19 ideas
| 15375 | If terms change their designations in different states, they are functions from states to objects [Fitting] |
| Full Idea: The common feature of every designating term is that designation may change from state to state - thus it can be formalized by a function from states to objects. | |
| From: Melvin Fitting (Intensional Logic [2007], 3) | |
| A reaction: Specifying the objects sounds OK, but specifying states sounds rather tough. |
| 15376 | Intensional logic adds a second type of quantification, over intensional objects, or individual concepts [Fitting] |
| Full Idea: To first order modal logic (with quantification over objects) we can add a second kind of quantification, over intensions. An intensional object, or individual concept, will be modelled by a function from states to objects. | |
| From: Melvin Fitting (Intensional Logic [2007], 3.3) |
| 15378 | Awareness logic adds the restriction of an awareness function to epistemic logic [Fitting] |
| Full Idea: Awareness logic enriched Hintikka's epistemic models with an awareness function, mapping each state to the set of formulas we are aware of at that state. This reflects some bound on the resources we can bring to bear. | |
| From: Melvin Fitting (Intensional Logic [2007], 3.6.1) | |
| A reaction: [He cites Fagin and Halpern 1988 for this] |
| 15379 | Justication logics make explicit the reasons for mathematical truth in proofs [Fitting] |
| Full Idea: In justification logics, the logics of knowledge are extended by making reasons explicit. A logic of proof terms was created, with a semantics. In this, mathematical truths are known for explicit reasons, and these provide a measure of complexity. | |
| From: Melvin Fitting (Intensional Logic [2007], 3.6.1) |
| 11026 | Classical logic is deliberately extensional, in order to model mathematics [Fitting] |
| Full Idea: Mathematics is typically extensional throughout (we write 3+2=2+3 despite the two terms having different meanings). ..Classical first-order logic is extensional by design since it primarily evolved to model the reasoning of mathematics. | |
| From: Melvin Fitting (Intensional Logic [2007], §1) |
| 11028 | λ-abstraction disambiguates the scope of modal operators [Fitting] |
| Full Idea: λ-abstraction can be used to abstract and disambiguate a predicate. De re is [λx◊P(x)](f) - f has the possible-P property - and de dicto is ◊[λxP(x)](f) - possibly f has the P-property. Also applies to □. | |
| From: Melvin Fitting (Intensional Logic [2007], §3.3) | |
| A reaction: Compare the Barcan formula. Originated with Church in the 1930s, and Carnap 1947, but revived by Stalnaker and Thomason 1968. Because it refers to the predicate, it has a role in intensional versions of logic, especially modal logic. |
| 22121 | The concept of being has only one meaning, whether talking of universals or of God [Duns Scotus, by Dumont] |
| Full Idea: Duns Scotus was the first scholastic to hold that the concept of being and other transcendentals were univocal, not only in application to substance and accidents, but even to God and creatures. | |
| From: report of John Duns Scotus (works [1301]) by Stephen D. Dumont - Duns Scotus p.205 | |
| A reaction: So either it exists or it doesn't. No nonsense about 'subsisting'. Russell flirted with subsistence, but Quine agrees with Duns Scotus (and so do I). |
| 22122 | Being (not sensation or God) is the primary object of the intellect [Duns Scotus, by Dumont] |
| Full Idea: Duns Scotus said the primary object of the created intellect was being, rejecting Aquinas's Aristotelian view that it was limited to the quiddity of the sense particular, and Henry of Ghent's Augustinian view that it was God. | |
| From: report of John Duns Scotus (works [1301]) by Stephen D. Dumont - Duns Scotus p.205 | |
| A reaction: I suppose the 'primary object of the intellect' is the rationalist/empiricism disagreement. So (roughly) Aquinas was an empiricist, Duns Scotus was a rationalist, and Augustine was a transcendentalist? Augustine sounds like Spinoza. |
| 22125 | Duns Scotus was a realist about universals [Duns Scotus, by Dumont] |
| Full Idea: Duns Scotus was a realist on the issue of universals and one of the main adversaries of Ockham's programme of nominalism. | |
| From: report of John Duns Scotus (works [1301]) by Stephen D. Dumont - Duns Scotus p.206 | |
| A reaction: The view of Scotus seems to be the minority view. It is hard to find thinkers who really believe that universals have an independent existence. My interest in Duns Scotus waned when I read this. How does he imagine universals? |
| 22127 | Scotus said a substantial principle of individuation [haecceitas] was needed for an essence [Duns Scotus, by Dumont] |
| Full Idea: Rejecting the standard views that essences are individuated by either actual existence, quantity or matter, Scotus said that the principle of individuation is a further substantial difference added to the species - the so-called haecceitas or 'thisness'. | |
| From: report of John Duns Scotus (works [1301]) by Stephen D. Dumont - Duns Scotus p.206 | |
