11 ideas
10429 | It is best to say that a name designates iff there is something for it to designate [Sainsbury] |
Full Idea: It is better to say that 'For all x ("Hesperus" stands for x iff x = Hesperus)', than to say '"Hesperus" stands for Hesperus', since then the expression can be a name with no bearer (e.g. "Vulcan"). | |
From: Mark Sainsbury (The Essence of Reference [2006], 18.2) | |
A reaction: In cases where it is unclear whether the name actually designates something, it seems desirable that the name is at least allowed to function semantically. |
10425 | Definite descriptions may not be referring expressions, since they can fail to refer [Sainsbury] |
Full Idea: Almost everyone agrees that intelligible definite descriptions may lack a referent; this has historically been a reason for not counting them among referring expressions. | |
From: Mark Sainsbury (The Essence of Reference [2006], 18.2) | |
A reaction: One might compare indexicals such as 'I', which may be incapable of failing to refer when spoken. However 'look at that!' frequently fails to communicate reference. |
10438 | Definite descriptions are usually rigid in subject, but not in predicate, position [Sainsbury] |
Full Idea: Definite descriptions used with referential intentions (usually in subject position) are normally rigid, ..but in predicate position they are normally not rigid, because there is no referential intention. | |
From: Mark Sainsbury (The Essence of Reference [2006], 18.5) | |
A reaction: 'The man in the blue suit is the President' seems to fit, but 'The President is the head of state' doesn't. Seems roughly right, but language is always too complex for philosophers. |
7557 | To solve Zeno's paradox, reject the axiom that the whole has more terms than the parts [Russell] |
Full Idea: Presumably Zeno appealed to the axiom that the whole has more terms than the parts; so if Achilles were to overtake the tortoise, he would have been in more places than the tortoise, which he can't be; but the conclusion is absurd, so reject the axiom. | |
From: Bertrand Russell (Mathematics and the Metaphysicians [1901], p.89) | |
A reaction: The point is that the axiom is normally acceptable (a statue contains more particles than the arm of the statue), but it breaks down when discussing infinity (Idea 7556). Modern theories of infinity are needed to solve Zeno's Paradoxes. |
10059 | In mathematic we are ignorant of both subject-matter and truth [Russell] |
Full Idea: Mathematics may be defined as the subject in which we never know what we are talking about, nor whether what we are saying is true. | |
From: Bertrand Russell (Mathematics and the Metaphysicians [1901], p.76) | |
A reaction: A famous remark, though Musgrave is rather disparaging about Russell's underlying reasoning here. |
7556 | A collection is infinite if you can remove some terms without diminishing its number [Russell] |
Full Idea: A collection of terms is infinite if it contains as parts other collections which have as many terms as it has; that is, you can take away some terms of the collection without diminishing its number; there are as many even numbers as numbers all together. | |
From: Bertrand Russell (Mathematics and the Metaphysicians [1901], p.86) | |
A reaction: He cites Dedekind and Cantor as source for these ideas. If it won't obey the rule that subtraction makes it smaller, then it clearly isn't a number, and really it should be banned from all mathematics. |
7554 | Self-evidence is often a mere will-o'-the-wisp [Russell] |
Full Idea: Self-evidence is often a mere will-o'-the-wisp, which is sure to lead us astray if we take it as our guide. | |
From: Bertrand Russell (Mathematics and the Metaphysicians [1901], p.78) | |
A reaction: The sort of nice crisp remark you would expect from a good empiricist philosopher. Compare Idea 4948. However Russell qualifies it with the word 'often', and all philosophers eventually realise that you have to start somewhere. |
10432 | A new usage of a name could arise from a mistaken baptism of nothing [Sainsbury] |
Full Idea: A baptism which, perhaps through some radical mistake, is the baptism of nothing, is as good a propagator of a new use as a baptism of an object. | |
From: Mark Sainsbury (The Essence of Reference [2006], 18.3) | |
A reaction: An obvious example might be the Loch Ness Monster. There is something intuitively wrong about saying that physical objects are actually part of linguistic meaning or reference. I am not a meaning! |
10434 | Even a quantifier like 'someone' can be used referentially [Sainsbury] |
Full Idea: A large range of expressions can be used with referential intentions, including quantifier phrases (as in 'someone has once again failed to close the door properly'). | |
From: Mark Sainsbury (The Essence of Reference [2006], 18.5) | |
A reaction: This is the pragmatic aspect of reference, where it can be achieved by all sorts of means. But are quantifiers inherently referential in their semantic function? Some of each, it seems. |
10431 | Things are thought to have a function, even when they can't perform them [Sainsbury] |
Full Idea: On one common use of the notion of a function, something can possess a function which it does not, or even cannot, perform. A malformed heart is to pump blood, even if such a heart cannot in fact pump blood. | |
From: Mark Sainsbury (The Essence of Reference [2006], 18.2) | |
A reaction: One might say that the heart in a dead body had the function of pumping blood, but does it still have that function? Do I have the function of breaking the world 100 metres record, even though I can't quite manage it? Not that simple. |
9425 | Lewis later proposed the axioms at the intersection of the best theories (which may be few) [Mumford on Lewis] |
Full Idea: Later Lewis said we must choose between the intersection of the axioms of the tied best systems. He chose for laws the axioms that are in all the tied systems (but then there may be few or no axioms in the intersection). | |
From: comment on David Lewis (Subjectivist's Guide to Objective Chance [1980], p.124) by Stephen Mumford - Laws in Nature |