15 ideas
| 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. |
| 22179 | Explanatory facts also predict, and predictive facts also explain [Hempel, by Okasha] |
| Full Idea: Hempel said every scientific explanation is potentially a prediction - it would have predicted the phenomenon in question, had it not already been known. But also the information used to make a prediction is potentially an explanation. | |
| From: report of Carl Hempel (Aspects of Scientific Explanation [1965]) by Samir Okasha - Philosophy of Science: Very Short Intro (2nd ed) 3 | |
| A reaction: Sounds too neatly glib to be quite true. If you explain a single event there is nothing to predict. You might predict accurately from a repetitive pattern, with no understanding at all of the pattern. |
| 21507 | Scientific explanation aims at a unifying account of underlying structures and processes [Hempel] |
| Full Idea: What theoretical scientific explanation aims at is an objective kind of insight that is achieved by a systematic unification, by exhibiting the phenomena as manifestations of common underlying structures and processes that conform to testable principles. | |
| From: Carl Hempel (Philosophy of Natural Science [1967], p.83), quoted by Laurence Bonjour - The Structure of Empirical Knowledge 5.3 | |
| A reaction: This is a pretty good statement of scientific essentialism, and structures and processes are what I take Aristotle to have had in mind when he sought 'what it is to be that thing'. Structures and processes give stability and powers. |
| 6755 | For Hempel, explanations are deductive-nomological or probabilistic-statistical [Hempel, by Bird] |
| Full Idea: Hempel proposes that explanations involve covering laws and antecedent conditions; this view (the 'covering law' view) has two versions, the deductive-nomological model and the probabilistic-statistical model of explanation. | |
| From: report of Carl Hempel (Aspects of Scientific Explanation [1965]) by Alexander Bird - Philosophy of Science Ch.2 | |
| A reaction: The obvious problem with this approach, it seem to me, is that the laws themselves need explanation, and I don't see how a law can be foundational unless there is a divine law-giver. Are the laws arbitrary and axiomatic? |
| 17083 | The covering-law model is for scientific explanation; historical explanation is quite different [Hempel] |
| Full Idea: To put forward the covering-law models of scientific explanation is not to deny that there are other contexts in which we speak of explanation. ….That it does not fit explaining the rules of Hanoverian succession is to miss the intent of our model. | |
| From: Carl Hempel (Aspects of Scientific Explanation [1965], p. 412-3), quoted by David-Hillel Ruben - Explaining Explanation Ch 1 | |
| A reaction: Important to get that clear. It then requires a clear demarcation between science and the rest, and it had better not rule out biology because it is having a love affair with physics. |
| 13052 | Hempel rejects causation as part of explanation [Hempel, by Salmon] |
| Full Idea: Hempel explicitly rejects the idea that causality plays any essential explanatory role. | |
| From: report of Carl Hempel (Aspects of Scientific Explanation [1965], p.352) by Wesley Salmon - Four Decades of Scientific Explanation 1.1 | |
| A reaction: Hempel champions the 'covering-law' model of explanation. It strikes me that Hempel is so utterly wrong about this that his views aren't even a candidate for correctness, but then for a long time his views were orthodoxy. |
| 21650 | No language is semantically referential; it all occurs at the level of thought or utterance [Pietroski, by Hofweber] |
| Full Idea: For Paul Pietroski no expression in natural language is semantically referential. ....Reference to objects occurs not at the level of semantics, but at the level of thought or utterance. | |
| From: report of Paul M. Pietroski (Events and Semantic Architecture [2004]) by Thomas Hofweber - Ontology and the Ambitions of Metaphysics 07.2 | |
| A reaction: Love this. It has always struck me that reference is what speakers do. Try taking any supposedly referential description and sticking 'so-called' in front of it. That seems to leave you with the reference even though you have denied the description. |