 In more detail, Suárez offers six distinct worries about final causation (DM XXIII 1.1–6): (i) Every cause is a principium, but no end is a principium; hence, no end is a cause of any kind; (ii) every cause infuses being (influit esse) into its effect; no end does so; hence, no end is a cause: (iii) a form is an end; if an end were a real cause, form would thus have to cause itself; nothing causes itself; hence the end is not a real cause; (iv) if an end is real cause, then it is also a moving principle, and no end is a moving principle; hence, no end is a cause; (v) natural agents (here Suárez is thinking of elements and beasts) have determinate propensities; the postulation of ends for beings with determinate propensities is idle; hence, the postulation of final causes for natural agents lacks sufficient foundation; (vi) one cannot specify what or in relation to what (quid vel circa quid) a final cause causes; if not, then a final cause does not impart motion; hence, a final cause is not a cause.