25 ideas
| 6007 | If you know your father, but don't recognise your father veiled, you know and don't know the same person [Eubulides, by Dancy,R] |
| Full Idea: The 'undetected' or 'veiled' paradox of Eubulides says: if you know your father, and don't know the veiled person before you, but that person is your father, you both know and don't know the same person. | |
| From: report of Eubulides (fragments/reports [c.390 BCE]) by R.M. Dancy - Megarian School | |
| A reaction: Essentially an uninteresting equivocation on two senses of "know", but this paradox comes into its own when we try to give an account of how linguistic reference works. Frege's distinction of sense and reference tried to sort it out (Idea 4976). |
| 6006 | If you say truly that you are lying, you are lying [Eubulides, by Dancy,R] |
| Full Idea: The liar paradox of Eubulides says 'if you state that you are lying, and state the truth, then you are lying'. | |
| From: report of Eubulides (fragments/reports [c.390 BCE]) by R.M. Dancy - Megarian School | |
| A reaction: (also Cic. Acad. 2.95) Don't say it, then. These kind of paradoxes of self-reference eventually lead to Russell's 'barber' paradox and his Theory of Types. |
| 6008 | Removing one grain doesn't destroy a heap, so a heap can't be destroyed [Eubulides, by Dancy,R] |
| Full Idea: The 'sorites' paradox of Eubulides says: if you take one grain of sand from a heap (soros), what is left is still a heap; so no matter how many grains of sand you take one by one, the result is always a heap. | |
| From: report of Eubulides (fragments/reports [c.390 BCE]) by R.M. Dancy - Megarian School | |
| A reaction: (also Cic. Acad. 2.49) This is a very nice paradox, which goes to the heart of our bewilderment when we try to fully understand reality. It homes in on problems of identity, as best exemplified in the Ship of Theseus (Ideas 1212 + 1213). |
| 10496 | Monothetic categories have fixed defining features, and polythetic categories do not [Ellen] |
| Full Idea: Many categories are 'monothetic' (the defining set of features is always unique), and others are 'polythetic' (single features being neither essential to group membership nor sufficient to allocate an item to a group). | |
| From: Roy Ellen (Anthropological Studies of Classification [1996], p.33) | |
| A reaction: This seems a rather important distinction which hasn't made its way into philosophy, where there is a horrible tendency to oversimplify, with the dream of a neat and unified picture. But see Goodman's 'Imperfect Community' problem (Idea 7957). |
| 10497 | In symbolic classification, the categories are linked to rules [Ellen] |
| Full Idea: Symbolic classification occurs when we use some things as a means of saying something about other things. ..They enhance the significance of some categories, so that categories imply rules and rules imply categories. | |
| From: Roy Ellen (Anthropological Studies of Classification [1996], p.35) | |
| A reaction: I'm afraid the anthropologists seem to have more of interest to say about categories than philosophers do. Though maybe we couldn't do anthropology if philosophers had made us more self-conscious about categories. Teamwork! |
| 10494 | Several words may label a category; one word can name several categories; some categories lack words [Ellen] |
| Full Idea: Words are not always a good guide to the existence of categories: there may be several words which label the same categories (synonyms). and the same word can be used for quite different ideas. Some categories may exist without being labelled. | |
| From: Roy Ellen (Categories, Classification, Cogn. Anthropology [2006], I) | |
| A reaction: This is the sort of point which seems obvious to anyone outside philosophy, but which philosophers seem to find difficult to accept. Philosophers should pay much more attention to animals, and to illiterate peoples. Varieties of rice can lack labels. |
| 10495 | Continuous experience sometimes needs imposition of boundaries to create categories [Ellen] |
| Full Idea: Because parts of our experience of the world are complexly continuous, it is occasionally necessary to impose boundaries to produce categories at all. | |
| From: Roy Ellen (Anthropological Studies of Classification [1996], p.33) | |
| A reaction: I like it. Ellen says that people tend to universally cut nature somewhere around the joints, but we can't cope with large things, so the sea tends to be labelled in sections, even though most of the world's seas are continuous. |
| 15127 | A categorical basis could hardly explain a disposition if it had no powers of its own [Hawthorne] |
| Full Idea: The categorical basis would be a poor explanans for the disposition as explanandum, if the categorical basis did not drag any causal powers along with it. | |
| From: John Hawthorne (Causal Structuralism [2001], 2.4) | |
