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All the ideas for 'Categories', 'Concluding Unscientific Postscript' and 'Grundgesetze der Arithmetik 2 (Basic Laws)'

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68 ideas

1. Philosophy / D. Nature of Philosophy / 2. Invocation to Philosophy
Without extensive examination firm statements are hard, but studying the difficulties is profitable [Aristotle]
     Full Idea: It is hard to make firm statements on these questions without having examined them many times, but to have gone through the various difficulties is not unprofitable.
     From: Aristotle (Categories [c.331 BCE], 08b23)
     A reaction: Suggesting that philosophy is more like drawing the map than completing the journey.
1. Philosophy / D. Nature of Philosophy / 5. Aims of Philosophy / d. Philosophy as puzzles
I conceived it my task to create difficulties everywhere [Kierkegaard]
     Full Idea: I conceived it my task to create difficulties everywhere.
     From: Søren Kierkegaard (Concluding Unscientific Postscript [1846], 'Author')
     A reaction: Nice. It is like Socrates's image of himself as the 'gadfly' of Athens. The interesting question is always to see what the rest of society makes of having someone in their midst who sees it as their social role to 'create difficulties'.
1. Philosophy / D. Nature of Philosophy / 8. Humour
Wherever there is painless contradiction there is also comedy [Kierkegaard]
     Full Idea: Wherever there is contradiction, the comical is also present. ...The tragic is the suffering contradiction, the comical is the painless contradiction.
     From: Søren Kierkegaard (Concluding Unscientific Postscript [1846], p.459), quoted by Terry Pinkard - German Philosophy 1760-1860 13
     A reaction: He is not saying that this is the only source of comedy. I once heard an adult say that there is one thing that is always funny, and that is a fart.
2. Reason / B. Laws of Thought / 4. Contraries
The contrary of good is bad, but the contrary of bad is either good or another evil [Aristotle]
     Full Idea: What is contrary to a good thing is necessarily bad, as we see with health and sickness. But the contrary of bad is sometimes good, sometimes not, as we see with excess, opposed by both deficiency and moderation.
     From: Aristotle (Categories [c.331 BCE], 13b36)
Both sides of contraries need not exist (as health without sickness, white without black) [Aristotle]
     Full Idea: With contraries it is not necessary if one exists for the other to exist too, for if everyone were well health would exist but not sickness, and if everything were white whiteness would exist but not black.
     From: Aristotle (Categories [c.331 BCE], 14a06)
2. Reason / D. Definition / 2. Aims of Definition
Later Frege held that definitions must fix a function's value for every possible argument [Frege, by Wright,C]
     Full Idea: Frege later became fastidious about definitions, and demanded that they must provide for every possible case, and that no function is properly determined unless its value is fixed for every conceivable object as argument.
     From: report of Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903]) by Crispin Wright - Frege's Concept of Numbers as Objects 3.xiv
     A reaction: Presumably definitions come in degrees of completeness, but it seems harsh to describe a desire for the perfect definition as 'fastidious', especially if we are talking about mathematics, rather than defining 'happiness'.
2. Reason / D. Definition / 7. Contextual Definition
We can't define a word by defining an expression containing it, as the remaining parts are a problem [Frege]
     Full Idea: Given the reference (bedeutung) of an expression and a part of it, obviously the reference of the remaining part is not always determined. So we may not define a symbol or word by defining an expression in which it occurs, whose remaining parts are known
     From: Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903], §66)
     A reaction: Dummett cites this as Frege's rejection of contextual definitions, which he had employed in the Grundlagen. I take it not so much that they are wrong, as that Frege decided to set the bar a bit higher.
2. Reason / D. Definition / 11. Ostensive Definition
Only what is logically complex can be defined; what is simple must be pointed to [Frege]
     Full Idea: Only what is logically complex can be defined; what is simple can only be pointed to.
     From: Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903], §180), quoted by Harold Hodes - Logicism and Ontological Commits. of Arithmetic p.137
     A reaction: Frege presumably has in mind his treasured abstract objects, such as cardinal numbers. It is hard to see how you could 'point to' anything in the phenomenal world that had atomic simplicity. Hodes calls this a 'desperate Kantian move'.
2. Reason / F. Fallacies / 8. Category Mistake / a. Category mistakes
The differentiae of genera which are different are themselves different in kind [Aristotle]
     Full Idea: The differentiae of genera which are different and not subordinate one to the other are themselves different in kind.
     From: Aristotle (Categories [c.331 BCE], 01b16)
     A reaction: This seems to be indicating a category mistake, as he warns us not to attribute the wrong kind of differentiae to something we are picking out.
