16 ideas
| 3745 | Must sentences make statements to qualify for truth? [O'Connor] |
| Full Idea: Maybe a sentence is not a candidate for truth until it is used to make a statement. | |
| From: D.J. O'Connor (The Correspondence Theory of Truth [1975], Ch.6) |
| 3742 | Beliefs must match facts, but also words must match beliefs [O'Connor] |
| Full Idea: Our beliefs must claim a correspondence with facts, and then the verbal expression of the belief must correspond to the belief itself. | |
| From: D.J. O'Connor (The Correspondence Theory of Truth [1975], Ch.4) |
| 3744 | The semantic theory requires sentences as truth-bearers, not propositions [O'Connor] |
| Full Idea: The Semantic Theory of truth requires that sentences are truth-bearers (rather than statements, or propositions). | |
| From: D.J. O'Connor (The Correspondence Theory of Truth [1975], Ch.6) |
| 3749 | What does 'true in English' mean? [O'Connor] |
| Full Idea: We do not seem to have any use in ordinary discourse for phrases like 'true in English', 'false in German'. | |
| From: D.J. O'Connor (The Correspondence Theory of Truth [1975], II.1) |
| 3746 | Logic seems to work for unasserted sentences [O'Connor] |
| Full Idea: If sentences can have truth-values only when they occur as asserted, it would be impossible to have a truth-functional basis to logic. | |
| From: D.J. O'Connor (The Correspondence Theory of Truth [1975], Ch.6) |
| 13472 | Hilbert aimed to eliminate number from geometry [Hilbert, by Hart,WD] |
| Full Idea: One of Hilbert's aims in 'The Foundations of Geometry' was to eliminate number [as measure of lengths and angles] from geometry. | |
| From: report of David Hilbert (Foundations of Geometry [1899]) by William D. Hart - The Evolution of Logic 2 | |
| A reaction: Presumably this would particularly have to include the elimination of ratios (rather than actual specific lengths). |
| 9546 | Euclid axioms concerns possibilities of construction, but Hilbert's assert the existence of objects [Hilbert, by Chihara] |
| Full Idea: Hilbert's geometrical axioms were existential in character, asserting the existence of certain geometrical objects (points and lines). Euclid's postulates do not assert the existence of anything; they assert the possibility of certain constructions. | |
| From: report of David Hilbert (Foundations of Geometry [1899]) by Charles Chihara - A Structural Account of Mathematics 01.1 | |
| A reaction: Chihara says geometry was originally understood modally, but came to be understood existentially. It seems extraordinary to me that philosophers of mathematics can have become more platonist over the centuries. |
| 18742 | Hilbert's formalisation revealed implicit congruence axioms in Euclid [Hilbert, by Horsten/Pettigrew] |
| Full Idea: In his formal investigation of Euclidean geometry, Hilbert uncovered congruence axioms that implicitly played a role in Euclid's proofs but were not explicitly recognised. | |
| From: report of David Hilbert (Foundations of Geometry [1899]) by Horsten,L/Pettigrew,R - Mathematical Methods in Philosophy 2 | |
| A reaction: The writers are offering this as a good example of the benefits of a precise and formal approach to foundational questions. It's hard to disagree, but dispiriting if you need a PhD in maths before you can start doing philosophy. |
| 18217 | Hilbert's geometry is interesting because it captures Euclid without using real numbers [Hilbert, by Field,H] |
| Full Idea: Hilbert's formulation of the Euclidean theory is of special interest because (besides being rigorously axiomatised) it does not employ the real numbers in the axioms. | |
| From: report of David Hilbert (Foundations of Geometry [1899]) by Hartry Field - Science without Numbers 3 | |
| A reaction: Notice that this job was done by Hilbert, and not by the fictionalist Hartry Field. |
| 3747 | Events are fast changes which are of interest to us [O'Connor] |
| Full Idea: The standard cases of events are physical changes which happen sufficiently fast to be observed as changes, and which are of sufficient interest to us to be noticed or commented on. | |
| From: D.J. O'Connor (The Correspondence Theory of Truth [1975], Ch.7) |
| 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. |
| 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? |
| 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. |
| 3743 | We can't contemplate our beliefs until we have expressed them [O'Connor] |
| Full Idea: It is only when beliefs are given some symbolic expression that they acquire the precision and stability that enables us to entertain them. | |
| From: D.J. O'Connor (The Correspondence Theory of Truth [1975], Ch.5) |
| 3748 | Without language our beliefs are particular and present [O'Connor] |
| Full Idea: Without language we would be restricted to particular beliefs about the here and now. | |
| From: D.J. O'Connor (The Correspondence Theory of Truth [1975], Ch.8) |
| 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. |