Sheffer stroke also called alternative denial, a binary truth-functor represented by the symbol ‘_’, the logical force of which can be expressed contextually in terms of ‘-‘ and ‘&’ by the following definition: p_q % Df -(p & q). The importance of the Sheffer stroke lies in the fact that it by itself can express any well-formed expression of truth-functional logic. Thus, since {-,7} forms an expressively complete set, defining -p as p_p and p 7 q as (p_p) _(q_q) provides for the possibility of a further reduction of primitive functors to one. This system of symbols is commonly called the stroke notation. I.Bo. shen, Chinese term meaning ‘spirit’, ‘spiritual’, ‘numinous’, ‘demonic’. In early texts, shen is used to mean various nature spirits, with emphasis on the efficacy of spirits to both know and accomplish (hence one seeks their advice and aid). Shen came to describe the operations of nature, which accomplishes its ends with ‘spiritual’ efficacy. In texts like the Chuang Tzu, Hsün Tzu, and I-Ching, shen no longer refers to an entity but to a state of resonance with the cosmos. In such a state, the sage can tap into the ‘spiritual’ nature of an event, situation, person, or text and successfully read, react to, and guide the course of events. P.J.I.