3. Truth / A. Truth Problems / 2. Defining Truth
Kierkegaard's truth draws on authenticity, fidelity and honesty [Kierkegaard, by Carlisle]
     Full Idea: Kierkegaard offers a different interpretation of truth, which draws on the notions of authenticity, fidelity and honesty.
     From: report of Søren Kierkegaard (Concluding Unscientific Postscript [1846]) by Clare Carlisle - Kierkegaard: a guide for the perplexed 4
     A reaction: This notion of truth, meaning 'the real thing' (as in 'she was a true scholar'), seems to begin with Hegel. I suggest we use the word 'genuine' for that, and save 'truth' for its traditional role. It is disastrous to blur the simple concept of truth.
3. Truth / A. Truth Problems / 3. Value of Truth
Pure truth is for infinite beings only; I prefer endless striving for truth [Kierkegaard]
     Full Idea: If God held all truth enclosed in his right hand, and in his left hand the ever-striving drive for truth, even if erring forever, and he were to say Choose! I would humbly fall at his left hand and say Father, give! Pure truth is for infinite beings only.
     From: Søren Kierkegaard (Concluding Unscientific Postscript [1846], p.106)
     A reaction: A sobering realistic thought of our own limitations; Kierkegaard allows that there is no limit to how far we can strive for truth. Just that truth is comprehended by infinite beings (if any), not by mere mortals. [SY]
3. Truth / A. Truth Problems / 8. Subjective Truth
The highest truth we can get is uncertainty held fast by an inward passion [Kierkegaard]
     Full Idea: An objective uncertainty held fast in an appropriation-process of the most passionate inwardness is the truth, the highest truth available for an existing individual.
     From: Søren Kierkegaard (Concluding Unscientific Postscript [1846])
     A reaction: [Bk 711] Offered as a definition of truth, knowing how strange and paradoxical it sounds. If we view all life as subjectivity, then there can of course be nothing more to truth than passionate conviction. Personally I think thought can be objective.
3. Truth / B. Truthmakers / 5. What Makes Truths / b. Objects make truths
A true existence statement has its truth caused by the existence of the thing [Aristotle]
     Full Idea: Whereas the true statement [that there is a man] is in no way the cause of the actual thing's existence, the actual thing does seem in some way the cause of the statement's being true.
     From: Aristotle (Categories [c.331 BCE], 14b18)
     A reaction: Armstrong offers this as the earliest statement of the truthmaker principle. Notice the cautious qualification 'seem in some way'. The truthmaker dependence seems even clearer in falsemaking, where the death of the man falsifies the statement.
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Predications of predicates are predications of their subjects [Aristotle]
     Full Idea: Whenever one thing is predicated of another as of a subject, all things said of what is predicated will be said of the subject also.
     From: Aristotle (Categories [c.331 BCE], 01b10)
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
Cardinals say how many, and reals give measurements compared to a unit quantity [Frege]
     Full Idea: The cardinals and the reals are completely disjoint domains. The cardinal numbers answer the question 'How many objects of a given kind are there?', but the real numbers are for measurement, saying how large a quantity is compared to a unit quantity.
     From: Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903], §157), quoted by Michael Dummett - Frege philosophy of mathematics Ch.19
     A reaction: We might say that cardinals are digital and reals are analogue. Frege is unusual in totally separating them. They map onto one another, after all. Cardinals look like special cases of reals. Reals are dreams about the gaps between cardinals.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / c. Priority of numbers
One is prior to two, because its existence is implied by two [Aristotle]
     Full Idea: One is prior to two because if there are two it follows at once that there is one, whereas if there is one there is not necessarily two.
     From: Aristotle (Categories [c.331 BCE], 14a29)
     A reaction: The axiomatic introduction of a 'successor' to a number does not seem to introduce this notion of priority, based on inclusiveness. Introducing order by '>' also does not seem to indicate any logical priority.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
Parts of a line join at a point, so it is continuous [Aristotle]
     Full Idea: A line is a continuous quantity. For it is possible to find a common boundary at which its parts join together, a point.
     From: Aristotle (Categories [c.331 BCE], 04b33)
     A reaction: This appears to be the essential concept of a Dedekind cut. It seems to be an open question whether a cut defines a unique number, but a boundary seems to be intrinsically unique. Aristotle wins again.
Real numbers are ratios of quantities [Frege, by Dummett]
     Full Idea: Frege fixed on construing real numbers as ratios of quantities (in agreement with Newton).
     From: report of Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903]) by Michael Dummett - Frege philosophy of mathematics Ch.20
     A reaction: If 3/4 is the same real number as 6/8, which is the correct ratio? Why doesn't the square root of 9/16 also express it? Why should irrationals be so utterly different from rationals? In what sense are they both 'numbers'?
