 The Theravāda Abhidhamma sets out its theory of the consciousness process (citta-vīthi) in its commentaries and manuals, mainly in the works of Buddhaghosa, Buddhadatta (5th century CE), and Anuruddha (10th or 11th century CE), based on earlier descriptions in the Dhammasaṅgaṇi and the Paṭṭhāna (Vism XIV 111–124, XVII 126–145; Dhs-a 82–106 &amp; 267–287; Vibh-a 155–160; Abhidh-s 17–21). The theory is not separate from the dhamma taxonomy and the analysis of citta as previously outlined in section 2. Rather, in congruency with the notion of existence (whether categorial or ontological) as functioning, it analyzes sensory perception as resulting from particular functions that are performed by the eighty-nine citta types revealed by the foregoing taxonomy. According to this analysis, the specific functions in the consciousness flow occur at particular instants of that continuum, as the normal flow of consciousness involves the mind picking up and putting down sense objects by means of successive sets of associated mental factors. The result is a fairly static account of mental and material phenomena as they arise in consciousness over a series of consciousness  moments.[16]