22 ideas
| 16541 | All the intrinsic properties of a thing should be deducible from its definition [Spinoza] |
| Full Idea: The definition of a thing should be such that all the properties of that thing, in so far as it is considered by itself, and not in conjunction with other things, can be deduced from it. | |
| From: Baruch de Spinoza (Improvement of Understanding [1675], p.35), quoted by E.J. Lowe - What is the Source of Knowledge of Modal Truths? 6 | |
| A reaction: This is exactly what Locke requires of a real essence (though he is pessimistic about ever achieving it). Spinoza is talking of an Aristotelian real definition, which may be complex, and not a lexicographer's short verbal explication. |
| 15327 | Kripke's semantic theory has actually inspired promising axiomatic theories [Kripke, by Horsten] |
| Full Idea: Kripke has a semantic theory of truth which has inspired promising axiomatic theories of truth. | |
| From: report of Saul A. Kripke (Outline of a Theory of Truth [1975]) by Leon Horsten - The Tarskian Turn 01.2 | |
| A reaction: Feferman produced an axiomatic version of Kripke's semantic theory. |
| 15343 | Kripke offers a semantic theory of truth (involving models) [Kripke, by Horsten] |
| Full Idea: One of the most popular semantic theories of truth is Kripke's theory. It describes a class of models which themselves involve a truth predicate (unlike Tarski's semantic theory). | |
| From: report of Saul A. Kripke (Outline of a Theory of Truth [1975]) by Leon Horsten - The Tarskian Turn 02.3 | |
| A reaction: The modern versions explored by Horsten are syntactic versions of this, derived from Feferman's axiomatisation of the Kripke theory. |
| 14966 | The Tarskian move to a metalanguage may not be essential for truth theories [Kripke, by Gupta] |
| Full Idea: Kripke established that, contrary to the prevalent Tarskian dogma, attributions of truth do not always force a move to a metalanguage. | |
| From: report of Saul A. Kripke (Outline of a Theory of Truth [1975], 5.1) by Anil Gupta - Truth | |
| A reaction: [Gupta also cites Martin and Woodruff 1975] |
| 14967 | Certain three-valued languages can contain their own truth predicates [Kripke, by Gupta] |
| Full Idea: Kripke showed via a fixed-point argument that certain three-valued languages can contain their own truth predicates. | |
| From: report of Saul A. Kripke (Outline of a Theory of Truth [1975]) by Anil Gupta - Truth | |
| A reaction: [Gupta also cites Martin and Woodruff 1975] It is an odd paradox that truth can only be included if one adds a truth-value of 'neither true nor false'. The proposed three-valued system is 'strong Kleene logic'. |
| 16328 | Kripke classified fixed points, and illuminated their use for clarifications [Kripke, by Halbach] |
| Full Idea: Kripke's main contribution was …his classification of the different consistent fixed points and the discussion of their use for discriminating between ungrounded sentences, paradoxical sentences, and so on. | |
| From: report of Saul A. Kripke (Outline of a Theory of Truth [1975]) by Volker Halbach - Axiomatic Theories of Truth 15.1 |
| 17518 | Counting 'coin in this box' may have coin as the unit, with 'in this box' merely as the scope [Ayers] |
| Full Idea: If we count the concept 'coin in this box', we could regard coin as the 'unit', while taking 'in this box' to limit the scope. Counting coins in two boxes would be not a difference in unit (kind of object), but in scope. | |
| From: M.R. Ayers (Individuals without Sortals [1974], 'Counting') | |
| A reaction: This is a very nice alternative to the Fregean view of counting, depending totally on the concept, and rests more on a natural concept of object. I prefer Ayers. Compare 'count coins till I tell you to stop'. |
| 17516 | If counting needs a sortal, what of things which fall under two sortals? [Ayers] |
| Full Idea: If we accepted that counting objects always presupposes some sortal, it is surely clear that the class of objects to be counted could be designated by two sortals rather than one. | |
| From: M.R. Ayers (Individuals without Sortals [1974], 'Realist' vii) | |
| A reaction: His nice example is an object which is both 'a single piece of wool' and a 'sweater', which had better not be counted twice. Wiggins struggles to argue that there is always one 'substance sortal' which predominates. |
| 17520 | Events do not have natural boundaries, and we have to set them [Ayers] |
| Full Idea: In order to know which event has been ostensively identified by a speaker, the auditor must know the limits intended by the speaker. ...Events do not have natural boundaries. | |
| From: M.R. Ayers (Individuals without Sortals [1974], 'Concl') | |
| A reaction: He distinguishes events thus from natural objects, where the world, to a large extent, offers us the boundaries. Nice point. |
| 17519 | To express borderline cases of objects, you need the concept of an 'object' [Ayers] |
| Full Idea: The only explanation of the power to produce borderline examples like 'Is this hazelnut one object or two?' is the possession of the concept of an object. | |
| From: M.R. Ayers (Individuals without Sortals [1974], 'Counting') |
| 17510 | Speakers need the very general category of a thing, if they are to think about it [Ayers] |
| Full Idea: If a speaker indicates something, then in order for others to catch his reference they must know, at some level of generality, what kind of thing is indicated. They must categorise it as event, object, or quality. Thinking about something needs that much. | |
| From: M.R. Ayers (Individuals without Sortals [1974], Intro) | |
