6 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'). |
5959 | Some philosophers say the soul is light [Plutarch] |
Full Idea: Some philosophers hold that the soul is in its essence light. | |
From: Plutarch (75: Is 'Live Unknown' a Wise Precept? [c.85], §6) | |
A reaction: A nice idea, to rival the stoic view that the soul is fire. It is understandable to propose that the soul is some sort of lightweight and fast moving matter. How else could thought be achieved physically? Nowadays, parallel processing is our only model. |
13304 | Learned men gain more in one day than others do in a lifetime [Posidonius] |
Full Idea: In a single day there lies open to men of learning more than there ever does to the unenlightened in the longest of lifetimes. | |
From: Posidonius (fragments/reports [c.95 BCE]), quoted by Seneca the Younger - Letters from a Stoic 078 | |
A reaction: These remarks endorsing the infinite superiority of the educated to the uneducated seem to have been popular in late antiquity. It tends to be the religions which discourage great learning, especially in their emphasis on a single book. |
20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |
Full Idea: Posidonius defined time thus: it is an interval of motion, or the measure of speed and slowness. | |
From: report of Posidonius (fragments/reports [c.95 BCE]) by John Stobaeus - Anthology 1.08.42 | |
A reaction: Hm. Can we define motion or speed without alluding to time? Looks like we have to define them as a conjoined pair, which means we cannot fully understand either of them. |