| A reaction: [Scotus seldom referred to 'haecceitas'] I suppose essences have prior existence, but are too generic, so something must fix an essence as pertaining to this particular object. Is the haecceitas part of the essence, or of the particular? |
| 22126 | Avicenna and Duns Scotus say essences have independent and prior existence [Duns Scotus, by Dumont] |
| Full Idea: Duns Scotus endorsed Avicenna's theory of the common nature, according to which the essences have an independence and priority to their existence as either universal in the mind or singular outside it. | |
| From: report of John Duns Scotus (works [1301]) by Stephen D. Dumont - Duns Scotus p.206 | |
| A reaction: I occasionally meet this weird idea in modern discussions of essence (in Lowe?), and now see its origin. It makes little sense without a divine mind to support the independent essences. Scotus had to add a principle of individuation for essences. |
| 15377 | Definite descriptions pick out different objects in different possible worlds [Fitting] |
| Full Idea: Definite descriptions pick out different objects in different possible worlds quite naturally. | |
| From: Melvin Fitting (Intensional Logic [2007], 3.4) | |
| A reaction: A definite description can pick out the same object in another possible world, or a very similar one, or an object which has almost nothing in common with the others. |
| 22129 | Certainty comes from the self-evident, from induction, and from self-awareness [Duns Scotus, by Dumont] |
| Full Idea: Duns Scotus grounded certitude in the knowledge of self-evident propositions, induction, and awareness of our own state. | |
| From: report of John Duns Scotus (works [1301]) by Stephen D. Dumont - Duns Scotus p.206 | |
| A reaction: Induction looks like the weak link here. |
| 22130 | Scotus defended direct 'intuitive cognition', against the abstractive view [Duns Scotus, by Dumont] |
| Full Idea: Scotus allocated to the intellect a direct, existential awareness of the intelligible object, called 'intuitive cognition', in contrast to abstractive knowledge, which seized the object independently of its presence to the intellect in actual existence. | |
| From: report of John Duns Scotus (works [1301]) by Stephen D. Dumont - Duns Scotus p.206 | |
| A reaction: Presumably if you see a thing, shut your eyes and then know it, that is 'abstractive'. Scotus says open your eyes for proper knowledge. |
| 22128 | Augustine's 'illumination' theory of knowledge leads to nothing but scepticism [Duns Scotus, by Dumont] |
| Full Idea: Scotus rejected Henry of Ghent's defence of Augustine's of knowledge by 'illumination', as leading to nothing but scepticism. ...After this, illumination never made a serious recovery. | |
| From: report of John Duns Scotus (works [1301]) by Stephen D. Dumont - Duns Scotus p.206 |
| 3913 | Maybe imagination is the source of a priori justification [Casullo] |
| Full Idea: Some maintain that experiments in imagination are the source of a priori justification. | |
| From: Albert Casullo (A priori/A posteriori [1992], p.1) | |
| A reaction: What else could assessments of possibility and necessity be based on except imagination? |
| 22131 | The will retains its power for opposites, even when it is acting [Duns Scotus, by Dumont] |
| Full Idea: Scotus said the will is a power for opposites, in the sense that even when actually willing one thing, it retains a real, active power to will the opposite. He detaches the idea of freedom from time and variability. | |
| From: report of John Duns Scotus (works [1301]) by Stephen D. Dumont - Duns Scotus p.206 | |
| A reaction: In the sense that we can abandon an action when in the middle of it, this seems to be correct. Not just 'I could have done otherwise', but 'I don't have to be doing this'. This shows that the will has wide power, but not that it is 'free'. |
| 22123 | The concept of God is the unique first efficient cause, final cause, and most eminent being [Duns Scotus, by Dumont] |
| Full Idea: Duns Scotus establishes God as first efficient cause, as ultimate final cause, and as most eminent being - his so-called 'triple primacy' - and says there is a unique nature within these primacies. | |
| From: report of John Duns Scotus (works [1301]) by Stephen D. Dumont - Duns Scotus p.206 | |
| A reaction: This is the first stage of Duns Scotus's unusually complex argument for God's existence. Asserting the actual infinity of this unique being concludes his argument. |
| 22124 | We can't infer the infinity of God from creation ex nihilo [Duns Scotus, by Dumont] |
| Full Idea: Duns Scotus rejected the traditional argument that the infinity of God can be inferred from creation ex nihilo. | |
| From: report of John Duns Scotus (works [1301]) by Stephen D. Dumont - Duns Scotus p.206 | |
| A reaction: He accepted the infinity of God, however, but not for this reason. I don't know why he rejected it. I suppose the rejected claim is that something has to be infinite, and if it isn't the Cosmos then that leaves God? |