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / b. Greek arithmetic
Some quantities are discrete, like number, and others continuous, like lines, time and space [Aristotle]
     Full Idea: Of quantities, some are discrete, others continuous. ...Discrete are number and language; continuous are lines, surfaces, bodies, and also, besides these, time and place.
     From: Aristotle (Categories [c.331 BCE], 04b20)
     A reaction: This distinction seems to me to be extremely illuminating, when comparing natural numbers with real numbers, and it is the foundation of the Greek view of mathematics.
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / c. Fregean numbers
Frege's biggest error is in not accounting for the senses of number terms [Hodes on Frege]
     Full Idea: The inconsistency of Grundgesetze was only a minor flaw. Its fundamental flaw was its inability to account for the way in which the senses of number terms are determined. It leaves the reference-magnetic nature of the standard numberer a mystery.
     From: comment on Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903]) by Harold Hodes - Logicism and Ontological Commits. of Arithmetic p.139
     A reaction: A point also made by Hofweber. As a logician, Frege was only concerned with the inferential role of number terms, and he felt he had captured their logical form, but it is when you come to look at numbers in natural language that he seem in trouble.
A number is a class of classes of the same cardinality [Frege, by Dummett]
     Full Idea: For Frege, in 'Grundgesetze', a number is a class of classes of the same cardinality.
     From: report of Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903]) by Michael Dummett - Frege Philosophy of Language (2nd ed) Ch.14
6. Mathematics / C. Sources of Mathematics / 7. Formalism
Formalism misunderstands applications, metatheory, and infinity [Frege, by Dummett]
     Full Idea: Frege's three main objections to radical formalism are that it cannot account for the application of mathematics, that it confuses a formal theory with its metatheory, and it cannot explain an infinite sequence.
     From: report of Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903], §86-137) by Michael Dummett - Frege philosophy of mathematics
     A reaction: The application is because we don't design maths randomly, but to be useful. The third objection might be dealt with by potential infinities (from formal rules). The second objection sounds promising.
Only applicability raises arithmetic from a game to a science [Frege]
     Full Idea: It is applicability alone which elevates arithmetic from a game to the rank of a science.
     From: Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903], §91), quoted by Stewart Shapiro - Thinking About Mathematics 6.1.2
     A reaction: This is the basic objection to Formalism. It invites the question of why it is applicable, which platonists like Frege don't seem to answer (though Plato himself has reality modelled on the Forms). This is why I like structuralism.
7. Existence / A. Nature of Existence / 3. Being / f. Primary being
Primary being must be more than mere indeterminate ultimate subject of predication [Politis on Aristotle]
     Full Idea: He criticises his 'Categories' view, because if primary being is simply the ultimate subject of predication the primary being is, in virtue of itself, something indeterminate; it would be a necessary but not a sufficient condition for primary being.
     From: comment on Aristotle (Categories [c.331 BCE]) by Vassilis Politis - Aristotle and the Metaphysics 7.5
     A reaction: Thus, Politis argues, primary being is essence in the later work. The words 'substance' and 'ousia' cause confusion here, and must be watched closely. Wedin argues that Aristotle merely develops his 'Categories' view, but most disagree.
7. Existence / B. Change in Existence / 1. Nature of Change
There are six kinds of change: generation, destruction, increase, diminution, alteration, change of place [Aristotle]
     Full Idea: There are six kinds of change: generation, destruction, increase, diminution, alteration, change of place. A change in our affections would be an example of alteration.
     From: Aristotle (Categories [c.331 BCE], 15a13)
7. Existence / C. Structure of Existence / 4. Ontological Dependence
A thing is prior to another if it implies its existence [Aristotle]
     Full Idea: That from which the implication of existence does not hold reciprocally is thought to be prior.
     From: Aristotle (Categories [c.331 BCE], 14a32)
     A reaction: shadows and objects
Of interdependent things, the prior one causes the other's existence [Aristotle]
     Full Idea: For of things which reciprocate as to implication of existence, that which is in some way the cause of the other's existence might reasonably by called prior by nature.
     From: Aristotle (Categories [c.331 BCE], 14b12)
     A reaction: Not so clear when you seek examples. The bus is prior to its redness, but you can't have a colourless bus, so being coloured is prior to being a bus. Aristotle's example is a man being prior to the truths about him.
7. Existence / E. Categories / 3. Proposed Categories
The categories (substance, quality, quantity, relation, action, passion, place, time) peter out inconsequentially [Benardete,JA on Aristotle]
     Full Idea: The Aristotelian schedule of categories - substance, quality, quantity, relation, action, passion, place, time, and so forth - appears to peter out inconsequentially.
     From: comment on Aristotle (Categories [c.331 BCE]) by José A. Benardete - Metaphysics: the logical approach Ch.7
     A reaction: Compare Idea 5544 for Kant's attempt to classify categories. Personally I like the way Aristotle's 'peter out'. That seems to me a more plausible character for good metaphysics.
