being and is explained through it. With respect to the various ways in which these beings are conceived as existing for men and determining their activities, Boström divides philosophy into theoretical philosophy, the science of these beings conceived as determining man's theoretical faculty, i.e., conceived as in every respect true and original being; and practical philosophy, the science of these beings conceived as determining the practical faculty, or will, of man, i.e., conceived as that which unconditionally and under all circumstances ought to be. According to the different kinds of personal beings that are known to us, theoretical philosophy is further divided into speculative theology, speculative ethnology and speculative anthropology; practical philosophy into philosophy of religion, philosophy of law and ethics, corresponding to the terms of the division of theoretical philosophy Theoretical philosophy Speculative theology In speculative theology, the science of the absolute person, or God, Boström gives a more detailed justification of the principle of his system. There, it is first of all maintained that independent reality necessarily must be spiritual (or, as we would say today, mental), and as such an independent consciousness or self-consciousness. This is the only thing that is simple. Since the complex presupposes the simple, self-consciousness must also be the ultimate principle of all reality. This self-consciousness — which Boström identifies with life—can thus not be conceived as attached to a substrate or a substance,