The only major problem I do believe may prove problematic for Geach will be the matter of parsing every ‘same as’ or ‘identical to’ relationship in order to determine what kind of identity is being invoked; it seems to me that there may be an untenable number of different types of identity that might be posited or argued for, and it may become a grave epistemological problem to attempt to index, sort, and successfully understand and deploy each type of identity correctly and for all cases in which identity is invoked. If this problem proves to be embedded in truth, at the least the Geach approach seems to provide a better starting point for the endurantist to theorize from. This problem, unlike the other major problems outlined above, does have another advantage as well; it seems that at least in this case, one can remain an empiricist and still attempt to solve this particular problem with no quirky deviations from the empiricist principle.

If one is inclined to be skeptical of Geach’s solution to Heller’s contradiction, there are still more hopes available for the endurantist. Trenton Merricks provides us with a system for erasing the problem entirely. Basically, Merricks’ seeks out a means for re-analyzing the use of referring terms in sentences that are putative cases of transtemporal identity in such a way as to allow for actual change, as well as to avoid arguments that raise problems like Heller’s (Merricks, 368-369). The heart of Merricks’ analysis is that all identity conditions are temporally bound, with a specific manner of parsing the referring term. Basically, the theory suggests that some object O that exists at one time is identical to itself existing at another time in a manner that might be similar to a bare substrate, with properties that can be attributed to O as a function of the time t that is present. The overarching goal of the Merricks theory is to enable statements pertaining to personal identity through time to be possible, even with changes in parts, traits, or properties. By the object having certain parts, properties, etc., at some present time, and not in general, the theory strips these properties from the conditions of identity. This then allows for a seemingly bare object to persist through time.

The nature of Merricks’ persistence of transtemporal identity, in being somewhat similar to the idea of bare particulars (in that the parts/properties become unnecessary for endurance/existence) lends itself to some of the same problems faced by bare particulars. It becomes difficult to envision to what extent a thing can survive change, yet still endure through time. Further, it becomes less clear as to what exactly does endure through time; something ephemeral like a soul, something material but undiscovered or indiscernible as per Chisholm’s notions, something else entirely? The aims of Merricks are certainly valuable, but it just seems that the particular deployment is unclear as it stands.

Yet another, albeit much simpler, argument against Heller’s critique is that the history of the objects in question matters. What distinguishes Descartes from Descartes(-) is simply that the two different things have two different histories at time t2, namely that Descartes underwent an amputation, whereas Descartes(-) did not. Some posit that this difference in history is enough to distinguish the two objects from eachother, but depending on how we treat the existence of Descartes and Descartes(-) before the surgery, we may not be able to parse this difference empirically. If they are spatially coincident, distinct objects, we simply cannot physically tell them apart at any time and thus cannot empirically attribute a history to either after the operation, while if Descartes(-) is simply an arbitrary undetached part of Descartes, the amputation is what would separate the two into different entities by differentiating their histories.

In the end, Heller’s argument against endurantism appears to serve to better hone distinctions between types of endurantism, and allow philosophers to select the more promising theories from the more problematic. While Heller’s original intention was to argue for perdurantist theory against endurantist theory, the problems that are inherent in perdurantist theory simply seem to grave to overcome simply, and in general it appears that Ockham’s Razor can be liberally applied to many parts of perdurantist theory. Though the argument Heller puts forward is certainly challenging for the endurantist theorists, the exercise in avoiding the logical contradiction entailed in the argument proves useful for testing the waters of mereological essentialism (including Chisholm’s prescription of it), Geach’s idea of multiple types of identity, Merricks’ notion of what I suggest is bare identity, and that history can distinguish objects. Ultimately, I endorse Geach’s take on the problem, as his view seems to be capable of both defeating Heller’s contradiction and encompbuming a number of pre-philosophical notions concerning transtemporal identity that have strong intuitive grab and provide useful mechanism for explaining how things like change are possible without negating transtemporal identity.

Citations

1. Loux, Michael. Metaphysics. Routledge, 1998.

2. Heller, Mark. “Temporal Parts of Four-Dimensional Objects.” Metaphysics: Contemporary Readings. Routledge, 1998.

3. Merricks, Trenton. “Endurance and Indiscernibility.” Metaphysics: Contemporary Readings. Routledge, 1998.