19 ideas
| 12129 | 'Truth' may only apply within a theory [Kuhn] |
| Full Idea: 'Truth' may, like 'proof', be a term with only intra-theoretic applications. | |
| From: Thomas S. Kuhn (Reflections on my Critics [1970], §5) | |
| A reaction: I think we can blame Tarski (via Quine, Kuhn's teacher) for this one. I take it to be an utter failure to grasp the meaning of the word 'truth' (and sneakily substituting 'satisfaction' for it). For a start, we have to compare theories on some basis. |
| 18767 | Free logics has terms that do not designate real things, and even empty domains [Anderson,CA] |
| Full Idea: Free logics say 1) singular terms are allowed that do not designate anything that exists; sometimes 2) is added: the domain of discourse is allowed to be empty. Logics with both conditions are called 'universally free logics'. | |
| From: C. Anthony Anderson (Identity and Existence in Logic [2014], 2.3) | |
| A reaction: I really like the sound of this, and aim to investigate it. Karel Lambert's writings are the starting point. Maybe the domain of logic is our concepts, rather than things in the world, in which case free logic sounds fine. |
| 18763 | Basic variables in second-order logic are taken to range over subsets of the individuals [Anderson,CA] |
| Full Idea: Under its now standard principal interpretation, the monadic predicate variables in second-order logic range over subsets of the domain on individuals. | |
| From: C. Anthony Anderson (Identity and Existence in Logic [2014], 1.5) | |
| A reaction: This is an interpretation in which properties are just sets of things, which is fine if you are a logician, but not if you want to talk about anything important. Still, we must play the game. Boolos introduced plural quantification at this point. |
| 18771 | Stop calling ∃ the 'existential' quantifier, read it as 'there is...', and range over all entities [Anderson,CA] |
| Full Idea: Ontological quantifiers might just as well range over all the entities needed for the semantics. ...The minimal way would be to just stop calling '∃' an 'existential quantifier', and always read it as 'there is...' rather than 'there exists...'. | |
| From: C. Anthony Anderson (Identity and Existence in Logic [2014], 2.6) | |
| A reaction: There is no right answer here, but it seems to be the strategy adopted by most logicians, and the majority of modern metaphysicians. They just allow abstracta, and even fictions, to 'exist', while not being fussy what it means. Big mistake! |
| 18769 | Do mathematicians use 'existence' differently when they say some entity exists? [Anderson,CA] |
| Full Idea: A cursory examination shows that mathematicians have no aversion to saying that this-or-that mathematical entity exists. But is this a different sense of 'existence'? | |
| From: C. Anthony Anderson (Identity and Existence in Logic [2014], 2.6) | |
| A reaction: For those of us like me and my pal Quine who say that 'exist' is univocal (i.e. only one meaning), this is a nice challenge. Quine solves it by saying maths concerns sets of objects. I, who don't like sets, am puzzled (so I turn to fictionalism...). |
| 18770 | We can distinguish 'ontological' from 'existential' commitment, for different kinds of being [Anderson,CA] |
| Full Idea: There are sensible ways to maike a distinction between different kinds of being. ..One need not fear that this leads to a 'bloated ontology'. ...We need only distinguish 'ontological commitment' from 'existential commitment' | |
| From: C. Anthony Anderson (Identity and Existence in Logic [2014], 2.6) | |
| A reaction: He speaks of giving fictional and abstract entities a 'lower score' in existence. I think he means the 'ontological' commitment to be the stronger of the two. |
| 18766 | 's is non-existent' cannot be said if 's' does not designate [Anderson,CA] |
| Full Idea: The paradox of negative existentials says that if 's' does not designate something, then the sentence 's is non-existent' is untrue. | |
| From: C. Anthony Anderson (Identity and Existence in Logic [2014], 2.1) | |
| A reaction: This only seems be a problem for logicians. Everyone else can happily say 'my coffee is non-existent'. |
| 18768 | We cannot pick out a thing and deny its existence, but we can say a concept doesn't correspond [Anderson,CA] |
| Full Idea: Parmenides was correct - one cannot speak of that which is not, even to say that it is not. But one can speak of concepts and say of them that they do not correspond to anything real. | |
| From: C. Anthony Anderson (Identity and Existence in Logic [2014], 2.5) | |
| A reaction: [This summarises Alonso Church, who was developing Frege] This sounds like the right thing to say about non-existence, but then the same principle must apply to assertions of existence, which will also be about concepts and not things. |
| 18765 | Individuation was a problem for medievals, then Leibniz, then Frege, then Wittgenstein (somewhat) [Anderson,CA] |
| Full Idea: The medieval philosophers and then Leibniz were keen on finding 'principles of individuation', and the idea appears again in Frege, to be taken up in some respects by Wittgenstein. | |
| From: C. Anthony Anderson (Identity and Existence in Logic [2014], 1.6) | |
| A reaction: I take a rather empirical approach to this supposed problem, and suggest we break 'individuation' down into its component parts, and then just drop the word. Discussions of principles of individuations strike me as muddled. Wiggins and Lowe today. |
| 18764 | The notion of 'property' is unclear for a logical version of the Identity of Indiscernibles [Anderson,CA] |
| Full Idea: In the Identity of Indiscernibles, one speaks about properties, and the notion of a property is by no means clearly fixed and formalized in modern symbolic logic. | |
