37 ideas
| 17325 | Truth-maker theory can't cope with non-causal dependence [Liggins] |
| Full Idea: My charge is that truth-maker theory cannot be integrated into an attractive general account of non-causal dependence. | |
| From: David Liggins (Truth-makers and dependence [2012], 10.6) | |
| A reaction: [You'll have to read Liggins to see why] |
| 17318 | Truthmakers for existence is fine; otherwise maybe restrict it to synthetic truths? [Liggins] |
| Full Idea: Many philosophers agree that true existential propositions have a truth-maker, but some go further, claiming that every true proposition has a truth-maker. More cautious theorists specify a class of truths, such as synthetic propositions. | |
| From: David Liggins (Truth-makers and dependence [2012], 10.1) | |
| A reaction: [compressed; Armstrong is the ambitious one, and Rodriguez-Pereyra proposes the synthetic propositions] Presumably synthetic propositions can make negative assertions, which are problematic for truth-makers. |
| 17610 | The Axiom of Choice paradoxically allows decomposing a sphere into two identical spheres [Maddy] |
| Full Idea: One feature of the Axiom of Choice that troubled many mathematicians was the so-called Banach-Tarski paradox: using the Axiom, a sphere can be decomposed into finitely many parts and those parts reassembled into two spheres the same size as the original. | |
| From: Penelope Maddy (Defending the Axioms [2011], 1.3) | |
| A reaction: (The key is that the parts are non-measurable). To an outsider it is puzzling that the Axiom has been universally accepted, even though it produces such a result. Someone can explain that, I'm sure. |
| 17620 | Critics of if-thenism say that not all starting points, even consistent ones, are worth studying [Maddy] |
| Full Idea: If-thenism denies that mathematics is in the business of discovering truths about abstracta. ...[their opponents] obviously don't regard any starting point, even a consistent one, as equally worthy of investigation. | |
| From: Penelope Maddy (Defending the Axioms [2011], 3.3) | |
| A reaction: I have some sympathy with if-thenism, in that you can obviously study the implications of any 'if' you like, but deep down I agree with the critics. |
| 17605 | Hilbert's geometry and Dedekind's real numbers were role models for axiomatization [Maddy] |
| Full Idea: At the end of the nineteenth century there was a renewed emphasis on rigor, the central tool of which was axiomatization, along the lines of Hilbert's axioms for geometry and Dedekind's axioms for real numbers. | |
| From: Penelope Maddy (Defending the Axioms [2011], 1.3) |
| 17625 | If two mathematical themes coincide, that suggest a single deep truth [Maddy] |
| Full Idea: The fact that two apparently fruitful mathematical themes turn out to coincide makes it all the more likely that they're tracking a genuine strain of mathematical depth. | |
| From: Penelope Maddy (Defending the Axioms [2011], 5.3ii) |
| 17615 | Every infinite set of reals is either countable or of the same size as the full set of reals [Maddy] |
| Full Idea: One form of the Continuum Hypothesis is the claim that every infinite set of reals is either countable or of the same size as the full set of reals. | |
| From: Penelope Maddy (Defending the Axioms [2011], 2.4 n40) |
| 17618 | Set-theory tracks the contours of mathematical depth and fruitfulness [Maddy] |
| Full Idea: Our set-theoretic methods track the underlying contours of mathematical depth. ...What sets are, most fundamentally, is markers for these contours ...they are maximally effective trackers of certain trains of mathematical fruitfulness. | |
| From: Penelope Maddy (Defending the Axioms [2011], 3.4) | |
| A reaction: This seems to make it more like a map of mathematics than the actual essence of mathematics. |
| 17614 | The connection of arithmetic to perception has been idealised away in modern infinitary mathematics [Maddy] |
| Full Idea: Ordinary perceptual cognition is most likely involved in our grasp of elementary arithmetic, but ...this connection to the physical world has long since been idealized away in the infinitary structures of contemporary pure mathematics. | |
| From: Penelope Maddy (Defending the Axioms [2011], 2.3) | |
| A reaction: Despite this, Maddy's quest is for a 'naturalistic' account of mathematics. She ends up defending 'objectivity' (and invoking Tyler Burge), rather than even modest realism. You can't 'idealise away' the counting of objects. I blame Cantor. |
| 17320 | Either p is true or not-p is true, so something is true, so something exists [Liggins] |
| Full Idea: Either p or not-p. If p, then the proposition 'p' is true. If not p, then the proposition 'not p' is true. Either way, something is true. Thus something exists. | |
| From: David Liggins (Truth-makers and dependence [2012], 10.3 n5) | |
| A reaction: Liggins offers this dodgy argument as an objection to conceptual truths having truth-makers. |
| 17326 | The dependence of {Socrates} on Socrates involves a set and a philosopher, not facts [Liggins] |
| Full Idea: The dependence of {Socrates} on Socrates appears to involve a set and a philosopher, neither of which is a fact. | |
| From: David Liggins (Truth-makers and dependence [2012], 10.6) | |
| A reaction: He points out that defenders of facts as the basis of dependence could find a suitable factual paraphrase here. Socrates is just Socrates, but the singleton has to be understood in a particular way to generate the dependence. |