| A reaction: Ayers defends the view that such general categories are required, but not the much narrower sortal terms defended by Geach and Wiggins. I'm with Ayers all the way. 'What the hell is that?' |
| 17522 | We use sortals to classify physical objects by the nature and origin of their unity [Ayers] |
| Full Idea: Sortals are the terms by which we intend to classify physical objects according to the nature and origin of their unity. | |
| From: M.R. Ayers (Individuals without Sortals [1974], 'Concl') | |
| A reaction: This is as opposed to using sortals for the initial individuation. I take the perception of the unity to come first, so resemblance must be mentioned, though it can be an underlying (essentialist) resemblance. |
| 17515 | Seeing caterpillar and moth as the same needs continuity, not identity of sortal concepts [Ayers] |
| Full Idea: It is unnecessary to call moths 'caterpillars' or caterpillars 'moths' to see that they can be the same individual. It may be that our sortal concepts reflect our beliefs about continuity, but our beliefs about continuity need not reflect our sortals. | |
| From: M.R. Ayers (Individuals without Sortals [1974], 'Realist' vi) | |
| A reaction: Something that metamorphosed through 15 different stages could hardly required 15 different sortals before we recognised the fact. Ayers is right. |
| 17511 | Recognising continuity is separate from sortals, and must precede their use [Ayers] |
| Full Idea: The recognition of the fact of continuity is logically independent of the possession of sortal concepts, whereas the formation of sortal concepts is at least psychologically dependent upon the recognition of continuity. | |
| From: M.R. Ayers (Individuals without Sortals [1974], Intro) | |
| A reaction: I take this to be entirely correct. I might add that unity must also be recognised. |
| 17517 | Could the same matter have more than one form or principle of unity? [Ayers] |
| Full Idea: The abstract question arises of whether the same matter could be subject to more than one principle of unity simultaneously, or unified by more than one 'form'. | |
| From: M.R. Ayers (Individuals without Sortals [1974], 'Realist' vii) | |
| A reaction: He suggests that the unity of the sweater is destroyed by unravelling, and the unity of the thread by cutting. |
| 17513 | If there are two objects, then 'that marble, man-shaped object' is ambiguous [Ayers] |
| Full Idea: The statue is marble and man-shaped, but so is the piece of marble. So not only are the two objects in the same place, but two marble and man-shaped objects in the same place, so 'that marble, man-shaped object' must be ambiguous or indefinite. | |
| From: M.R. Ayers (Individuals without Sortals [1974], 'Prob') | |
| A reaction: It strikes me as basic that it can't be a piece of marble if you subtract its shape, and it can't be a statue if you subtract its matter. To treat a statue as an object, separately from its matter, is absurd. |
| 17523 | Sortals basically apply to individuals [Ayers] |
| Full Idea: Sortals, in their primitive use, apply to the individual. | |
| From: M.R. Ayers (Individuals without Sortals [1974], 'Concl') | |
| A reaction: If the sortal applies to the individual, any essence must pertain to that individual, and not to the class it has been placed in. |
| 17521 | You can't have the concept of a 'stage' if you lack the concept of an object [Ayers] |
| Full Idea: It would be impossible for anyone to have the concept of a stage who did not already possess the concept of a physical object. | |
| From: M.R. Ayers (Individuals without Sortals [1974], 'Concl') |
| 17514 | Temporal 'parts' cannot be separated or rearranged [Ayers] |
| Full Idea: Temporally extended 'parts' are still mysteriously inseparable and not subject to rearrangement: a thing cannot be cut temporally in half. | |
| From: M.R. Ayers (Individuals without Sortals [1974], 'Prob') | |
| A reaction: A nice warning to anyone accepting a glib analogy between spatial parts and temporal parts. |
| 17509 | Some say a 'covering concept' completes identity; others place the concept in the reference [Ayers] |
| Full Idea: Some hold that the 'covering concept' completes the incomplete concept of identity, determining the kind of sameness involved. Others strongly deny the identity itself is incomplete, and locate the covering concept within the necessary act of reference. | |
| From: M.R. Ayers (Individuals without Sortals [1974], Intro) | |
| A reaction: [a bit compressed; Geach is the first view, and Quine the second; Wiggins is somewhere between the two] |
| 17512 | If diachronic identities need covering concepts, why not synchronic identities too? [Ayers] |
| Full Idea: Why are covering concepts required for diachronic identities, when they must be supposed unnecessary for synchronic identities? | |
| From: M.R. Ayers (Individuals without Sortals [1974], 'Prob') |
| 13073 | To understand the properties we must know the essence, as with a circle [Spinoza] |
| Full Idea: If a circle is defined as a figure in which lines from centre to circumference are equal, such definitions do not explain the essence of a circle, but only a property. The properties of a thing are not understood as long as their essences are not known. | |
| From: Baruch de Spinoza (Improvement of Understanding [1675], §95), quoted by Cover,J/O'Leary-Hawthorne,J - Substance and Individuation in Leibniz 1.2.1 | |
| A reaction: This is the traditional Aristotelian view of essence, and the example of a circle is nice, though I am not sure what the essence of a circle might be. Presumably ALL the properties of a circle must flow from it. |