| From: C. Anthony Anderson (Identity and Existence in Logic [2014], 1.5) | |
| A reaction: The unclarity of 'property' is a bee in my philosophical bonnet, in speech, and in metaphysics, as well as in logic. It may well be the central problem in our attempts to understand the world in general terms. He cites intensional logic as promising. |
| 18076 | Most theories are continually falsified [Kuhn, by Kitcher] |
| Full Idea: Kuhn contends that almost all theories are falsified at almost all times. | |
| From: report of Thomas S. Kuhn (Structure of Scientific Revolutions (2nd ed) [1962]) by Philip Kitcher - The Nature of Mathematical Knowledge 07.1 | |
| A reaction: This is obviously meant to demolish Karl Popper. |
| 22191 | Kuhn's scientists don't aim to falsifying their paradigm, because that is what they rely on [Kuhn, by Gorham] |
| Full Idea: In Kuhn's view scientists are decidedly not interested in falsifying their paradigm, because without a paradigm there is no systematic inquiry at all. | |
| From: report of Thomas S. Kuhn (Structure of Scientific Revolutions (2nd ed) [1962]) by Geoffrey Gorham - Philosophy of Science 3 | |
| A reaction: This seems to be one of the stronger aspects of Kuhn's account. You'd be leaving the big house, to go out on the road with a tent. |
| 6809 | Kuhn came to accept that all scientists agree on a particular set of values [Kuhn, by Bird] |
| Full Idea: Kuhn later came to accept that there are five values to which scientists in all paradigms adhere: accuracy; consistency with accepted theories; broad scope; simplicity; and fruitfulness. | |
| From: report of Thomas S. Kuhn (Reflections on my Critics [1970]) by Alexander Bird - Philosophy of Science Ch.8 | |
| A reaction: To shake off the relativism for which Kuhn is notorious, we should begin by asking the question WHY scientists favoured these particular values, rather than (say) bizarreness, consistency with Lewis Carroll, or alliteration. (They are epistemic virtues). |
| 22183 | Switching scientific paradigms is a conversion experience [Kuhn] |
| Full Idea: The transfer of allegiance from paradigm to paradigm is a conversion experience which cannot be forced. | |
| From: Thomas S. Kuhn (Structure of Scientific Revolutions (2nd ed) [1962]), quoted by Samir Okasha - Philosophy of Science: Very Short Intro (2nd ed) 5 | |
| A reaction: This is the controversial part of Kuhn, which says that the most important decisions are not really rational. Anyone who thought the interpretation of a bunch of evidence is logical needed their head examined. But it IS rational. |
| 6162 | Kuhn has a description theory of reference, so the reference of 'electron' changes with the descriptions [Rowlands on Kuhn] |
| Full Idea: Kuhn and Feyerabend adopt a description theory of reference; the term 'electron' refers to whatever satisfies the descriptions associated with electrons, and since these descriptions vary between theories, so too must the reference. | |
| From: comment on Thomas S. Kuhn (Structure of Scientific Revolutions (2nd ed) [1962]) by Mark Rowlands - Externalism Ch.3 | |
| A reaction: This is a key idea in modern philosophy, showing why all of reality and science were at stake when Kripke and others introduced a causal theory of reference. All the current debates about externalism and essentialism grow from this problem. |
| 22184 | Incommensurability assumes concepts get their meaning from within the theory [Kuhn, by Okasha] |
| Full Idea: The doctrine of incommensurability stems from Kuhn's belief that scientific concepts derive their meaning from the theory in which they play a role. | |
| From: report of Thomas S. Kuhn (Structure of Scientific Revolutions (2nd ed) [1962]) by Samir Okasha - Philosophy of Science: Very Short Intro (2nd ed) 5 | |
| A reaction: Quine was the source of this. Kripke's direct reference theory was meant to be the answer. |
| 7619 | Galileo's notions can't be 'incommensurable' if we can fully describe them [Putnam on Kuhn] |
| Full Idea: To tell us that Galileo had 'incommensurable' notions and then go on to describe them at length is totally incoherent. | |
| From: comment on Thomas S. Kuhn (Structure of Scientific Revolutions (2nd ed) [1962]) by Hilary Putnam - Reason, Truth and History Ch.5 | |
| A reaction: How refreshingly sensible. Incommensurability is the sort of nonsense you slide into if you take an instrumental view of science. But scientists are continually aim to pin down what is actually there. Translation between theories is very difficult! |
| 12128 | In theory change, words shift their natural reference, so the theories are incommensurable [Kuhn] |
| Full Idea: In transitions between theories words change their meanings or applicability. Though most of the signs are used before and after a revolution - force, mass, cell - the ways they attach to nature has changed. Successive theories are thus incommensurable. | |
| From: Thomas S. Kuhn (Reflections on my Critics [1970], §6) | |
| A reaction: A very nice statement of the view, from the horse's mouth. A great deal of recent philosophy has been implicitly concerned with meeting Kuhn's challenge, by providing an account of reference that doesn't have such problems. |
| 3029 | Stilpo said if Athena is a daughter of Zeus, then a statue is only the child of a sculptor, and so is not a god [Stilpo, by Diog. Laertius] |
| Full Idea: Stilpo asked a man whether Athena is the daughter of Zeus, and when he said yes, said,"But this statue of Athena by Phidias is the child of Phidias, so it is not a god." | |
| From: report of Stilpo (fragments/reports [c.330 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 02.10.5 |