 Among the many kinds of beings Wyclif lists, the most important set is that consisting of categorial beings. They are characterized by the double fact of having a nature and of being the constitutive elements of finite corporeal beings or atomic states of affairs. These categorial items, conceived of as instances of a certain kind of being, are called by Wyclif ‘essences’ (essentiae). An essence therefore is a being that has a well defined nature, even if the name ‘essence’ does not make this nature known (De ente primo in communi, chap. 3, pp. 88–89; De ente praedicamentali, chap. 5, p. 43; Tractatus de universalibus, chap. 7, pp. 128–29; De materia et forma, chap. 4, pp. 185–86). So the term ‘essence’ (essentia) is less general than ‘being’ (ens), but more general than ‘quiddity’ (quidditas), since (i) every essence is a being, and not every being is an essence, and (ii) every quiddity is an essence, and not every essence is a quiddity, as individual things are essences but are not quiddities (see Kenny 1985, pp. 21 ff.; and Conti 1993, pp. 171–81).