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.