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All the ideas for 'Perception', 'fragments/reports' and 'Structures and Structuralism in Phil of Maths'

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71 ideas

2. Reason / A. Nature of Reason / 1. On Reason
Parmenides was much more cautious about accepting ideas than his predecessors [Simplicius on Parmenides]
     Full Idea: Parmenides would not agree with anything unless it seemed necessary, whereas his predecessors used to come up with unsubstantiated assertions.
     From: comment on Parmenides (fragments/reports [c.474 BCE], A28) by Simplicius - On Aristotle's 'Physics' 9.116.2-
     A reaction: from Eudemus
3. Truth / F. Semantic Truth / 2. Semantic Truth
While true-in-a-model seems relative, true-in-all-models seems not to be [Reck/Price]
     Full Idea: While truth can be defined in a relative way, as truth in one particular model, a non-relative notion of truth is implied, as truth in all models.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §4)
     A reaction: [The article is actually discussing arithmetic] This idea strikes me as extremely important. True-in-all-models is usually taken to be tautological, but it does seem to give a more universal notion of truth. See semantic truth, Tarski, Davidson etc etc.
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
ZFC set theory has only 'pure' sets, without 'urelements' [Reck/Price]
     Full Idea: In standard ZFC ('Zermelo-Fraenkel with Choice') set theory we deal merely with pure sets, not with additional urelements.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §2)
     A reaction: The 'urelements' would the actual objects that are members of the sets, be they physical or abstract. This idea is crucial to understanding philosophy of mathematics, and especially logicism. Must the sets exist, just as the urelements do?
5. Theory of Logic / G. Quantification / 5. Second-Order Quantification
Three types of variable in second-order logic, for objects, functions, and predicates/sets [Reck/Price]
     Full Idea: In second-order logic there are three kinds of variables, for objects, for functions, and for predicates or sets.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §5)
     A reaction: It is interesting that a predicate seems to be the same as a set, which begs rather a lot of questions. For those who dislike second-order logic, there seems nothing instrinsically wicked in having variables ranging over innumerable multi-order types.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
'Analysis' is the theory of the real numbers [Reck/Price]
     Full Idea: 'Analysis' is the theory of the real numbers.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §2)
     A reaction: 'Analysis' began with the infinitesimal calculus, which later built on the concept of 'limit'. A continuum of numbers seems to be required to make that work.
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / a. Axioms for numbers
Mereological arithmetic needs infinite objects, and function definitions [Reck/Price]
     Full Idea: The difficulties for a nominalistic mereological approach to arithmetic is that an infinity of physical objects are needed (space-time points? strokes?), and it must define functions, such as 'successor'.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §4)
     A reaction: Many ontologically austere accounts of arithmetic are faced with the problem of infinity. The obvious non-platonist response seems to be a modal or if-then approach. To postulate infinite abstract or physical entities so that we can add 3 and 2 is mad.
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / e. Peano arithmetic 2nd-order
Peano Arithmetic can have three second-order axioms, plus '1' and 'successor' [Reck/Price]
     Full Idea: A common formulation of Peano Arithmetic uses 2nd-order logic, the constant '1', and a one-place function 's' ('successor'). Three axioms then give '1 is not a successor', 'different numbers have different successors', and induction.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §2)
     A reaction: This is 'second-order' Peano Arithmetic, though it is at least as common to formulate in first-order terms (only quantifying over objects, not over properties - as is done here in the induction axiom). I like the use of '1' as basic instead of '0'!
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Set-theory gives a unified and an explicit basis for mathematics [Reck/Price]
     Full Idea: The merits of basing an account of mathematics on set theory are that it allows for a comprehensive unified treatment of many otherwise separate branches of mathematics, and that all assumption, including existence, are explicit in the axioms.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §4)
     A reaction: I am forming the impression that set-theory provides one rather good model (maybe the best available) for mathematics, but that doesn't mean that mathematics is set-theory. The best map of a landscape isn't a landscape.
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / a. Structuralism
Structuralism emerged from abstract algebra, axioms, and set theory and its structures [Reck/Price]
     Full Idea: Structuralism has emerged from the development of abstract algebra (such as group theory), the creation of axiom systems, the introduction of set theory, and Bourbaki's encyclopaedic survey of set theoretic structures.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §2)
     A reaction: In other words, mathematics has gradually risen from one level of abstraction to the next, so that mathematical entities like points and numbers receive less and less attention, with relationships becoming more prominent.
