Description, Prescription, Communication

Three characteristics of a Description are: it is pre-existed by its object, its object is not necessarily human, and it is monological.  In contrast, a Prescription pre-exists its object, its object includes a human component, and the latter is explicitly its addressee, i. e. one who is to enact the formulation.  In other words, a Prescription, but not a Description, is explicitly a mode of Communciation.  Thus, #309 of the Investigations, in contrast with #124, is significant insofar as in it, Wittgenstein defines Philosophy as an act of Communication, i. e. he prescribes to a reader a "way out of the fly-bottle".