| 17327 | Non-causal dependence is at present only dimly understood [Liggins] |
| Full Idea: Non-causal dependence is at present only dimly understood. | |
| From: David Liggins (Truth-makers and dependence [2012], 10.8) | |
| A reaction: Not very helpful, you may be thinking, but it is always helpful to know where we have got to in the enquiry. |
| 17322 | Necessities supervene on everything, but don't depend on everything [Liggins] |
| Full Idea: Necessities supervene upon everything, but they do not depend on everything. | |
| From: David Liggins (Truth-makers and dependence [2012], 10.4) | |
| A reaction: I'm not sure if merely existing together counts as sufficiently close to be 'supervenience'. If 2+2 necessitates 4, that hardly seems to 'supervene' on the Eiffel Tower. If so, how close must things be to qualify for supervenience? |
| 4938 | Prior to language, concepts are universals created by self-mapping of brain activity [Edelman/Tononi] |
| Full Idea: Before language is present, concepts depend on the brain's ability to construct 'universals' through higher-order mapping of the activity of the brain's own perceptual and motor maps. | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.15) | |
| A reaction: It should be of great interest to philosophers that one can begin to give a neuro-physiological account of universals. A physical system can be ordered as a database, and universals are the higher branches of a tree-structure of information. |
| 4934 | Cultures have a common core of colour naming, based on three axes of colour pairs [Edelman/Tononi] |
| Full Idea: We seem to have a set of colour axes (red-green, blue-yellow, and light-dark). Color naming in different cultures tend to have universal categories based on these axes, with a few derived or composite categories (e.g. orange, purple, pink, brown, grey). | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.13) | |
| A reaction: This confirms my view of all supposed relativism: that there are degrees of cultural and individual relativism possible, but it is daft to think this goes all the way down, as nature has 'joints', and our minds are part of nature. |
| 17324 | 'Because' can signal an inference rather than an explanation [Liggins] |
| Full Idea: 'Because' can signal an inference rather than an explanation. | |
| From: David Liggins (Truth-makers and dependence [2012], 10.5) | |
| A reaction: Aristotle starts from words like 'why?', but it can be a deceptive approach to explanation. |
| 17321 | Value, constitution and realisation are non-causal dependences that explain [Liggins] |
| Full Idea: 'It is wrong because it produces pain for fun', and 'these constitute a table because they are arranged tablewise', and 'tea is poisonous because it contains arsenic' are clearly non-causal uses of 'because', and neither are they conceptual. | |
| From: David Liggins (Truth-makers and dependence [2012], 10.4) | |
| A reaction: The general line seems to be that any form of determination will underwrite an explanation. He talks later of the 'wrongmaker' and 'poisonmaker' relationships to add to the 'truthmaker'. The table example is the 'object-maker' dependence relation. |
| 17323 | If explanations track dependence, then 'determinative' explanations seem to exist [Liggins] |
| Full Idea: If explanation often tracks dependence, then we have a theoretical reason to expect such explanations to exist. Let us call such explanations 'determinative'. | |
| From: David Liggins (Truth-makers and dependence [2012], 10.4) | |
| A reaction: There seems to be an emerging understanding that this 'determination' relation is central to all of explanation - with causal explanations, for example, being a particular instance of it. I like it. These are real, not conventional, explanations. |
| 4924 | A conscious human being rapidly reunifies its mind after any damage to the brain [Edelman/Tononi] |
| Full Idea: It seems that after a massive stroke or surgical resection, a conscious human being is rapidly "resynthesised" or reunified within the limits of a solipsistic universe that, to outside appearances, is warped and restricted. | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch. 3) | |
| A reaction: Note that there are two types of 'unity of mind'. This comment refers to the unity of seeing oneself as a single person, rather than the smooth unbroken quality of conscious experience. I presume that there is no point in a mind without the first unity. |
| 4932 | A conscious state endures for about 100 milliseconds, known as the 'specious present' [Edelman/Tononi] |
| Full Idea: The 'specious present' (William James), a rough estimate of the duration of a single conscious state, is of the order of 100 milliseconds, meaning that conscious states can change very rapidly. | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.12) | |
| A reaction: A vital feature of our subjective experience of time. I wonder what the figure is for a fly? It suggests that conscious experience really is like a movie film, composed of tiny independent 'frames' of very short duration. |
| 4931 | Consciousness is a process (of neural interactions), not a location, thing, property, connectivity, or activity [Edelman/Tononi] |