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / b. Varieties of structuralism
Relativist Structuralism just stipulates one successful model as its arithmetic [Reck/Price]
     Full Idea: Relativist Structuralism simply picks one particular model of axiomatised arithmetic (i.e. one particular interpretation that satisfies the axioms), and then stipulates what the elements, functions and quantifiers refer to.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §4)
     A reaction: The point is that a successful model can be offered, and it doesn't matter which one, like having any sort of aeroplane, as long as it flies. I don't find this approach congenial, though having a model is good. What is the essence of flight?
There are 'particular' structures, and 'universal' structures (what the former have in common) [Reck/Price]
     Full Idea: The term 'structure' has two uses in the literature, what can be called 'particular structures' (which are particular relational systems), but also what can be called 'universal structures' - what particular systems share, or what they instantiate.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §6)
     A reaction: This is a very helpful distinction, because it clarifies why (rather to my surprise) some structuralists turn out to be platonists in a new guise. Personal my interest in structuralism has been anti-platonist from the start.
Pattern Structuralism studies what isomorphic arithmetic models have in common [Reck/Price]
     Full Idea: According to 'pattern' structuralism, what we study are not the various particular isomorphic models of arithmetic, but something in addition to them: a corresponding pattern.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §7)
     A reaction: Put like that, we have to feel a temptation to wield Ockham's Razor. It's bad enough trying to give the structure of all the isomorphic models, without seeking an even more abstract account of underlying patterns. But patterns connect to minds..
There are Formalist, Relativist, Universalist and Pattern structuralism [Reck/Price]
     Full Idea: There are four main variants of structuralism in the philosophy of mathematics - formalist structuralism, relativist structuralism, universalist structuralism (with modal variants), and pattern structuralism.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §9)
     A reaction: I'm not sure where Chihara's later book fits into this, though it is at the nominalist end of the spectrum. Shapiro and Resnik do patterns (the latter more loosely); Hellman does modal universalism; Quine does the relativist version. Dedekind?
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / c. Nominalist structuralism
Formalist Structuralism says the ontology is vacuous, or formal, or inference relations [Reck/Price]
     Full Idea: Formalist Structuralism endorses structural methodology in mathematics, but rejects semantic and metaphysical problems as either meaningless, or purely formal, or as inference relations.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §3)
     A reaction: [very compressed] I find the third option fairly congenial, certainly in preference to rather platonist accounts of structuralism. One still needs to distinguish the mathematical from the non-mathematical in the inference relations.
Maybe we should talk of an infinity of 'possible' objects, to avoid arithmetic being vacuous [Reck/Price]
     Full Idea: It is tempting to take a modal turn, and quantify over all possible objects, because if there are only a finite number of actual objects, then there are no models (of the right sort) for Peano Arithmetic, and arithmetic is vacuously true.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §5)
     A reaction: [compressed; Geoffrey Hellman is the chief champion of this view] The article asks whether we are not still left with the puzzle of whether infinitely many objects are possible, instead of existent.
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / d. Platonist structuralism
Universalist Structuralism is based on generalised if-then claims, not one particular model [Reck/Price]
     Full Idea: Universalist Structuralism is a semantic thesis, that an arithmetical statement asserts a universal if-then statement. We build an if-then statement (using quantifiers) into the structure, and we generalise away from any one particular model.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §5)
     A reaction: There remains the question of what is distinctively mathematical about the highly generalised network of inferences that is being described. Presumable the axioms capture that, but why those particular axioms? Russell is cited as an originator.
Universalist Structuralism eliminates the base element, as a variable, which is then quantified out [Reck/Price]
     Full Idea: Universalist Structuralism is eliminativist about abstract objects, in a distinctive form. Instead of treating the base element (say '1') as an ambiguous referring expression (the Relativist approach), it is a variable which is quantified out.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §5)
     A reaction: I am a temperamental eliminativist on this front (and most others) so this is tempting. I am also in love with the concept of a 'variable', which I take to be utterly fundamental to all conceptual thought, even in animals, and not just a trick of algebra.
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / e. Structuralism critique
The existence of an infinite set is assumed by Relativist Structuralism [Reck/Price]
     Full Idea: Relativist Structuralism must first assume the existence of an infinite set, otherwise there would be no model to pick, and arithmetical terms would have no reference.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §4)
     A reaction: See Idea 10169 for Relativist Structuralism. They point out that ZFC has an Axiom of Infinity.
