13 ideas
11178 | The essence or definition of an essence involves either a class of properties or a class of propositions [Fine,K] |
Full Idea: If each object has a unique essence or definition, this may be identified with either the class of properties that it essentially has, or with the class of propositions that are true in virtue of what it is. | |
From: Kit Fine (Senses of Essence [1995], §8) | |
A reaction: Elsewhere Fine says that it is easier to work with the propositions view, but that the properties (or predicates) view is probably more fundamental. He goes on here to raise the question of whether either view makes the essence unique. |
8758 | We could talk of open sentences, instead of sets [Chihara, by Shapiro] |
Full Idea: Chihara's programme is to replace talk of sets with talk of open sentences. Instead of speaking of the set of all cats, we talk about the open sentence 'x is a cat'. | |
From: report of Charles Chihara (Constructibility and Mathematical Existence [1990]) by Stewart Shapiro - Thinking About Mathematics 9.2 | |
A reaction: As Shapiro points out, this is following up Russell's view that sets should be replaced with talk of properties. Chihara is expressing it more linguistically. I'm in favour of any attempt to get rid of sets. |
11175 | Logical concepts rest on certain inferences, not on facts about implications [Fine,K] |
Full Idea: The nature of the logical concepts is given, not by certain logical truths, but by certain logical inferences. What properly belongs to disjunction is the inference from p to (p or q), rather than the fact that p implies (p or q). | |
From: Kit Fine (Senses of Essence [1995], §3) | |
A reaction: Does this mean that Fine is wickedly starting with the psychology, rather than with the pure truth of the connection? Frege is shuddering. This view seems to imply that the truth table for 'or' is secondary. |
11176 | The property of Property Abstraction says any suitable condition must imply a property [Fine,K] |
Full Idea: According to the principle of Property Abstraction, there is, for any suitable condition, a property that is possessed by an object just in case it conforms to the condition. This is usually taken to be a second-order logical truth. | |
From: Kit Fine (Senses of Essence [1995], §4) | |
A reaction: Fine objects that it is implied that if Socrates is essentially a man, then he essentially has the property of being a man. Like Fine, I think this conclusion is distasteful. A classification is not a property, at least the way most people use 'property'. |
11174 | A logical truth is true in virtue of the nature of the logical concepts [Fine,K] |
Full Idea: One wants to define a logical truth as one that is true in virtue of the nature of the logical concepts. | |
From: Kit Fine (Senses of Essence [1995], §3) | |
A reaction: This is part of Fine's project to give a revised account of essence, which includes the essence of concepts as well as the essence of objects. Everyone should pay close attention to this project. |
10265 | Chihara's system is a variant of type theory, from which he can translate sentences [Chihara, by Shapiro] |
Full Idea: Chihara's system is a version of type theory. Translate thus: replace variables of sets of type n with level n variables over open sentences, replace membership/predication with satisfaction, and high quantifiers with constructability quantifiers. | |
From: report of Charles Chihara (Constructibility and Mathematical Existence [1990]) by Stewart Shapiro - Philosophy of Mathematics 7.4 |
8759 | We can replace type theory with open sentences and a constructibility quantifier [Chihara, by Shapiro] |
Full Idea: Chihara's system is similar to simple type theory; he replaces each type with variables over open sentences, replaces membership (or predication) with satisfaction, and replaces quantifiers over level 1+ variables with constructability quantifiers. | |
From: report of Charles Chihara (Constructibility and Mathematical Existence [1990]) by Stewart Shapiro - Thinking About Mathematics 9.2 | |
A reaction: This is interesting for showing that type theory may not be dead. The revival of supposedly dead theories is the bread-and-butter of modern philosophy. |
10264 | Introduce a constructibility quantifiers (Cx)Φ - 'it is possible to construct an x such that Φ' [Chihara, by Shapiro] |
Full Idea: Chihara has proposal a modal primitive, a 'constructability quantifier'. Syntactically it behaves like an ordinary quantifier: Φ is a formula, and x a variable. Then (Cx)Φ is a formula, read as 'it is possible to construct an x such that Φ'. | |
From: report of Charles Chihara (Constructibility and Mathematical Existence [1990]) by Stewart Shapiro - Philosophy of Mathematics 7.4 | |
A reaction: We only think natural numbers are infinite because we see no barrier to continuing to count, i.e. to construct new numbers. We accept reals when we know how to construct them. Etc. Sounds promising to me (though not to Shapiro). |
11177 | Can the essence of an object circularly involve itself, or involve another object? [Fine,K] |
Full Idea: Can the essence of an object (ineliminably) involve that object itself (perhaps through self-identity, giving a direct circularity), or have an indirect circularity involving two or more objects (such as admiration between Watson and Holmes). | |
From: Kit Fine (Senses of Essence [1995], §7) | |
A reaction: [compressed] This looks like one of the basic questions which any theory of essentialism must address. |
11173 | Being a man is a consequence of his essence, not constitutive of it [Fine,K] |
Full Idea: If we distinguish 'constitutive' from 'consequential' essence, ..then the essence of Socrates will, in part, be constituted by his being a man. But being a man (or a mountain) will merely be consequential upon, and not constitutive of, his essence. | |
From: Kit Fine (Senses of Essence [1995], §3) | |
A reaction: Yes yes yes. I think it is absurd to say that the class to which something belongs is part of its essential nature, given that it presumably can only belong to the class if it already has a certain essential nature. What did Frankenstein construct? |
11179 | If there are alternative definitions, then we have three possibilities for essence [Fine,K] |
Full Idea: If there are alternative definitions for an essence, we must distinguish three notions. There is the essence as the manifold (the combined definitions), or as the range of alternative definitions (with component essences), or there is the common essence. | |
From: Kit Fine (Senses of Essence [1995], §8) | |
A reaction: Fine opts for the third alternative (what the definitions all have in common) as the best account. He says (p.68) 'definitive' properties come from one definition, and 'essential' properties from every possible definition. |
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. |
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. |