 The appeal to tradition (oral instruction) is necessary, Mendelssohn adds, given the fact that, over the course of time, the laws themselves become unintelligible “since no words or letters retain their sense unchanged from one generation to the next” (Jerusalem (1983), p. 128 (translation slightly altered)/Gesammelte Schriften 8, p. 193). In chapter 1 of Jerusalem he makes a similar claim after noting (a) the elusiveness of inner perceptions to the perceiver herself and (b) the impossibility of two people using the same words to express the same “inner perceptions” (Jerusalem (1983), p. 66/Gesammelte Schriften 8, pp. 133f). Where the words in question designate inner perceptions, there is no possibility of ostensive definition, no more when uttered today than when uttered ages ago. Indeed, in a passage that suggests both the inscrutability and endless deferral of reference, Mendelssohn observes that “words cannot be explained [erläutert] by things. Instead, we must again have recourse to signs and words and, ultimately, to metaphors” (Jerusalem (1983), p. 66/Gesammelte Schriften 8, pp. 133f). Nonetheless, Mendelssohn is more confident about words designating objects of external perceptions and about the prospects for mutual understanding in regard to them. Not incidentally, ceremonial law’s ritualized character calls for a recurrent context (including specific objects and persons) available to external perception in the course of an exchange between persons (including God). Notably, ‘you’ and ‘we’ take precedence over ‘I’ and ‘it’ in such contexts, as the living references of the former indexicals enables one to refer effectively to oneself and to things generally.