7. Existence / A. Nature of Existence / 3. Being / a. Nature of Being
No necessity could produce Being either later or earlier, so it must exist absolutely or not at all [Parmenides]
     Full Idea: What necessity impelled Being, if it did spring from nothing, to be produced later or earlier? Thus it must be absolutely, or not at all.
     From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1-
     A reaction: If there is a moment when Being is created, it is reasonable to ask why then, and not some other time? Obviously a conscious God can fill that gap,but that only defers the problem.
Being is not divisible, since it is all alike [Parmenides]
     Full Idea: Being is not divisible, since it is all alike.
     From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1-
     A reaction: A baffling proposal when it appears to be extremely diverse. A microscope would have forced him to rethink somewhat.
Being must be eternal and uncreated, and hence it is timeless [Parmenides]
     Full Idea: Being has no coming-to-be and no destruction, for it is whole of limb, without motion, and without end. And it never was, nor will be, because it is now, a whole all together, one, continuous; for what creation of it will you look for?
     From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1-
     A reaction: That being is eternal is a reasonable speculation, since its creation seems inconceivable. But why think it is without motion, when we see motion everywhere? That was Aristotle's reaction, too.
7. Existence / A. Nature of Existence / 3. Being / d. Non-being
The realm of necessary non-existence cannot be explored, because it is unknowable [Parmenides]
     Full Idea: The other way of enquiry, that IT IS NOT, and IT is bound NOT TO BE, cannot be explored, for you could neither recognise nor express that which IS NOT.
     From: Parmenides (fragments/reports [c.474 BCE], B02), quoted by Simplicius - On Aristotle's 'Physics' 9.116.28-
     A reaction: There is not much to say about that which is not, but quite a lot, I would have thought, about what is 'bound not to be'. What prevents it from being?
There is no such thing as nothing [Parmenides]
     Full Idea: There is no such thing as nothing.
     From: Parmenides (fragments/reports [c.474 BCE], B06), quoted by Simplicius - On Aristotle's 'Physics' 9.86.27-
     A reaction: See Meinong on this. It is not an empty concept, because things can be predicated of nothing, such as weighing less than an apple. CF. the role of zero in arithmetic.
7. Existence / A. Nature of Existence / 3. Being / f. Primary being
Parmenides at least saw Being as the same as Nous, and separate from the sensed realm [Parmenides, by Plotinus]
     Full Idea: Parmenides made some approach to the doctrine of Plato in identifying Being with Intellectual-Principle [Nous] while separating Real Being from the realm of sense.
     From: report of Parmenides (fragments/reports [c.474 BCE]) by Plotinus - The Enneads 5.1.08
     A reaction: The point is that for Parmenides the One is the essence of Being, but for platonists there is something prior to and higher than Being. For Plato it is the Good; for Plotinus it is a revised (non-Being) concept of the One.
7. Existence / B. Change in Existence / 1. Nature of Change
All our concepts of change and permanence are just names, not the truth [Parmenides]
     Full Idea: All things that mortals have established, believing in their truth, are just a name: Becoming and Perishing, Being and Not-Being, and change of position, and alteration of bright colour.
     From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1-
     A reaction: He has to say this, once he has decided that Being is homogeneous eternal unity, but if normal human beliefs are just names, presumably that applies to his views too. Is 'Being' just a name?
7. Existence / D. Theories of Reality / 6. Physicalism
For physicalists, the only relations are spatial, temporal and causal [Robinson,H]
     Full Idea: Spatial, temporal and causal relations are the only respectable candidates for relations for a physicalist.
     From: Howard Robinson (Perception [1994], V.4)
     A reaction: This seems to be true, and is an absolutely crucial principle upon which any respectable physicalist account of the world must be built. It means that physicalists must attempt to explain all mental events in causal terms.
8. Modes of Existence / B. Properties / 6. Categorical Properties
If reality just has relational properties, what are its substantial ontological features? [Robinson,H]
     Full Idea: Some thinkers claim the physical world consists just of relational properties - generally of active powers or fields; ..but an ontology of mutual influences is not an ontology at all unless the possessors of the influence have more substantial features.
     From: Howard Robinson (Perception [1994], IX.3)
     A reaction: I think this idea is one of the keys to wisdom. It is the same problem with functional explanations - you are left asking WHY this thing can have this particular function. Without the buck stopping at essences you are chasing your explanatory tail.
