L.wittgenstein on certainty (uber gewissheit)

Ludwig Wittgenstein

On Certainty
(Uber Gewissheit)

ed. G.E.M.Anscombe and G.H.von Wright

Translated by Denis Paul and G.E.M.Anscombe

Basil Blackwell, Oxford 1969–1975

Preface

What we publish here belongs to the last year and a half of Wittgenstein’s life. In the middle of 1949 he visited the United States at the invitation of Norman Malcolm, staying at Malcolm’s house inIthaca. Malcolm acted as a goad to his interest in Moore’s ‘defence of common sense’, that is to say his claim to know a number of propositions for sure, such as “Here is one hand, and here is another”, and “The earth existed for a long time before my birth”, and “I have never been far from the earth’s surface”. The first of these comes in Moore’s ‘Proof of the External World’. The two others are inhis ‘Defence of Common Sense’; Wittgenstein had long been interested in these and had said to Moore that this was his best article. Moore had agreed. This book contains the whole of what Wittgenstein wrote on this topic from that time until his death. It is all first–draft material, which he did not live to excerpt and polish. The material falls into four parts; we have shown the divisions at #65,#192, #299. What we believe to be the first part was written on twenty loose sheets of lined foolscap, undated. These Wittgenstein left in his room in G.E.M.Anscombe’s house in Oxford, where he lived (apart from a visit to Norway in the autumn) from April 1950 to February 1951. I (G.E.M.A.) am under the impression that he had written them in Vienna, where he stayed from the previous Christmas untilMarch; but I cannot now recall the basis of this impression. The rest is in small notebooks, containing dates; towards the end, indeed, the date of writing is always given. The last entry is two days before his death on April 29th 1951. We have left the dates exactly as they appear in the manuscripts. The numbering of the single sections, however, is by the Editors.

It seemed appropriate topublish this work by itself. It is not a selection; Wittgenstein marked it off in his notebooks as a separate topic, which he apparently took up at four separate periods during this eighteen months. It constitutes a single sustained treatment of the topic. G.E.M. Anscombe G.H. von Wright

1. If you do know that here is one hand, we’ll grant you all the rest. When one says that such and such aproposition can’t be proved, of course that does not mean that it can’t be derived from other propositions; any proposition can be derived from other ones. But they may be no more certain than it is itself. (On this a curious remark by H.Newman.) 2. From its seeming to me – or to everyone – to be so, it doesn’t follow that it is so. What we can ask is whether it can make sense to doubt it. 3. Ife.g. someone says “I don’t know if there’s a hand here” he might be told “Look closer”. – This possibility of satisfying oneself is part of the language–game. Is one of its essential features. 4. “I know that I am a human being.” In order to see how unclear the sense of this proposition is, consider its negation. At most it might be taken to mean “I know I have the organs of a human”. (E.g. a brainwhich, after all, no one has ever yet seen.) But what about such a proposition as “I know I have a brain”? Can I doubt it? Grounds for doubt are lacking! Everything speaks in its favour, nothing against it. Nevertheless it is imaginable that my skull should turn out empty when it was operated on. 5. Whether a proposition can turn out false after all depends on what I make count as determinants forthat proposition. 6. Now, can one enumerate what one knows (like Moore)? Straight off like that, I believe not. – For otherwise the expression “I know” gets misused. And through this misuse a queer and extremely important mental state seems to be revealed. 7. My life shows that I know or am certain that there is a chair over there, or a door, and so on. – I tell a friend e.g. “Take that chair...