| A reaction: The idea that the world is explained just by some basic stuff having qualities and relations always strikes me as wrong, because the view of nature is too passive. |
| 15123 | Is the causal profile of a property its essence? [Hawthorne] |
| Full Idea: We might say that the causal profile of a property is its essence. | |
| From: John Hawthorne (Causal Structuralism [2001], Intro) | |
| A reaction: I associate this view with Shoemaker, and find it sympathetic. We always want to know more. What gives rise to these causal powers? Where does explanation end? He notes that you might say some of the powers are non-essential. |
| 15122 | Could two different properties have the same causal profile? [Hawthorne] |
| Full Idea: If there is more to the nature of a property than the causal powers that it confers, then two different internal natures of properties might necessitate the same causal profile. | |
| From: John Hawthorne (Causal Structuralism [2001], Intro) | |
| A reaction: If the causal profiles were identical, it is hard to see how we could even propose, let alone test, their intrinsic difference. ...Unless, perhaps, we knew that the properties arose from different substrata. |
| 15124 | If properties are more than their powers, we could have two properties with the same power [Hawthorne] |
| Full Idea: If a property is something over and above its causal profile, we seem to have conceptual space for an electron to have negative charge 1 and negative charge 2, that have exactly the same causal powers. | |
| From: John Hawthorne (Causal Structuralism [2001], 1.3) |
| 14590 | If we accept scattered objects such as archipelagos, why not think of cars that way? [Hawthorne] |
| Full Idea: In being willing to countenance archipelagos, one embraces scattered objects. Why not then embrace the 'archipelago' of my car and the Eiffel Tower? | |
| From: John Hawthorne (Three-Dimensionalism v Four-Dimensionalism [2008], 2.1) | |
| A reaction: This is a beautifully simple and striking point. Language is full of embracing terms like 'the furniture', but that doesn't mean we assume the furniture is unified. The archipelago is less of an 'object' if you live on one of the islands. |
| 15128 | We can treat the structure/form of the world differently from the nodes/matter of the world [Hawthorne] |
| Full Idea: It does not seem altogether arbitrary to treat the structure of the world (the 'form' of the world) in a different way to the nodes in the structure (the 'matter' of the world). | |
| From: John Hawthorne (Causal Structuralism [2001], 2.5) | |
| A reaction: An interesting contemporary spin put on Aristotle's original view. Hawthorne is presenting the Aristotle account as a sort of 'structuralism' about nature. |
| 15121 | An individual essence is a necessary and sufficient profile for a thing [Hawthorne] |
| Full Idea: An individual essence is a profile that is necessary and sufficient for some particular thing. | |
| From: John Hawthorne (Causal Structuralism [2001], Intro) | |
| A reaction: By 'for' he presumably means for the thing to have an existence and a distinct identity. If it retained its identity, but didn't function any more, would that be loss of essence? |
| 14591 | Four-dimensionalists say instantaneous objects are more fundamental than long-lived ones [Hawthorne] |
| Full Idea: Self-proclaimed four-dimensionalists typically adopt a picture that reckons instantaneous objects (and facts about them) to be more fundamental than long-lived ones. | |
| From: John Hawthorne (Three-Dimensionalism v Four-Dimensionalism [2008], 2.2) | |
| A reaction: A nice elucidation. As in Idea 14588, this seems motivated by a desire for some sort of foundationalism or atomism. Why shouldn't a metaphysic treat the middle-sized or temporally extended as foundational, and derive the rest that way? |
| 8970 | Our notion of identical sets involves identical members, which needs absolute identity [Hawthorne] |
| Full Idea: Our conceptual grip on the notion of a set is founded on the axiom of extensionality: a set x is the same as a set y iff x and y have the same members. But this axiom deploys the notion of absolute identity ('same members'). | |
| From: John Hawthorne (Identity [2003], 3.1) | |
| A reaction: Identity seems to be a primitive, useful and crucial concept, so don't ask what it is. I suspect that numbers can't get off the ground without it (especially, in view of the above, if you define numbers in terms of sets). |
| 14589 | A modal can reverse meaning if the context is seen differently, so maybe context is all? [Hawthorne] |
| Full Idea: One person says 'He can't dig a hole; he hasn't got a spade', and another says 'He can dig a hole; just give him a spade', and both uses of the modal 'can' will be true. So some philosophers say that all modal predications are thus context-dependent. | |
| From: John Hawthorne (Three-Dimensionalism v Four-Dimensionalism [2008], 1.2) | |