8. Modes of Existence / E. Nominalism / 6. Mereological Nominalism
A nominalist might avoid abstract objects by just appealing to mereological sums [Reck/Price]
     Full Idea: One way for a nominalist to reject appeal to all abstract objects, including sets, is to only appeal to nominalistically acceptable objects, including mereological sums.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §4)
     A reaction: I'm suddenly thinking that this looks very interesting and might be the way to go. The issue seems to be whether mereological sums should be seen as constrained by nature, or whether they are unrestricted. See Mereology in Ontology...|Intrinsic Identity.
9. Objects / E. Objects over Time / 1. Objects over Time
Something must be unchanging to make recognition and knowledge possible [Aristotle on Parmenides]
     Full Idea: Parmenides and Melissus were the first to appreciate that there must be unchanging entities, if recognition and knowledge are to exist.
     From: comment on Parmenides (fragments/reports [c.474 BCE], A25) by Aristotle - On the Heavens 298b14
10. Modality / A. Necessity / 5. Metaphysical Necessity
The first way of enquiry involves necessary existence [Parmenides]
     Full Idea: The first way of enquiry is the one that IT IS, and it is not possible for IT NOT TO BE, which is the way of credibility, for it follows truth.
     From: Parmenides (fragments/reports [c.474 BCE], B02), quoted by Simplicius - On Aristotle's 'Physics' 9.116.28-
     A reaction: also Proclus 'Timeus'
10. Modality / A. Necessity / 8. Transcendental Necessity
Necessity sets limits on being, in order to give it identity [Parmenides]
     Full Idea: Powerful necessity holds Being in the bonds of a limit, which constrains it round about, because divine law decrees that Being shall not be without boundary. For it is not lacking, but if it were spatially infinite, it would lack everything.
     From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1-
11. Knowledge Aims / B. Certain Knowledge / 4. The Cogito
Thinking implies existence, because thinking depends on it [Parmenides]
     Full Idea: To think is the same as the thought that IT IS, for you will not find thinking without Being, on which it depends for its expression.
     From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1-
11. Knowledge Aims / C. Knowing Reality / 1. Perceptual Realism / a. Naïve realism
When a red object is viewed, the air in between does not become red [Robinson,H]
     Full Idea: When the form of red passes from an object to the eye, the air in between does not become red.
     From: Howard Robinson (Perception [1994], 1.2)
     A reaction: This strikes me as a crucial and basic fact which must be faced by any philosopher offering a theory of perception. I would have thought it instantly eliminated any sort of direct or naïve realism. The quale of red is created by my brain.
11. Knowledge Aims / C. Knowing Reality / 1. Perceptual Realism / c. Representative realism
Representative realists believe that laws of phenomena will apply to the physical world [Robinson,H]
     Full Idea: One thing which is meant by saying that the phenomenal world represents or resembles the transcendental physical world is that the scientific laws devised to apply to the former, if correct, also apply (at least approximately) to the latter.
     From: Howard Robinson (Perception [1994], IX.3)
     A reaction: This is not, of course, an argument, or a claim which can be easily substantiated, but it does seem to be a nice statement of a central article of faith for representative realists. The laws of the phenomenal world are the only ones we are going to get.
Representative realists believe some properties of sense-data are shared by the objects themselves [Robinson,H]
     Full Idea: A representative realist believes that at least some of the properties that are ostensively demonstrable in virtue of being exemplified in sense-data are of the same kind as some of those exemplified in physical objects.
     From: Howard Robinson (Perception [1994], VII.5)
     A reaction: It is hard to pin down exactly what is being claimed here. Locke's primary qualities will obviously qualify, but could properties be 'exemplified' in sense-data without them actually being the same as those of the objects?
11. Knowledge Aims / C. Knowing Reality / 2. Phenomenalism
Phenomenalism can be theistic (Berkeley), or sceptical (Hume), or analytic (20th century) [Robinson,H]
     Full Idea: It is useful to identify three kinds of phenomenalism: theistic, sceptical and analytic; the first is represented by Berkeley, the second by Hume, and the third by most twentieth-century phenomenalists.
     From: Howard Robinson (Perception [1994], IX.4)
     A reaction: In Britain the third group is usually represented by A.J.Ayer. My simple objection to all phenomenalists is that they are intellectual cowards because they won't venture to give an explanation of the phenomena which confront them.
