The notion of Persistence gives way to several predominant theories; of which, attempt to account for many possible questions that arise from it. As in most cases of debate, when more than one account of such is held to be true, there will clearly be much disagreement. Two views that claim to account accurately for persistence that remain widely known are , that of an endurantist (Threeist) and that of a perdurantist (Twoist). The endurantist will hold that objects are wholly present at all times, a persistent object ?endures' over time. The conflicting view of a perdurantist claims that objects are actually composed of temporal parts, more precisely, proper temporal parts. Further, a Twoist (vs. Oneist), will say that a name most often refers to the sum of one's temporal parts, whereas a Threeist believes a name to refer to one who is wholly present during all times of its existence. The two opposing theories stated very simply, as above, give insight as to the nature of their arguments against one another. It does seem, however, that the Twoist's account of persistence gives an exceedingly useful notion in regards towards many more subjects of philosophy, as well as an explanation that accounts for much more in terms of the problems associated strictly with persistence itself.
The argument posed by VanIwagen, a Threeist, against the Twoist is known as the problem of Essential Duration; and the counterpart argument given by the Twoist is referred to as the problem of Temporary Intrinsics. VanInwagen's (modal) argument goes as follows: One could have lived longer than did in the actually world; this must be accounted for by either, one having been composed of mor ...