On the implausibility of slow-switching arguments in establishing incompatibility thesis



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Tartu Ülikool


Philosophers who argue that content externalism is incompatible with authoritative self-knowledge usually employ one of the two arguments namely the slow-switching argument and the reductio ad absurdum. Of these I focus on only the former which in itself has two variants namely the content-switch (main argument) and the memory argument (a variant). I argue against both the variants thereby denying that slow-switching arguments succeed in establishing the incompatibility thesis. It is long held that if a slow-switched agent (Oscar) were to stay long enough on twin earth, his thought contents change unbeknownst to him. And it was reasoned that, since Oscar is unaware of the changes in his mental contents and cannot spot when the changes occurred, he does not have access to his own thought contents at all times, which thereby leads to the conclusion that authoritative self-knowledge is incompatible with externalism. In this thesis, I argue that, in cases like these, mental contents do not change unknown to Oscar. I appeal to theories of concept acquisition to achieve this end. This forms my attack on the main argument. And, as against the memory argument, I use two strategies the first one of which is an extension of the previous argument applied to this case; and the second strategy is to argue that memorial recollection depends on the past, and not the present, environment and, if Oscar does not forget any relevant past stimuli, his memorial contents upon recollection will not change. Having thus argued against both the variants of the slow-switching arguments, I conclude that slow-switching arguments do not succeed in establishing the incompatibility thesis.