26 ideas
17813 | Löwenheim-Skolem says any theory with a true interpretation has a model in the natural numbers [White,NP] |
Full Idea: The Löwenheim-Skolem theorem tells us that any theory with a true interpretation has a model in the natural numbers. | |
From: Nicholas P. White (What Numbers Are [1974], V) |
17812 | Finite cardinalities don't need numbers as objects; numerical quantifiers will do [White,NP] |
Full Idea: Statements involving finite cardinalities can be made without treating numbers as objects at all, simply by using quantification and identity to define numerically definite quantifiers in the manner of Frege. | |
From: Nicholas P. White (What Numbers Are [1974], IV) | |
A reaction: [He adds Quine 1960:268 as a reference] |
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. |
21110 | An understanding of the most basic physics should explain all of the subject's mysteries [Krauss] |
Full Idea: Once we understood the fundamental laws that govern forces of nature at its smallest scales, all of these current mysteries would be revealed as natural consequences of these laws. | |
From: Lawrence M. Krauss (A Universe from Nothing [2012], 08) | |
A reaction: This expresses the reductionist view within physics itself. Krauss says the discovery that empty space itself contains energy has led to a revision of this view (because that is not part of the forces and particles studied in basic physics). |
21105 | In 1676 it was discovered that water is teeming with life [Krauss] |
Full Idea: Van Leeuwenhoek first stared at a drop of seemingly empty water with a microscope in 1676 and discovered in was teeming with life. | |
From: Lawrence M. Krauss (A Universe from Nothing [2012], 04) | |
A reaction: I am convinced that this had a huge influence on Leibniz's concept of monads. He immediately became convinced that it was some sort of life all the way down. He would be have been disappointed by the subsequent chemical reduction of life. |
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') |
21109 | Space itself can expand (and separate its contents) at faster than light speeds [Krauss] |
Full Idea: Special Relativity says nothing can travel 'through space' faster than the speed of light. But space itself can do whatever the heck it wants, at least in general relativity. And it can carry distant objects apart from one another at superluminal speeds | |
From: Lawrence M. Krauss (A Universe from Nothing [2012], 06) | |
A reaction: Another of my misunderstandings corrected. I assumed that the event horizon (limit of observability) was defined by the stuff retreating at (max) light speed. But beyond that it retreats even faster! What about the photons in space? |
21104 | General Relativity: the density of energy and matter determines curvature and gravity [Krauss] |
Full Idea: The left-hand side of the general relativity equations descrbe the curvature of the universe, and the strength of gravitational forces acting on matter and radiation. The right-hand sides reflect the total density of all kinds of energy and matter. | |
From: Lawrence M. Krauss (A Universe from Nothing [2012], 04) | |
A reaction: I had assumed that the equations just described the geometry. In fact the matter determines the nature of the universe in which it exists. Presumably only things with mass get a vote. |
21107 | Uncertainty says that energy can be very high over very short time periods [Krauss] |
Full Idea: The Heisenberg Uncertainty Principle says that the uncertainty in the measured energy of a system is inversely proportional to the length of time over which you observe it. (This allow near infinite energy over very short times). | |
From: Lawrence M. Krauss (A Universe from Nothing [2012], 04) | |
A reaction: Apparently this brief energy is 'borrowed', and must be quickly repaid. |
21106 | Most of the mass of a proton is the energy in virtual particles (rather than the quarks) [Krauss] |
Full Idea: The quarks provide very little of the total mass of a proton, and the fields created by the virtual particles contribute most of the energy that goes into the proton's rest energy and, hence, its mass. | |
From: Lawrence M. Krauss (A Universe from Nothing [2012], 04) | |
A reaction: He gives an artist's impression of the interior of a proton, which looks like a ship's engine room. |
21112 | Empty space contains a continual flux of brief virtual particles [Krauss] |
Full Idea: Empty space is complicated. It is a boiling brew of virtual particles that pop in and out of existence in a time so short we cannot see them directly. | |
From: Lawrence M. Krauss (A Universe from Nothing [2012], 10) | |
A reaction: Apparently the interior of a proton is also like this. This fact gives a foot in the door for explanations of how the Big Bang got started, from these virtual particles. And yet surely space itself only arrives with the Big Bang? |
21108 | The universe is precisely 13.72 billion years old [Krauss] |
Full Idea: We now know the age of the universe to four significant figures. It is 13.72 billion years old! | |
From: Lawrence M. Krauss (A Universe from Nothing [2012], 05) | |
A reaction: It amazes me how many people, especially in philosophy, would be reluctant to accept that this is a know fact. I'm not accepting its certainty, but an assertion like this from a leading figure is good enough for me, and it should be for you. |
21111 | It seems likely that cosmic inflation is eternal, and this would make a multiverse inevitable [Krauss] |
Full Idea: A multiverse is inevitable if inflation is eternal, and eternal inflation is by far the most likely possibility in most, if not all, inflationary scenarios. | |
From: Lawrence M. Krauss (A Universe from Nothing [2012], 08) |