12. Knowledge Sources / B. Perception / 1. Perception
Parmenides treats perception and intellectual activity as the same [Theophrastus on Parmenides]
     Full Idea: Parmenides treats perception and intellectual activity as the same.
     From: comment on Parmenides (fragments/reports [c.474 BCE], A46) by Theophrastus - On the Senses 3.1
     A reaction: cf Theaetetus pt 1
Can we reduce perception to acquisition of information, which is reduced to causation or disposition? [Robinson,H]
     Full Idea: Many modern physicalists first analyse perception as no more than the acquisition of beliefs or information through the senses, and then analyse belief and the possession of information in causal or dispositional terms.
     From: Howard Robinson (Perception [1994], V.1)
     A reaction: (He mentions Armstrong, Dretske and Pitcher). A reduction to dispositions implies behaviourism. This all sounds more like an eliminativist strategy than a reductive one. I would start by saying that perception is only information after interpretation.
Would someone who recovered their sight recognise felt shapes just by looking? [Robinson,H]
     Full Idea: Molyneux's Problem is whether someone who was born blind and acquired sight would be able to recognise, on sight, which shapes were which; that is, would they see which shape was the one that felt so-and-so?
     From: Howard Robinson (Perception [1994], VIII.7)
     A reaction: (Molyneux wrote a letter to John Locke about this). It is a good question, and much discussed in modern times. My estimation is that the person would recognise the shapes. We are partly synaesthetic, and see sharpness as well as feeling it.
12. Knowledge Sources / B. Perception / 2. Qualities in Perception / b. Primary/secondary
Secondary qualities have one sensory mode, but primary qualities can have more [Robinson,H]
     Full Idea: Primary qualities and secondary qualities are often distinguished on the grounds that secondaries are restricted to one sensory modality, but primaries can appear in more.
     From: Howard Robinson (Perception [1994], VIII.7)
     A reaction: This distinction seems to me to be accurate and important. It is not just that the two types are phenomenally different - it is that the best explanation is that the secondaries depend on their one sense, but the primaries are independent.
12. Knowledge Sources / B. Perception / 2. Qualities in Perception / c. Primary qualities
We say objects possess no intrinsic secondary qualities because physicists don't need them [Robinson,H]
     Full Idea: The idea that objects do not possess secondary qualities intrinsically rests on the thought that they do not figure in the physicist's account of the world; ..as they are causally idle, no purpose is served by attributing them to objects.
     From: Howard Robinson (Perception [1994], III.1)
     A reaction: On the whole I agree with this, but colours (for example) are not causally idle, as they seem to affect the behaviour of insects. They are properties which can only have a causal effect if there is a brain in their vicinity. Physicists ignore brains.
12. Knowledge Sources / B. Perception / 2. Qualities in Perception / d. Secondary qualities
If objects are not coloured, and neither are sense-contents, we are left saying that nothing is coloured [Robinson,H]
     Full Idea: If there are good reasons for thinking that physical objects are not literally coloured, and one also refuses to attribute them to sense-contents, then one will have the bizarre theory (which has been recently adopted) that nothing is actually coloured.
     From: Howard Robinson (Perception [1994], 1.7)
     A reaction: It seems to me that objects are not literally coloured, that the air in between does not become coloured, and that my brain doesn't turn a funny colour, so that only leaves colour as an 'interior' feature of certain brain states. That's how it is.
Shape can be experienced in different ways, but colour and sound only one way [Robinson,H]
     Full Idea: Shape can be directly experienced by either touch or sight, which are subjectively different; but colour and sound can be directly experienced only through experiences which are subjectively like sight and hearing.
     From: Howard Robinson (Perception [1994], III.1)
     A reaction: This seems to be a key argument in support of the distinction between primary and secondary qualities. It seems to me that the distinction may be challenged and questioned, but to deny it completely (as Berkeley and Hume do) is absurd.
If secondary qualities match senses, would new senses create new qualities? [Robinson,H]
     Full Idea: As secondary qualities are tailored to match senses, a proliferation of senses would lead to a proliferation of secondary qualities.
     From: Howard Robinson (Perception [1994], III.1)
     A reaction: One might reply that if we experienced, say, magnetism, we would just be discerning a new fine grained primary quality, not adding something new to the ontological stock of properties in the world. It is a matter of HOW we experience the magnetism.
