21 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. |
17867 | If a concept is not compact, it will not be presentable to finite minds [Almog] |
Full Idea: If the notion of 'logically following' in your language is not compact, it will not be locally presentable to finite minds. | |
From: Joseph Almog (Nature Without Essence [2010], 02) |
17877 | The number series is primitive, not the result of some set theoretic axioms [Almog] |
Full Idea: On Skolem's account, to 'get' the natural numbers - that primal structure - do not 'look for it' as the satisfier of some abstract (set-theoretic) axiomatic essence; start with that primitive structure. | |
From: Joseph Almog (Nature Without Essence [2010], 12) | |
A reaction: [Skolem 1922 and 1923] Almog says the numbers are just 0,1,2,3,4..., and not some underlying axioms. That makes it sound as if they have nothing in common, and that the successor relation is a coincidence. |
20660 | At one level maths and nature are very similar, suggesting some deeper origin [Wolfram] |
Full Idea: At some rather abstract level one can immediately recognise one basic similarity between nature and mathematics ...this suggests that the overall similarity between mathematics and nature must have a deeper origin. | |
From: Stephen Wolfram (A New Kind of Science [2002], p.772), quoted by Peter Watson - Convergence 17 'Philosophy' | |
A reaction: Personally I think mathematics has been derived by abstracting from the patterns in nature, and then further extrapolating from those abstractions. So the puzzle in nature is not the correspondence with mathematics, but the patterns. |
17872 | Definitionalists rely on snapshot-concepts, instead of on the real processes [Almog] |
Full Idea: The definitionalist errs by abstracting away from differences cosmic processes, freezing real, dynamic processes in snapshot-concepts. | |
From: Joseph Almog (Nature Without Essence [2010], 08) | |
A reaction: You could hardly do science at all if you didn't 'abstract away from the differences in cosmic processes'. We can't write about sea-waves, because they all differ slightly? 'Electron' is a snapshot concept. |
17871 | Fregean meanings are analogous to conceptual essence, defining a kind [Almog] |
Full Idea: Ever since Frege, semantic definitionalists have posited a meaning ('sinn') for a name; the meaning/sinn is their semantic analog to the conceptual essence, as ontologically defining of the kind. | |
From: Joseph Almog (Nature Without Essence [2010], 07) |
17866 | Essential definition aims at existence conditions and structural truths [Almog] |
Full Idea: The essentialist encapsulating formula is meant to be existence-exhaustive (an attribute the satisfaction of which is logically necessary and sufficient to be the thing) and truth-exhaustive (promising all the structural truths). | |
From: Joseph Almog (Nature Without Essence [2010], 01) | |
A reaction: [compressed] If he thinks essentialism means that one short phrase can achieve all this, then it is not surprising that Almog renounces his former essentialism in this essay. He may, however, have misunderstood. He should reread Aristotle. |
17868 | Surface accounts aren't exhaustive as they always allow unintended twin cases [Almog] |
Full Idea: A surface-functional characterisation is not exhaustive. It allows unintended twins, alien intruders with different structures - water lookalikes that are not H2O and lookalike infinite structures that are not the natural numbers. | |
From: Joseph Almog (Nature Without Essence [2010], 03) | |
A reaction: He rests this on the claim in mathematical logic that fully expressive systems are always non-categorical (having unintended twins). Set theory is not fully categorical, but Peano Arithmetic is. Almog's main anti-essentialist argument. |
17870 | Alien 'tigers' can't be tigers if they are not related to our tigers [Almog] |
Full Idea: Animals roaming jungles on some planet at the other end of the galaxy with the tiger-look and the tiger genetic make-up but with a disjoint evolutionary history are not the same species as the earthly tigers. | |
From: Joseph Almog (Nature Without Essence [2010], 10) | |
A reaction: I disagree. If two independent cultures build boats, they are both boats. If we manufacture a tiger which can breed with other tigers, we've made a tiger. His 'tigers' would scream for explanation, precisely because they are tigers. If not, no puzzle. |
17869 | Kripke and Putnam offer an intermediary between real and nominal essences [Almog] |
Full Idea: Kripke and Putnam offer us enhanced essences, still formulable in one short sentence and locally graspable. They offer between Locke's mind-boggling definitive real essence and his mind-friendly but not definitive nominal essence. | |
From: Joseph Almog (Nature Without Essence [2010], 04) | |
A reaction: The solution is to add a 'deep structure' which serves both ends. |
17876 | Individual essences are just cobbled together classificatory predicates [Almog] |
Full Idea: The key for the essentialist is classificatory predication. It is only a subsequent extension of this prime idea that leads us to cobble together enough such essential predications to make an individuative essential property. | |
From: Joseph Almog (Nature Without Essence [2010], 11) | |
A reaction: So the essence is just a cross-reference of all the ways we can think of to classify it? I don't think so. Which are the essential classifications? |
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. |
17873 | Water must be related to water, just as tigers must be related to tigers [Almog] |
Full Idea: It is a blindspot to say that to be a tiger one must come from tigers, but to be water one needn't come from water. ...The error lies in not appreciating that to be water one still must come from somewhere in the cosmos, indeed, from hydrogen and oxygen. | |
From: Joseph Almog (Nature Without Essence [2010], 09) | |
A reaction: A unified picture is indeed desirable, but a better solution is to say that the essence of a tiger is in its structure, not in its origins. There are many ways to produce an artefact. There could be many ways to produce a tiger. |
17864 | Defining an essence comes no where near giving a thing's nature [Almog] |
Full Idea: The natures of things are neither exhausted nor even partially given by 'defining essences'. | |
From: Joseph Almog (Nature Without Essence [2010], Intro) | |
A reaction: A better criticism of essentialism. 'Natures' is a much vaguer word than 'essences', however, because the latter refers to what is stable and important, whereas natures could include any aspect. Being ticklish is in my nature, but not in my essence. |
17863 | Essences promise to reveal reality, but actually drive us away from it [Almog] |
Full Idea: The essentialist line (one I trace to Aristotle, Descartes and Kripke) is driving us away from, not closer to, the real nature of things. It promised a sort of Hubble telescope - essences - able to reveal the deep structure of reality. | |
From: Joseph Almog (Nature Without Essence [2010], Intro) | |
A reaction: I suspect this is tilting at a straw man. No one thinks we should hunt for essences instead of doing normal science. 'Essence' just labels what you've got when you succeed. |
20659 | Space and its contents seem to be one stuff - so space is the only existing thing [Wolfram] |
Full Idea: It seems plausible that both space and its contents should somehow be made of the same stuff - so that in a sense space becomes the only thing in the universe. | |
From: Stephen Wolfram (A New Kind of Science [2002], p.474), quoted by Peter Watson - Convergence 17 'Philosophy' | |
A reaction: I presume the concept of a 'field' is what makes this idea possible. |