22 ideas
| 5784 | In its primary and formal sense, 'true' applies to propositions, not beliefs [Russell] |
| Full Idea: We call a belief true when it is belief in a true proposition, ..but it is to propositions that the primary formal meanings of 'truth' and 'falsehood' apply. | |
| From: Bertrand Russell (On Propositions: What they are, and Meaning [1919], §IV) | |
| A reaction: I think this is wrong. A proposition such as 'it is raining' would need a date-and-time stamp to be a candidate for truth, and an indexical statement such as 'I am ill' would need to be asserted by a person. Of course, books can contain unread truths. |
| 5777 | The truth or falsehood of a belief depends upon a fact to which the belief 'refers' [Russell] |
| Full Idea: I take it as evident that the truth or falsehood of a belief depends upon a fact to which the belief 'refers'. | |
| From: Bertrand Russell (On Propositions: What they are, and Meaning [1919], p.285) | |
| A reaction: A nice bold commitment to a controversial idea. The traditional objection is to ask how you are going to formulate the 'facts' except in terms of more beliefs, so you ending up comparing beliefs. Facts are a metaphysical commitment, not an acquaintance. |
| 5783 | Propositions of existence, generalities, disjunctions and hypotheticals make correspondence tricky [Russell] |
| Full Idea: The correspondence of proposition and fact grows increasingly complicated as we pass to more complicated types of propositions: existence-propositions, general propositions, disjunctive and hypothetical propositions, and so on. | |
| From: Bertrand Russell (On Propositions: What they are, and Meaning [1919], §IV) | |
| A reaction: An important point. Truth must not just work for 'it is raining', but also for maths, logic, tautologies, laws etc. This is why so many modern philosophers have retreated to deflationary and minimal accounts of truth, which will cover all cases. |
| 17697 | The existence of an arbitrarily large number refutes the idea that numbers come from experience [Hilbert] |
| Full Idea: The standpoint of pure experience seems to me to be refuted by the objection that the existence, possible or actual, of an arbitrarily large number can never be derived through experience, that is, through experiment. | |
| From: David Hilbert (On the Foundations of Logic and Arithmetic [1904], p.130) | |
| A reaction: Alternatively, empiricism refutes infinite numbers! No modern mathematician will accept that, but you wonder in what sense the proposed entities qualify as 'numbers'. |
| 17698 | Logic already contains some arithmetic, so the two must be developed together [Hilbert] |
| Full Idea: In the traditional exposition of the laws of logic certain fundamental arithmetic notions are already used, for example in the notion of set, and to some extent also of number. Thus we turn in a circle, and a partly simultaneous development is required. | |
| From: David Hilbert (On the Foundations of Logic and Arithmetic [1904], p.131) | |
| A reaction: If the Axiom of Infinity is meant, it may be possible to purge the arithmetic from the logic. Then the challenge to derive arithmetic from it becomes rather tougher. |
| 17486 | Supervenience is simply modally robust property co-variance [Hendry] |
| Full Idea: Supervenience is not an ontological relationship, being just modally robust property co-variance. | |
| From: Robin F. Hendry (Chemistry [2008], 'Ontol') | |
| A reaction: I take supervenience to be nothing more than an interesting phenomenon that requires explanation. I suppose Humean Supervenience is a priori metaphysics, since you could hardly explain it. |
| 5780 | The three questions about belief are its contents, its success, and its character [Russell] |
| Full Idea: There are three issues about belief: 1) the content which is believed, 2) the relation of the content to its 'objective' - the fact which makes it true or false, and 3) the element which is belief, as opposed to consideration or doubt or desire. | |
| From: Bertrand Russell (On Propositions: What they are, and Meaning [1919], §III) | |
| A reaction: The correct answers to the questions (trust me) are that propositions are the contents, the relation aimed at is truth, which is a 'metaphysical ideal' of correspondence to facts, and belief itself is an indefinable feeling. See Hume, Idea 2208. |
| 17481 | Nuclear charge (plus laws) explains electron structure and spectrum, but not vice versa [Hendry] |
| Full Idea: Given relevant laws of nature (quantum mechanics, the exclusion principle) nuclear charge determines and explains electronic structure and spectroscopic behaviour, but not vice versa. | |
| From: Robin F. Hendry (Chemistry [2008], 'Micro') | |
| A reaction: I argue that the first necessary condition for essentialism is a direction of explanation, and here we seem to have one. |
| 5778 | If we object to all data which is 'introspective' we will cease to believe in toothaches [Russell] |
| Full Idea: If privacy is the main objection to introspective data, we shall have to include among such data all sensations; a toothache, for example, is essentially private; a dentist may see the bad condition of your tooth, but does not feel your ache. | |
| From: Bertrand Russell (On Propositions: What they are, and Meaning [1919], §II) | |
| A reaction: Russell was perhaps the first to see why eliminative behaviourism is a non-starter as a theory of mind. Mental states are clearly a cause of behaviour, so they can't be the same thing. We might 'eliminate' mental states by reducing them, though. |
| 5779 | There are distinct sets of psychological and physical causal laws [Russell] |
| Full Idea: There do seem to be psychological and physical causal laws which are distinct from each other. | |
| From: Bertrand Russell (On Propositions: What they are, and Meaning [1919], §II) | |
| A reaction: This sounds like the essence of 'property dualism'. Reductive physicalists (like myself) say there is no distinction. Davidson, usually considered a property dualist, claims there are no psycho-physical laws. Russell notes that reduction may be possible. |
| 5781 | Our important beliefs all, if put into words, take the form of propositions [Russell] |
