9 ideas
21563 | The 'no classes' theory says the propositions just refer to the members [Russell] |
Full Idea: The contention of the 'no classes' theory is that all significant propositions concerning classes can be regarded as propositions about all or some of their members. | |
From: Bertrand Russell (On 'Insolubilia' and their solution [1906], p.200) | |
A reaction: Apparently this theory has not found favour with later generations of theorists. I see it in terms of Russell trying to get ontology down to the minimum, in the spirit of Goodman and Quine. |
21565 | Richard's puzzle uses the notion of 'definition' - but that cannot be defined [Russell] |
Full Idea: In Richard's puzzle, we use the notion of 'definition', and this, oddly enough, is not definable, and is indeed not a definite notion at all. | |
From: Bertrand Russell (On 'Insolubilia' and their solution [1906], p.209) | |
A reaction: The background for this claim is his type theory, which renders certain forms of circular reference meaningless. |
21564 | Vicious Circle: what involves ALL must not be one of those ALL [Russell] |
Full Idea: The 'vicious-circle principle' says 'whatever involves an apparent variable must not be among the possible values of that variable', or (less exactly) 'whatever involves ALL must not be one of ALL which it involves. | |
From: Bertrand Russell (On 'Insolubilia' and their solution [1906], p.204) | |
A reaction: He offers this as a parallel to his 'no classes' principle. That referred to classes, but this refers to propositions, and specifically the Liar Paradox (which he calls the 'Epimenedes'). |
19553 | Commitment to 'I have a hand' only makes sense in a context where it has been doubted [Hawthorne] |
Full Idea: If I utter 'I know I have a hand' then I can only be reckoned a cooperative conversant by my interlocutors on the assumption that there was a real question as to whether I have a hand. | |
From: John Hawthorne (The Case for Closure [2005], 2) | |
A reaction: This seems to point to the contextualist approach to global scepticism, which concerns whether we are setting the bar high or low for 'knowledge'. |
19551 | How can we know the heavyweight implications of normal knowledge? Must we distort 'knowledge'? [Hawthorne] |
Full Idea: Those who deny skepticism but accept closure will have to explain how we know the various 'heavyweight' skeptical hypotheses to be false. Do we then twist the concept of knowledge to fit the twin desiderata of closue and anti-skepticism? | |
From: John Hawthorne (The Case for Closure [2005], Intro) | |
A reaction: [He is giving Dretske's view; Dretske says we do twist knowledge] Thus if I remember yesterday, that has the heavyweight implication that the past is real. Hawthorne nicely summarises why closure produces a philosophical problem. |
19552 | We wouldn't know the logical implications of our knowledge if small risks added up to big risks [Hawthorne] |
Full Idea: Maybe one cannot know the logical consequences of the proposition that one knows, on account of the fact that small risks add up to big risks. | |
From: John Hawthorne (The Case for Closure [2005], 1) | |
A reaction: The idea of closure is that the new knowledge has the certainty of logic, and each step is accepted. An array of receding propositions can lose reliability, but that shouldn't apply to logic implications. Assuming monotonic logic, of course. |
19554 | Denying closure is denying we know P when we know P and Q, which is absurd in simple cases [Hawthorne] |
Full Idea: How could we know that P and Q but not be in a position to know that P (as deniers of closure must say)? If my glass is full of wine, we know 'g is full of wine, and not full of non-wine'. How can we deny that we know it is not full of non-wine? | |
From: John Hawthorne (The Case for Closure [2005], 2) | |
A reaction: Hawthorne merely raises this doubt. Dretske is concerned with heavyweight implications, but how do you accept lightweight implications like this one, and then suddenly reject them when they become too heavy? [see p.49] |
20890 | Why do sexual relationships need permanence, if other relationships don't? [Punzo] |
Full Idea: What is the reason for demanding permanence in the relationship of sexual partners when we do not see such permanence as being importance to other human relationships? | |
From: Vincent C. Punzo (Morality and Human Sexuality [1969], p.220) | |
A reaction: The distinction may not be that simple. 'Loyalty' must certainly be mentioned. Friends can legitimately drift apart, but to desert a close friend at a time of great need might be as great a crime as adultery. When is loyalty particularly needed? |
20891 | Does engaging in sexual intercourse really need no more thought than playing tennis? [Punzo] |
Full Idea: It seems strange for a man and a woman to give no more thought to the question of whether they should engage in sexual intercourse than to the question of whether they shoud play tennis. | |
From: Vincent C. Punzo (Morality and Human Sexuality [1969], p.221) | |
A reaction: This strikes me as a reasonable point, but times have moved on since 1969, and for plenty of people nowadays playing tennis is a bigger issue than having sex, because of the time, equipment and effort involved. |