On Certainty
Posted by Ali Reda | Posted in | Posted on 10/20/2013
Its starting point is Wittgenstein’s response to a paper by G. E. Moore, called “A Proof of the External World.” In this paper, Moore tries to prove that there is a world external to our senses by holding up his hand and saying “here is a hand.” Wittgenstein admires the boldness of Moore’s approach, which implicitly questions the reasonableness of doubting such a claim, but he suggests that Moore fails because his claim that he knows he has a hand automatically invites the question of how he knows. The idea of doubting the existence of a world external to our senses gains a foothold from the fact that any knowledge claim can be doubted, and every attempt at justification of a knowledge claim can also be doubted.
“If a blind man were to ask me “Have you got two hands?” I should not make sure by looking. If I were to have any doubt of it, then I don’t know why I should trust my eyes. For why shouldn't I test my eyes by looking to find out whether I see my two hands? What is to be tested by what?”
Wittgenstein does not try to refute skeptical doubts about the existence of an external world so much as he tries to sidestep them. If two people disagree over whether one of them has a hand, it is unclear whether they can agree on anything that might act as a common ground on which they can debate the matter. Communication and rational thought are only possible between people when there is some sort of common ground, and when one doubts such fundamental propositions as “here is a hand,” that common ground shrinks to nothing. Skeptical doubts purport to take place within a framework of rational debate, but by doubting too much, they undermine rationality itself, and so undermine the very basis for doubt.
“At the core of all well-founded belief lies belief that is unfounded.”According to Wittgenstein, a proposition has no meaning unless it is placed within a particular context. “Here is a hand,” by itself, means nothing, though those words might come to have meaning in the context of an anatomy class or of a parent teaching a child to speak. However, once we give propositions a particular context, the doubts cast by a skeptic lack the kind of generality that would throw the very existence of the external world into doubt. Only by removing language from all possible contexts, and hence rendering language useless, can skepticism function.
The child learns to believe a host of things. I.e. it learns to act according to these beliefs. Bit by bit there forms a system of what is believed, and in that system some things stand unshakeably fast and some are more or less liable to shift. What stands fast does so, not because it is intrinsically obvious or convincing; it is rather held fast by what lies around it.
Excellent summary, thanks.