12. Knowledge Sources / B. Perception / 3. Representation
Most moderate empiricists adopt Locke's representative theory of perception [Robinson,H]
     Full Idea: The representative theory of perception is found in Locke, and is adopted by most moderate empiricists.
     From: Howard Robinson (Perception [1994], 1.2)
     A reaction: This is, I think, my own position. Anything less than fairly robust realism strikes me as being a bit mad (despite Berkeley's endless assertions that he is preaching common sense), and direct realism seems obviously false.
12. Knowledge Sources / B. Perception / 4. Sense Data / a. Sense-data theory
Sense-data leads to either representative realism or phenomenalism or idealism [Robinson,H]
     Full Idea: The sense-datum theorist is either a representative realist or a phenomenalist (with which we can classify idealism for present purposes).
     From: Howard Robinson (Perception [1994], VII.5)
     A reaction: The only alternative to these two positions seems to be some sort of direct realism. I class myself as a representative realist, as this just seems (after a very little thought about colour blindness) to be common sense. I'm open to persuasion.
12. Knowledge Sources / B. Perception / 4. Sense Data / b. Nature of sense-data
Sense-data do not have any intrinsic intentionality [Robinson,H]
     Full Idea: I understand sense-data as having no intrinsic intentionality; that is, though it may suggest, by habit, things beyond it, in itself it possesses only sensible qualities which do not refer beyond themselves.
     From: Howard Robinson (Perception [1994], 1.1)
     A reaction: This seems right, as the whole point of proposing sense-data was as something neutral between realism and anti-realism
For idealists and phenomenalists sense-data are in objects; representative realists say they resemble objects [Robinson,H]
     Full Idea: For idealists and phenomenalists sense-data are part of physical objects, for objects consist only of actual or actual and possible sense-data; representative realists say they just have an abstract and structural resemblance to objects.
     From: Howard Robinson (Perception [1994], 1.1)
     A reaction: He puts Berkeley, Hume and Mill in the first group, and Locke in the second. Russell belongs in the second. The very fact that there can be two such different theories about the location of sense-data rather discredits the whole idea.
12. Knowledge Sources / B. Perception / 4. Sense Data / d. Sense-data problems
Sense-data are rejected because they are a veil between us and reality, leading to scepticism [Robinson,H]
     Full Idea: Resistance to the sense-datum theory is inspired mainly by the fear that such data constitute a veil of perception which stands between the observer and the external world, threatening scepticism, or even solipsism.
     From: Howard Robinson (Perception [1994], VII.1)
     A reaction: It is very intellectually dishonest to reject any theory because it leads to scepticism or relativism. This is a common failing among quite good professional philosophers. See Idea 241.
12. Knowledge Sources / B. Perception / 8. Adverbial Theory
'Sense redly' sounds peculiar, but 'senses redly-squarely tablely' sounds far worse [Robinson,H]
     Full Idea: 'Sense redly' sounds peculiar, but 'senses redly-squarely' or 'red-squarely' or 'senses redly-squarely-tablely' and other variants sound far worse.
     From: Howard Robinson (Perception [1994], VII.5)
     A reaction: This is a comment on the adverbial theory, which is meant to replace representative theories based on sense-data. The problem is not that it sounds weird; it is that while plain red can be a mode of perception, being a table obviously can't.
Adverbialism sees the contents of sense-experience as modes, not objects [Robinson,H]
     Full Idea: The defining claim of adverbialism is that the contents of sense-experience are modes, not objects, of sensory activity.
     From: Howard Robinson (Perception [1994], VII.5)
     A reaction: This seems quite a good account of simple 'modes' like colour, but not so good when you instantly perceive a house. It never seems wholly satisfactory to sidestep the question of 'what are you perceiving when you perceive red or square?'
If there are only 'modes' of sensing, then an object can no more be red or square than it can be proud or lazy. [Robinson,H]
     Full Idea: If only modes of sensing are ostensively available, ..then it is a category mistake to see any resemblance between what is available and properties of bodies; one could as sensibly say that a physical body is proud or lazy as that it is red or square.
     From: Howard Robinson (Perception [1994], VII.5)
     A reaction: This is an objection to the 'adverbial' theory of perception. It looks to me like a devastating objection, if the theory is meant to cover primary qualities as well as secondary. Red could be a mode of perception, but not square, surely?
