11 ideas
| 15527 | Defining terms either enables elimination, or shows that they don't require elimination [Lewis] |
| Full Idea: To define theoretical terms might be to show how to do without them, but it is better to say that it shows there is no good reason to want to do without them. | |
| From: David Lewis (How to Define Theoretical Terms [1970], Intro) |
| 15530 | A logically determinate name names the same thing in every possible world [Lewis] |
| Full Idea: A logically determinate name is one which names the same thing in every possible world. | |
| From: David Lewis (How to Define Theoretical Terms [1970], III) | |
| A reaction: This appears to be rigid designation, before Kripke introduced the new word. |
| 15528 | A Ramsey sentence just asserts that a theory can be realised, without saying by what [Lewis] |
| Full Idea: If we specify a theory with all of its terms, and then replace all of those terms with variables, we can then say that some n-tuples of entities can satisfy this formula. This Ramsey sentence then says the theory is realised, without specifying by what. | |
| From: David Lewis (How to Define Theoretical Terms [1970], II) | |
| A reaction: [I have compressed Lewis, and cut out the symbolism] |
| 15526 | There is a method for defining new scientific terms just using the terms we already understand [Lewis] |
| Full Idea: I contend that there is a general method for defining newly introduced terms in a scientific theory, one which uses only the old terms we understood beforehand. | |
| From: David Lewis (How to Define Theoretical Terms [1970], Intro) | |
| A reaction: Lewis is game is to provide bridge laws for a reductive account of nature, without having to introduce something entirely new to achieve it. The idea of bridge laws in scientific theory is less in favour these days. |
| 15529 | It is better to have one realisation of a theory than many - but it may not always be possible [Lewis] |
| Full Idea: A uniquely realised theory is, other things being equal, certainly more satisfactory than a multiply realised theory. We should insist on unique realisation as a standard of correctness unless it is a standard too high to be met. | |
| From: David Lewis (How to Define Theoretical Terms [1970], III) | |
| A reaction: The point is that rewriting a theory as Ramsey sentences just says there is at least one realisation, and so it doesn't meet the highest standards for scientific theories. The influence of set-theoretic model theory is obvious in this approach. |
| 15531 | The Ramsey sentence of a theory says that it has at least one realisation [Lewis] |
| Full Idea: The Ramsey sentence of a theory says that it has at least one realisation. | |
| From: David Lewis (How to Define Theoretical Terms [1970], V) |
| 21375 | Reason can be vicious, and great crimes have to be rational [Schopenhauer] |
| Full Idea: Reasonable and vicious are quite consistent with each other, in fact, only through their union are great and far-reaching crimes possible. | |
| From: Arthur Schopenhauer (On the Basis of Morality [1841], p.83), quoted by Christopher Janaway - Schopenhauer 7 'Against' | |
| A reaction: This is opposed to Kant, who always looks wildly optimistic in his hope that high rationality entails a morally good will. Good people seem to have a fairly irrational empathy with their fellow citizens. |
| 21379 | Man's three basic ethical incentives are egoism, malice and compassion [Schopenhauer] |
| Full Idea: Man's three fundamental ethical incentives, egoism, malice and compassion, are present in everyone in different and incredibly unequal proportions. In accordance with them, motives will operate on man and actions will ensue. | |
| From: Arthur Schopenhauer (On the Basis of Morality [1841], p.192), quoted by Christopher Janaway - Schopenhauer 7 'Egoism' | |
| A reaction: A well chosen trio. Kant would be shocked that he has left out duty, which is supposed to rise above such feelings. |
| 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. |
| 21376 | Philosophy treats animals as exploitable things, ignoring the significance of their lives [Schopenhauer] |
| Full Idea: In philosophical morals animals are mere 'things', mere means to any end whatsoever. ...Shame on such a morality, that fails to recognise the eternal essence that lives in every living thing, and shines forth with inscrutable significance from all eyes. | |
| From: Arthur Schopenhauer (On the Basis of Morality [1841], p.96), quoted by Christopher Janaway - Schopenhauer 7 'Against' | |
| A reaction: Good. I find Kant's theoretical indifference to animals very creepy (despite his kind attitude to them). And I also think the utilitarians are wrong to only value animals for their pain, as if any animal could be shredded for fun, if it felt no pain. |
| 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. |