| Full Idea: Consciousness is neither a thing, nor a simple property. ..The conscious 'dynamic core' of the brain is a process, not a thing or a place, and is defined in terms of neural interactions, not in terms of neural locations, connectivity or activity. | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.12) | |
| A reaction: This must be of great interest to philosophers. Edelman is adamant that it is not any specific neurons. The nice question is: what would it be like to have your brain slowed down? Presumably we would experience steps in the process. Is he a functionalist? |
| 4923 | The three essentials of conscious experience are privateness, unity and informativeness [Edelman/Tononi] |
| Full Idea: The fundamental aspects of conscious experience that are common to all its phenomenological manifestations are: privateness, unity, and informativeness. | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch. 3) | |
| A reaction: Interesting, coming from neuroscientists. The list strikes me as rather passive. It is no use having good radar if you can't make decisions. Privacy and unity are overrated. Who gets 'informed'? Personal identity must be basic. |
| 4941 | Consciousness can create new axioms, but computers can't do that [Edelman/Tononi] |
| Full Idea: Conscious human thought can create new axioms, which a computer cannot do. | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.17) | |
| A reaction: A nice challenge for the artificial intelligence community! I don't understand their confidence in making this assertion. Nothing in Gödel's Theorem seems to prevent the reassignment of axioms, and Quine implies that it is an easy and trivial game. |
| 4930 | Consciousness arises from high speed interactions between clusters of neurons [Edelman/Tononi] |
| Full Idea: Our hypothesis is that the activity of a group of neurons can contribute directly to conscious experience if it is part of a functional cluster, characterized by strong interactions among a set of neuronal groups over a period of hundreds of milliseconds. | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.12) | |
| A reaction: This is their 'dynamic core' hypothesis. It doesn't get at the Hard Questions about consciousness, but this is a Nobel prize winner hot on the trail of the location of the action. It gives support to functionalism, because the neurons vary. |
| 4929 | Dreams and imagery show the brain can generate awareness and meaning without input [Edelman/Tononi] |
| Full Idea: Dreaming and imagery are striking phenomenological demonstrations that the adult brain can spontaneously and intrinsically produce consciousness and meaning without any direct input from the periphery. | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.11) | |
| A reaction: This offers some support for Searle's claim that brain's produce 'intrinsic' (rather than 'derived') intentionality. Of course, one can have a Humean impressions/ideas theory about how the raw material got there. We SEE meaning in our experiences. |
| 4940 | Physicists see information as a measure of order, but for biologists it is symbolic exchange between animals [Edelman/Tononi] |
| Full Idea: Physicists may define information as a measure of order in a far-from-equilibrium state, but it is best seen as a biological concept which emerged in evolution with animals that were capable of mutual symbolic exchange. | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.17) | |
| A reaction: The physicists' definition seems to open the road to the possibility of non-conscious intentionality (Dennett), where the biological view seems to require consciousness of symbolic meanings (Searle). Tree-rings contain potential information? |
| 4935 | The sensation of red is a point in neural space created by dimensions of neuronal activity [Edelman/Tononi] |
| Full Idea: The pure sensation of red is a particular neural state identified by a point within the N-dimensional neural space defined by the integrated activity of all the group of neurons that constitute the dynamic core. | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.13) | |
| A reaction: This hardly answers the Hard Question (why experience it? why that experience?), but it is interesting to see a neuroscientist fishing for an account of qualia. He says three types of neuron firing generate the dimensions of the 'space'. |
| 4936 | The self is founded on bodily awareness centred in the brain stem [Edelman/Tononi] |
| Full Idea: Structures in the brain stem map the state of the body and its relation to the environment, on the basis of signals with proprioceptive, kinesthetic, somatosensory and autonomic components. We may call these the dimensions of the proto-self. | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.13) | |
| A reaction: It seems to me that there is no free will, but moral responsibility depends on the existence of a Self, and philosophers had better fight for it (are you listening, Hume?). Fortunately neuroscientists seem to endorse it fairly unanimously. |
| 4939 | A sense of self begins either internally, or externally through language and society [Edelman/Tononi] |
| Full Idea: Two extreme views on the development of the self are 'internalist' and 'externalist'. The first starts with a baby's subjective experience, and increasing differentiation as self-consciousness develops. The externalist view requires language and society. | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.15) | |
