In this week’s reading “Certainty” by Moore, Moore touches on many philosophy questions, such as the nature of dreams, certainty, and sensory perception. I would like to comment on the points of his argument where he claims that an opposite claim from his is no better than his claim. For example, he claims that his argument “I know that I am standing up, and therefore I know that I am not dreaming” and “You don’t know that you are not dreaming, and therefore don’t know that you are standing up” are equally valid claims (Moore 364).It seems that only one of the two claims can be true, since Moore can either know or not know that he is standing, and Moore can be dreaming or not dreaming. The binomial statuses of standing, dreaming, and knowing ensure that these two claims are mutually exclusive. Moore’s argument can be written like this
- If I don’t know that I am not dreaming, then I don’t know that I am standing up.
- I know that I am standing up.
- .: I know that I am not dreaming.
While this is formally valid argument Moore does not discuss how he know that he is standing up. Since this is not discussed he is unable to create the sort of “certainty” that the article suggests.
I feel that the lack of certainty and doubt about these claims touches on a point similar to one that Descartes raised “there may be reasons which are strong enough to compel us to doubt, even though these reasons are themselves doubtful, and hence are not to be retained later on” (Oeuvres de Descartes, Adam, Charles, and Paul Tannery, (eds.) 1904. Paris: J. Vrin 7:473–74). If a skeptical argument relies on the universality of doubt and the doubt itself is doubtful, then the original arguments have little foundation to rely on. If you have reasons to believe a claim, such as “I am standing”, but only doubtful reasons to believe the contrary, then perhaps it make sense to believe the original claim despite the lack of “certainty”. Unless we can create a certain universal rule on how we can acquire knowledge, we will have a hard time disproving a skeptical hypothesis, since we may be simply deceived in what we actually know.
Also the conclusion of this claim seems to go against intuition. The first claim makes “knowing that he is standing” and “knowing that he is dreaming” mutually exclusive. However this doesn’t seem to always be the case. Moore discusses a situation in which a duke dreamt that he was standing up talking in the house of lords, and then woke up and was talking in the house of lords (Moore 362). In this situation, the duke is both standing up and dreaming. If this Duke were then given all the knowledge of his situation by any means whether it is divine intervention or deep contemplation, would it not follow that he would both know that “he is standing” and that “he is dreaming”? Why then is Moore’s knowledge that he is standing strong enough to cause entailment in his claim “I know that I am standing up, and therefore I know that I am not dreaming”?