| Full Idea: The important beliefs, even if they are not the only ones, are those which, if rendered into explicit words, take the form of a proposition. | |
| From: Bertrand Russell (On Propositions: What they are, and Meaning [1919], §III) | |
| A reaction: This assertion is close to the heart of the twentieth century linking of ontology and epistemology to language. It is open to challenges. Why is non-propositional belief unimportant? Do dogs have important beliefs? Can propositions exist non-verbally? |
| 5782 | A proposition expressed in words is a 'word-proposition', and one of images an 'image-proposition' [Russell] |
| Full Idea: I shall distinguish a proposition expressed in words as a 'word-proposition', and one consisting of images as an 'image-proposition'. | |
| From: Bertrand Russell (On Propositions: What they are, and Meaning [1919], §III) | |
| A reaction: This, I think, is good, though it raises the question of what exactly an 'image' is when it is non-visual, as when a dog believes its owner called. This distinction prevents us from regarding all knowledge and ontology as verbal in form. |
| 5776 | A proposition is what we believe when we believe truly or falsely [Russell] |
| Full Idea: A proposition may be defined as: what we believe when we believe truly or falsely. | |
| From: Bertrand Russell (On Propositions: What they are, and Meaning [1919], p.285) | |
| A reaction: If we define belief as 'commitment to truth', Russell's last six words become redundant. "Propositions are the contents of beliefs", it being beliefs which are candidates for truth, not propositions. (Russell agrees, on p.308!) |
| 17478 | Maybe two kinds are the same if there is no change of entropy on isothermal mixing [Hendry] |
| Full Idea: One suggestion is that any two different substance, however alike, exhibit a positive entropy change on mixing. So absence of entropy change on isothermal mixing provides a criterion of sameness of kind. | |
| From: Robin F. Hendry (Chemistry [2008], 'Micro') | |
| A reaction: [He cites Paul Needham 2000] This sounds nice, because at a more amateur level we can say that stuff is the same if mixing two samples of it produces no difference. I call it the Upanishads Test. |
| 17484 | Maybe the nature of water is macroscopic, and not in the microstructure [Hendry] |
| Full Idea: Some deny that that microstructure is what makes it water; substance identity and difference should be determined instead by macroscopic similarities and differences. | |
| From: Robin F. Hendry (Chemistry [2008], 'Micro') | |
| A reaction: Very plausible. Is the essential nature of human beings to be found in the structure of our cells? |
| 17479 | The nature of an element must survive chemical change, so it is the nucleus, not the electrons [Hendry] |
| Full Idea: Whatever earns something membership of the extension of 'krypton' must be a property that can survive chemical change and, therefore, the gain and loss of electrons. Hence what makes it krypton must be a nuclear property. | |
| From: Robin F. Hendry (Chemistry [2008], 'Micro') | |
| A reaction: A very nice illuminating example of essentialism in chemistry. The 'nature' is what survives through change, just like what Aristotle said, innit? |
| 17485 | Maybe water is the smallest part of it that still counts as water (which is H2O molecules) [Hendry] |
| Full Idea: If they do count as water, individual H2O molecules are the smallest items that can qualify as water on their own account. Hydroxyl ions and protons, in contrast, qualify as water only as part of a larger body. | |
| From: Robin F. Hendry (Chemistry [2008], 'Micro') | |
| A reaction: As Aristotle might say, this is the homoeomerous aspect of water. This is Hendry's own proposal, and seems rather good. |
| 17482 | Compounds can differ with the same collection of atoms, so structure matters too [Hendry] |
| Full Idea: The distinctness of the isomers ethanol (CH3CH2OH, boiling at 78.4°) and dimethyl ether (CH3OCH3, boiling at -24.9°) must lie in their different molecular structures. ...But structure has continuously varying quantities, like bond length and angle. | |
| From: Robin F. Hendry (Chemistry [2008], 'Micro') | |
| A reaction: [compressed] This seems to imply that what matters is an idealised abstraction of the structure (i.e. its topology), which is a reason for denying that chemistry is reducible to mere physics. |
| 17483 | Water continuously changes, with new groupings of molecules [Hendry] |
| Full Idea: Macroscopic bodies of water are complex and dynamic congeries of different molecular species, in which there is a constant dissociation of individual molecules, re-association of ions, and formation, growth and disassociation of oligomers. | |
| From: Robin F. Hendry (Chemistry [2008], 'Micro') | |
| A reaction: The point is that these activities are needed to explain the behaviour of water (such as its conductivity). |
| 17476 | Elements survive chemical change, and are tracked to explain direction and properties [Hendry] |
| Full Idea: Elements survive chemical change, and chemical explanations track them from one composite substance to another, thereby explaining both the direction of the chemical change, and the properties of the substances they compose. | |
| From: Robin F. Hendry (Chemistry [2008], Intro) | |
| A reaction: [The 16,000th idea of this database, entered on Guy Fawkes' Day 2013] |
| 17477 | Defining elements by atomic number allowed atoms of an element to have different masses [Hendry] |
| Full Idea: In 1923 elements were defined as populations of atoms with the same nuclear charge (i.e. atomic number), allowing that atoms of the same element may have different masses. | |
| From: Robin F. Hendry (Chemistry [2008], 'Chem') | |
| A reaction: The point is that it allowed isotopes of the same element to come under one heading. This is fine for the heavier elements, but a bit dubious for the very light ones (where an isotope makes a bigger difference). |
| 17480 | Generally it is nuclear charge (not nuclear mass) which determines behaviour [Hendry] |
| Full Idea: In general, nuclear charge is the overwhelming determinant of an element's chemical behaviour, while nuclear mass is a negligible factor. | |
| From: Robin F. Hendry (Chemistry [2008], 'Micro') | |
| A reaction: The exception is the isotopes of very light elements light hydrogen. |