12. Knowledge Sources / C. Rationalism / 1. Rationalism
Only reason can prove the truth of facts [Parmenides]
     Full Idea: Reason alone will prove the truth of facts.
     From: Parmenides (fragments/reports [c.474 BCE]), quoted by Diogenes Laertius - Lives of Eminent Philosophers 09.3.3
14. Science / D. Explanation / 1. Explanation / b. Aims of explanation
An explanation presupposes something that is improbable unless it is explained [Robinson,H]
     Full Idea: Any search for an explanation presupposes that there is something in need of an explanation - that is, something which is improbable unless explained.
     From: Howard Robinson (Perception [1994], IX.3)
     A reaction: Elementary enough, but it underlines the human perspective of all explanations. I may need an explanation of baseball, where you don't.
If all possibilities are equal, order seems (a priori) to need an explanation - or does it? [Robinson,H]
     Full Idea: The fact that order requires an explanation seems to be an a priori principle; ..we assume all possibilities are equally likely, and so no striking regularities should emerge; the sceptic replies that a highly ordered sequence is as likely as any other.
     From: Howard Robinson (Perception [1994], IX.3)
     A reaction: An independent notion of 'order' is required. If I write down '14356', and then throw 1 4 3 5 6 on a die, the match is the order; instrinsically 14356 is nothing special. If you threw the die a million times, a run of six sixes seems quite likely.
15. Nature of Minds / B. Features of Minds / 4. Intentionality / a. Nature of intentionality
If intentional states are intrinsically about other things, what are their own properties? [Robinson,H]
     Full Idea: Intentional states are mysterious things; if they are intrinsically about other things, what properties, if any, do they possess intrinsically?
     From: Howard Robinson (Perception [1994], 1.1)
     A reaction: A very nice question, which I suspect to be right at the heart of the tendency towards externalist accounts of the mind. Since you can only talk about the contents of the thoughts, you can't put forward a decent internalist account of what is going on.
17. Mind and Body / E. Mind as Physical / 1. Physical Mind
Physicalism cannot allow internal intentional objects, as brain states can't be 'about' anything [Robinson,H]
     Full Idea: It is generally conceded by reductive physicalists that a state of the brain cannot be intrinsically about anything, for intentionality is not an intrinsic property of anything, so there can be no internal objects for a physicalist.
     From: Howard Robinson (Perception [1994], V.4)
     A reaction: Perhaps it is best to say that 'aboutness' is not a property of physics. We may say that a brain state 'represents' something, because the something caused the brain state, but representations have to be recognised
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / e. The One
The one is without any kind of motion [Parmenides]
     Full Idea: The one is without any kind of motion.
     From: Parmenides (fragments/reports [c.474 BCE]), quoted by Plato - Parmenides 139a
There could be movement within one thing, as there is within water [Aristotle on Parmenides]
     Full Idea: Why does it follow from there being only one thing that it is unmoving, since, for example, water moves internally while remaining one?
     From: comment on Parmenides (fragments/reports [c.474 BCE]) by Aristotle - Physics 186a16
     A reaction: One suspects that Parmenides wasn't used to critical questions like this, and would have sharpened up his theory if it had been subjected to criticism. How big was the One? Maybe Aristotle is the real father of philosophy.
The one can't be divisible, because if it was it could be infinitely divided down to nothing [Parmenides, by Simplicius]
     Full Idea: Since the one is everywhere alike, then if it is divisible, it will be equally divisible everywhere….so let it be divided everywhere. It is obvious that nothing will remain and the whole will vanish, and so (if it is compound) it is composed of nothing.
     From: report of Parmenides (fragments/reports [c.474 BCE]) by Simplicius - On Aristotle's 'Physics' 9.139.5-
     A reaction: he is quoting Porphyry
Defenders of the One say motion needs the void - but that is not part of Being [Parmenides, by Aristotle]
     Full Idea: Defenders of the One say that there could not be motion without a void, and that void is what does not exist, and that nothing that is not belongs to being.
     From: report of Parmenides (fragments/reports [c.474 BCE]) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 325a26
     A reaction: This is why motion is an illusion, a view also supported by the paradoxes of Zeno of Elea. Aristotle goes on to give Democritus's response to this idea. Parmenides was contemplating 'void', before Democritus got to it.
Reason sees reality as one, the senses see it as many [Aristotle on Parmenides]
     Full Idea: Since he is forced to be guided by appearances, he assumes that the one exists from the viewpoint of reason, but that a plurality exists from the viewpoint of the sense, and so he posits two principles and causes - hot and cold.
