6 ideas
20768 | Like spiderswebs, dialectical arguments are clever but useless [Ariston, by Diog. Laertius] |
Full Idea: He said that dialectical arguments were like spiderswebs: although they seem to indicate craftsmanlike skill, they are useless. | |
From: report of Ariston (fragments/reports [c.250 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 07.161 | |
A reaction: Useful for the spider, but useless to Ariston. |
13342 | Carnap defined consequence by contradiction, but this is unintuitive and changes with substitution [Tarski on Carnap] |
Full Idea: Carnap proposed to define consequence as 'sentence X follows from the sentences K iff the sentences K and the negation of X are contradictory', but 1) this is intuitively impossible, and 2) consequence would be changed by substituting objects. | |
From: comment on Rudolph Carnap (The Logical Syntax of Language [1934], p.88-) by Alfred Tarski - The Concept of Logical Consequence p.414 | |
A reaction: This seems to be the first step in the ongoing explicit discussion of the nature of logical consequence, which is now seen by many as the central concept of logic. Tarski brings his new tool of 'satisfaction' to bear. |
13251 | Each person is free to build their own logic, just by specifying a syntax [Carnap] |
Full Idea: In logic, there are no morals. Everyone is at liberty to build his own logic, i.e. his own form of language. All that is required is that he must state his methods clearly, and give syntactical rules instead of philosophical arguments. | |
From: Rudolph Carnap (The Logical Syntax of Language [1934], §17), quoted by JC Beall / G Restall - Logical Pluralism 7.3 | |
A reaction: This is understandable, but strikes me as close to daft relativism. If I specify a silly logic, I presume its silliness will be obvious. By what criteria? I say the world dictates the true logic, but this is a minority view. |
16362 | An identity statement aims at getting the hearer to merge two mental files [Lockwood] |
Full Idea: The purpose of an identity statement is to get the hearer to merge these files or bodies of information into one. | |
From: Michael Lockwood (Identity and Reference [1971], p.209), quoted by François Recanati - Mental Files 4.1 | |
A reaction: Lockwood is a pioneer, in seeing 'Hesperus is Phosphorus' and 'Scott is the author of 'Waverley'' in terms of how the mind works. Mental files seem to me to explain a huge amount. Recanati proposes 'linking' rather than 'merging'. |
3049 | The chief good is indifference to what lies midway between virtue and vice [Ariston, by Diog. Laertius] |
Full Idea: The chief good is to live in perfect indifference to all those things which are of an intermediate character between virtue and vice. | |
From: report of Ariston (fragments/reports [c.250 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 07.2.1 |
3549 | Ariston says rules are useless for the virtuous and the non-virtuous [Ariston, by Annas] |
Full Idea: Ariston says that rules are useless if you are virtuous, and useless if you are not. | |
From: report of Ariston (fragments/reports [c.250 BCE]) by Julia Annas - The Morality of Happiness 2.4 |