14 ideas
| 22361 | Contextual values are acceptable in research, but not in its final evaluation [Reichenbach, by Reiss/Sprenger] |
| Full Idea: Reichenbach's claim is interpreted as saying that contextual values, which may have contributed to the discovery of a theory, are irrelevant for justifying the acceptance of a theory, and for assessing how evidence bears on theory. | |
| From: report of Hans Reichenbach (On Probability and Induction [1938], pp.36-7) by Reiss,J/Spreger,J - Scientific Objectivity 3.2 | |
| A reaction: This influential idea is very helpful. It allows Galileo and co to pursus all sorts of highly personal and quirky lines of enquiry, because we only demand full objectivity when it is all over. Very good! |
| 17879 | Axiomatising set theory makes it all relative [Skolem] |
| Full Idea: Axiomatising set theory leads to a relativity of set-theoretic notions, and this relativity is inseparably bound up with every thoroughgoing axiomatisation. | |
| From: Thoralf Skolem (Remarks on axiomatised set theory [1922], p.296) |
| 13536 | Skolem did not believe in the existence of uncountable sets [Skolem] |
| Full Idea: Skolem did not believe in the existence of uncountable sets. | |
| From: Thoralf Skolem (works [1920], 5.3) | |
| A reaction: Kit Fine refers somewhere to 'unrepentent Skolemites' who still hold this view. |
| 17878 | If a 1st-order proposition is satisfied, it is satisfied in a denumerably infinite domain [Skolem] |
| Full Idea: Löwenheim's theorem reads as follows: If a first-order proposition is satisfied in any domain at all, it is already satisfied in a denumerably infinite domain. | |
| From: Thoralf Skolem (Remarks on axiomatised set theory [1922], p.293) |
| 17880 | Integers and induction are clear as foundations, but set-theory axioms certainly aren't [Skolem] |
| Full Idea: The initial foundations should be immediately clear, natural and not open to question. This is satisfied by the notion of integer and by inductive inference, by it is not satisfied by the axioms of Zermelo, or anything else of that kind. | |
| From: Thoralf Skolem (Remarks on axiomatised set theory [1922], p.299) | |
| A reaction: This is a plea (endorsed by Almog) that the integers themselves should be taken as primitive and foundational. I would say that the idea of successor is more primitive than the integers. |
| 17881 | Mathematician want performable operations, not propositions about objects [Skolem] |
| Full Idea: Most mathematicians want mathematics to deal, ultimately, with performable computing operations, and not to consist of formal propositions about objects called this or that. | |
| From: Thoralf Skolem (Remarks on axiomatised set theory [1922], p.300) |
| 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. |
| 18278 | Kant showed that our perceptions are partly constructed from our concepts [Reichenbach] |
| Full Idea: It was Kant's great discovery that the object of knowledge is not simply given but constructed, and that it contains conceptual elements not contained in pure perception. | |
| From: Hans Reichenbach (The Theory of Relativity and A Priori Knowledge [1965], p.49), quoted by J. Alberto Coffa - The Semantic Tradition from Kant to Carnap |
| 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. |
| 8410 | A theory of causal relations yields an asymmetry which defines the direction of time [Reichenbach, by Salmon] |
| Full Idea: Reichenbach wanted to implement a causal theory of time. He did not stipulate that causes are temporally prior to their effects. Instead, he constructs a theory of causal relations to yield a causal asymmetry which is used to define temporal priority. | |
| From: report of Hans Reichenbach (The Direction of Time [1956]) by Wesley Salmon - Probabilistic Causality | |
| A reaction: I find his approach implausible. I suspect strong empiricism is behind it - that he wants to build from observable causes to unobservable time, not vice versa. But normal intuition sees time as one of the bedrocks of reality, making events possible. |
| 14935 | The direction of time is grounded in the direction of causation [Reichenbach, by Ladyman/Ross] |
| Full Idea: Reichenbach argued that temporal asymmetry is grounded in causal asymmetry. | |
| From: report of Hans Reichenbach (The Direction of Time [1956]) by J Ladyman / D Ross - Every Thing Must Go | |
| A reaction: I'm not sure that I can make sense of giving priority either to time or to causation when it comes to this asymmetry. How do you decide which one is boss? |