     From: comment on Parmenides (fragments/reports [c.474 BCE], A24) by Aristotle - Metaphysics 986b27-
     A reaction: A profound thought. Empiricists emphasies experience, and end up with fragmented reality. Reason explains experience, and in the process sees the world as unities (like objects), though a single unity is going too far.
Reality is symmetrical and balanced, like a sphere, with no reason to be greater one way rather than another [Parmenides]
     Full Idea: Since there is a spatial limit, it is complete on every side, like the mass of a well-rounded sphere, equally balanced from its centre in every direction; for it is not bound to be at all either greater or less in this direction or that.
     From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1-
People who say that the cosmos is one forget that they must explain movement [Aristotle on Parmenides]
     Full Idea: Those who assert that the universe is one and a single nature, when they try to give the causes of generation and destruction, miss out the cause of movement.
     From: comment on Parmenides (fragments/reports [c.474 BCE]) by Aristotle - Metaphysics 988b
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / f. Ancient elements
He taught that there are two elements, fire the maker, and earth the matter [Parmenides, by Diog. Laertius]
     Full Idea: He taught that there were two elements, fire and earth; and that one of them occupies the place of the maker, the other that of the matter.
     From: report of Parmenides (fragments/reports [c.474 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Pa.2
26. Natural Theory / A. Speculations on Nature / 7. Later Matter Theories / c. Matter as extension
Locke's solidity is not matter, because that is impenetrability and hardness combined [Robinson,H]
     Full Idea: Notoriously, Locke's filler for Descartes's geometrical matter, solidity, will not do, for that quality collapses on examination into a composite of the dispositional-cum-relational propery of impenetrability, and the secondary quality of hardness.
     From: Howard Robinson (Perception [1994], IX.3)
     A reaction: I would have thought the problem was that 'matter is solidity' turns out on analysis to be a tautology. We have a handful of nearly synonymous words for matter and our experiences of it, but they boil down to some 'given' thing for which we lack words.
27. Natural Reality / A. Classical Physics / 1. Mechanics / a. Explaining movement
It is feeble-minded to look for explanations of everything being at rest [Aristotle on Parmenides]
     Full Idea: For people to ignore the evidence of their senses and look for an explanation for everything being at rest is feeble-minded.
     From: comment on Parmenides (fragments/reports [c.474 BCE]) by Aristotle - Physics 253a32
     A reaction: Not exactly an argument, but an interestingly robust assertion of commonsense against dodgy arguments. Aristotle is not exactly an empiricist, but he is on that side of the fence.
27. Natural Reality / C. Space / 1. Void
The void can't exist, and without the void there can't be movement or separation [Parmenides, by Aristotle]
     Full Idea: Some philosophers thought what is must be one and immovable. The void, they say, is not: but unless there is a void what is cannot be moved, nor can it be many, since there is nothing to keep things apart.
     From: report of Parmenides (fragments/reports [c.474 BCE]) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 325a06
     A reaction: Somehow this doesn't seem very persuasive any more! I suppose we would distinguish various degrees of void, and assert the existence of sufficient void to allow movement and separation. We must surely agree that total nothingness doesn't exist.
27. Natural Reality / D. Time / 3. Parts of Time / a. Beginning of time
What could have triggered the beginning [of time and being]? [Parmenides]
     Full Idea: What need would have aroused it later or sooner, starting from nothing to come into being?
     From: Parmenides (fragments/reports [c.474 BCE]), quoted by Robin Le Poidevin - Travels in Four Dimensions 02 'Everything'
     A reaction: [Barnes 1982:178] This remains an excellent question. The last I heard was a 'quantum fluctuation', but that seems to be an event, which therefore needs time.
27. Natural Reality / E. Cosmology / 1. Cosmology
He was the first to discover the identity of the Morning and Evening Stars [Parmenides, by Diog. Laertius]
     Full Idea: He appears to have been the first to discover that Hesperus and Lucifer were the same star.
     From: report of Parmenides (fragments/reports [c.474 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Pa.3
     A reaction: This is the famous example used by Frege to discuss reference and meaning.
He was the first person to say the earth is spherical [Parmenides, by Diog. Laertius]
     Full Idea: He was the first person who asserted that the earth was of a spherical form.
     From: report of Parmenides (fragments/reports [c.474 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Pa.2