One kind of categorial change, however, is excluded from the manifest image by stipulation: the addition to the framework of new concepts of basic objects by means of theoretical postulation.  This is the move Sellars stipulates to be definitive of the scientific image.  Science, by postulating new kinds of basic entities (e.g., subatomic particles, fields, collapsing packets of probability waves), slowly constructs a new framework that claims to be a complete description and explanation of the world and its processes. The scientific image grows out of and is methodologically posterior to the manifest image, which provides the initial framework in which science is nurtured, but Sellars claims that “the scientific image presents itself as a rival image.  From its point of view the manifest image on which it rests is an ‘inadequate’ but pragmatically useful likeness of a reality which first finds its adequate (in principle) likeness in the scientific image” (PSIM, in SPR: 20; in ISR: 388). 