| A reaction: Edelman rightly warns against this simple dichotomy, but if I have to vote, it is for internalism. I take a sense of self as basic to any mind, even a slug's. What is a mind for, if not to look after the creature? Self makes sensation into mind. |
| 4925 | Brains can initiate free actions before the person is aware of their own decision [Edelman/Tononi] |
| Full Idea: Libet concluded that the cerebral initiation of a spontaneous, freely voluntary act can begin unconsciously, that is, before there is any recallable awareness that a decision to act has already been initiated cerebrally. | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch. 6) | |
| A reaction: We should accept this result. 'Free will' was always a bogus metaphysical concept (invented, I think, because God had to be above natural laws). A person is the source of responsibility, and is the controller of the brain, but not entirely conscious. |
| 4933 | Consciousness is a process, not a thing, as it maintains unity as its composition changes [Edelman/Tononi] |
| Full Idea: The conscious 'dynamic core' of the brain can maintain its unity over time even if its composition may be constantly changing, which is the signature of a process as opposed to a thing. | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.12) | |
| A reaction: This is the functionalists' claim that the mind is 'multiply realisable', since different neurons can maintain the same process. 'Process' strikes me as a much better word than 'function'. These theories capture passive mental life better than active. |
| 4928 | Brain complexity balances segregation and integration, like a good team of specialists [Edelman/Tononi] |
| Full Idea: A theoretical analysis of complexity suggests that neuronal complexity strikes an optimum balance between segregation and integration, which fits the view of the brain as a collection of specialists who talk to each other a lot. | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.11) | |
| A reaction: This is a theoretical point, but comes from a leading neuroscientist, and seems to endorse Fodor's modularity proposal. For a philosopher, one of the issues here is how to reconcile the segregation with the Cartesian unity and personal identity of a mind. |
| 4927 | Information-processing views of the brain assume the existence of 'information', and dubious brain codes [Edelman/Tononi] |
| Full Idea: So-called information-processing views of the brain have been criticized because they typically assume the existence in the world of previously defined information, and often assume the existence of precise neural codes for which there is no evidence. | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.11) | |
| A reaction: Fodor is the target here. Searle is keen that 'intrinsic intentionality' is required to see something as 'information'. It is hard to see how anything acquires significance as it flows through a mechanical process. |
| 4922 | Consciousness involves interaction with persons and the world, as well as brain functions [Edelman/Tononi] |
| Full Idea: We emphatically do not identify consciousness in its full range as arising solely in the brain, since we believe that higher brain functions require interactions both with the world and with other persons. | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Pref) | |
| A reaction: Would you gradually lose higher brain functions if you lived entirely alone? Intriguingly, this sounds like a neuroscientist asserting the necessity for broad content in order to understand the brain. |
| 5793 | Concepts and generalisations result from brain 'global mapping' by 'reentry' [Edelman/Tononi, by Searle] |
| Full Idea: When you get maps all over the brain signalling to each other by reentry you have what Edelman calls 'global mapping', and this allows the system not only to have perceptual categories and generalisation, but also to coordinate perception and action. | |
| From: report of G Edelman / G Tononi (Consciousness: matter becomes imagination [2000]) by John Searle - The Mystery of Consciousness Ch.3 | |
| A reaction: This is the nearest we have got to a proper scientific account of thought (as opposed to untested speculation about Turing machines). Something like this account must be right. A concept is a sustained process, not a static item. |
| 4926 | Concepts arise when the brain maps its own activities [Edelman/Tononi] |
| Full Idea: We propose that concepts arise from the mapping by the brain itself of the activity of the brain's own areas and regions. | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch. 9) | |
| A reaction: Yes. One should add that the brain appears to be physically constructed with the logic of a filing system, which would mean that our concepts were labels for files within the system. Nature generates some of the files, and thinking creates the others. |
| 4937 | Systems that generate a sense of value are basic to the primitive brain [Edelman/Tononi] |
| Full Idea: Early and central in the development of the brain are the dimensions provided by value systems indicating salience for the entire organism. | |
| From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.13) | |
| A reaction: This doesn't quite meet Hume's challenge to find values in the whole of nature, but it matches Charles Taylor's claim that for humans values are knowable a priori. Conditional values can be facts of the whole of nature. "If there is life, x has value..". |