| A reaction: Quine is the guru for this view of modality. Hawthorne's example seems to me to rely too much on the linguistic feature of contrasting 'can' and 'can't'. The underlying assertion in the propositions says something real about the possibilities. |
| 19553 | Commitment to 'I have a hand' only makes sense in a context where it has been doubted [Hawthorne] |
| Full Idea: If I utter 'I know I have a hand' then I can only be reckoned a cooperative conversant by my interlocutors on the assumption that there was a real question as to whether I have a hand. | |
| From: John Hawthorne (The Case for Closure [2005], 2) | |
| A reaction: This seems to point to the contextualist approach to global scepticism, which concerns whether we are setting the bar high or low for 'knowledge'. |
| 19551 | How can we know the heavyweight implications of normal knowledge? Must we distort 'knowledge'? [Hawthorne] |
| Full Idea: Those who deny skepticism but accept closure will have to explain how we know the various 'heavyweight' skeptical hypotheses to be false. Do we then twist the concept of knowledge to fit the twin desiderata of closue and anti-skepticism? | |
| From: John Hawthorne (The Case for Closure [2005], Intro) | |
| A reaction: [He is giving Dretske's view; Dretske says we do twist knowledge] Thus if I remember yesterday, that has the heavyweight implication that the past is real. Hawthorne nicely summarises why closure produces a philosophical problem. |
| 19552 | We wouldn't know the logical implications of our knowledge if small risks added up to big risks [Hawthorne] |
| Full Idea: Maybe one cannot know the logical consequences of the proposition that one knows, on account of the fact that small risks add up to big risks. | |
| From: John Hawthorne (The Case for Closure [2005], 1) | |
| A reaction: The idea of closure is that the new knowledge has the certainty of logic, and each step is accepted. An array of receding propositions can lose reliability, but that shouldn't apply to logic implications. Assuming monotonic logic, of course. |
| 19554 | Denying closure is denying we know P when we know P and Q, which is absurd in simple cases [Hawthorne] |
| Full Idea: How could we know that P and Q but not be in a position to know that P (as deniers of closure must say)? If my glass is full of wine, we know 'g is full of wine, and not full of non-wine'. How can we deny that we know it is not full of non-wine? | |
| From: John Hawthorne (The Case for Closure [2005], 2) | |
| A reaction: Hawthorne merely raises this doubt. Dretske is concerned with heavyweight implications, but how do you accept lightweight implications like this one, and then suddenly reject them when they become too heavy? [see p.49] |
| 10498 | Classification is no longer held to be rooted in social institutions [Ellen] |
| Full Idea: The view that all classification finds its roots in social institutions is now generally considered untenable. | |
| From: Roy Ellen (Anthropological Studies of Classification [1996], p.36) | |
| A reaction: And about time too. Ellen (an anthropologist) inevitably emphasises the complexity of the situation, but endorses the idea that people everywhere largely cut nature at the joints. |
| 15126 | Maybe scientific causation is just generalisation about the patterns [Hawthorne] |
| Full Idea: Perhaps science doesn't need a robust conception of causation, and can get by with thinking of causal laws in a Humean way, as the simplest generalization over the mosaic. | |
| From: John Hawthorne (Causal Structuralism [2001], 1.5) | |
| A reaction: The Humean view he is referring to is held by David Lewis. That seems a council of defeat. We observe from a distance, but make no attempt to explain. |
| 15125 | We only know the mathematical laws, but not much else [Hawthorne] |
| Full Idea: We know the laws of the physical world, in so far as they are mathematical, pretty well, but we know nothing else about it. | |
| From: John Hawthorne (Causal Structuralism [2001], Ch.25) | |
| A reaction: Lovely remark [spotted by Hawthorne]. This sums up exactly what I take to be the most pressing issue in philosophy of science - that we develop a view of science that has space for the next step in explanation. |
| 14588 | Modern metaphysicians tend to think space-time points are more fundamental than space-time regions [Hawthorne] |
| Full Idea: Nowadays it is common for metaphysicians to hold both that space-time regions are less fundamental than the space-time points that compose them, and that facts about the regions are less fundamental than facts about the points and their arrangements. | |
| From: John Hawthorne (Three-Dimensionalism v Four-Dimensionalism [2008], 1) | |
| A reaction: I'm not quite sure what a physicist would make of this. It seems to be motivated by some a priori preference for atomism, and for system-building from minimal foundations. |