There are ten basic categories for thinking about things [Aristotle]
     Full Idea: Of things said without any combination, each signifies either substance or quantity or qualification or a relative or where or when or being-in-a-position or having or doing or being-affected.
     From: Aristotle (Categories [c.331 BCE], 01b25)
     A reaction: This sums up the earlier of Aristotle's two metaphysical view, and each of this categories is discussed in the present text.
Substance,Quantity,Quality,Relation,Place,Time,Being-in-a-position,Having,Doing,Being affected [Aristotle, by Westerhoff]
     Full Idea: Aristotle's list of ten categories proved to be the most influential scheme found in his works: Substance, Quantity, Quality, Relation, Place, Time, Being-in-a-position, Having, Doing, Being affected.
     From: report of Aristotle (Categories [c.331 BCE]) by Jan Westerhoff - Ontological Categories §01
7. Existence / E. Categories / 4. Category Realism
Aristotle derived categories as answers to basic questions about nature, size, quality, location etc. [Aristotle, by Gill,ML]
     Full Idea: Aristotle seems to have worked out his list of categories by considering various questions that one might ask about a particular object, such as What is it? How big is it? How is it qualified? And Where is it?
     From: report of Aristotle (Categories [c.331 BCE]) by Mary Louise Gill - Aristotle on Substance
     A reaction: Of course, to think of his questions, Aristotle already had categories in his mind. How would he approach a proposal to recategorise reality more efficiently?
8. Modes of Existence / A. Relations / 1. Nature of Relations
Aristotle said relations are not substances, so (if they exist) they must be accidents [Aristotle, by Heil]
     Full Idea: Aristotle categorised relations as accidents - Socrates's whiteness, the sphericity of this ball - entities dependent on substances. Relations are not substances, so they must be, if anything at all, accidents.
     From: report of Aristotle (Categories [c.331 BCE], §7) by John Heil - Relations 'Historical'
     A reaction: Heil says this thought encouraged anti-realist views of relations, which became the norm until Russell.
8. Modes of Existence / B. Properties / 2. Need for Properties
Aristotle promoted the importance of properties and objects (rather than general and particular) [Aristotle, by Frede,M]
     Full Idea: In 'Categories' Aristotle is taking a first step in making the distinction between objects and properties central to ontology. This plays virtually no role in Plato, and was overshadowed by the distinction between general and particular.
     From: report of Aristotle (Categories [c.331 BCE]) by Michael Frede - Individuals in Aristotle I
     A reaction: Frede says he gets in a tangle because he mixes the earlier and the new views. Because we are nowadays in a total muddle about properties, I'm thinking we should go back to the earlier view! Modern commentators make him a trope theorist.
8. Modes of Existence / B. Properties / 6. Categorical Properties
Some things said 'of' a subject are not 'in' the subject [Aristotle]
     Full Idea: Of things there are, some are said of a subject, but are not in any subject. For example, man is said of a subject, the individual man, but is not in any subject.
     From: Aristotle (Categories [c.331 BCE], 01a20)
     A reaction: See? 'Being a man' is not a property of a man! Only the properties which are 'in' the man are properties of the man. The rest are things which are said 'of' men, usually as classifications. A classification is not a property.
We call them secondary 'substances' because they reveal the primary substances [Aristotle]
     Full Idea: It is reasonable that, after the primary substances, their species and genera should be the only other things called (secondary) substances. For only they, of things predicated, reveal the primary substance.
     From: Aristotle (Categories [c.331 BCE], 02b29)
     A reaction: This is the key passage in all of Aristotle for sortal essentialists like Wiggins, especially the word 'only'. I take it that this observation is superseded by the Metaphysics. Definition is the route to substance (which involves general terms).
8. Modes of Existence / B. Properties / 9. Qualities
Four species of quality: states, capacities, affects, and forms [Aristotle, by Pasnau]
     Full Idea: In Categories 8 there are four species of qualities: States and conditions, Natural capacities and incapacities, Affective qualities or affections, and Shape and external form.
     From: report of Aristotle (Categories [c.331 BCE], Ch.8) by Robert Pasnau - Metaphysical Themes 1274-1671 23.5
8. Modes of Existence / D. Universals / 3. Instantiated Universals
Colour must be in an individual body, or it is not embodied [Aristotle]
     Full Idea: Colour is in body and therefore also in an individual body; for were it not in some individual body it would not be in body at all.
     From: Aristotle (Categories [c.331 BCE], 02b02)
     A reaction: This may be just a truism, or it may be the Aristotelian commitment to universals only existing if they are instantiated.
9. Objects / A. Existence of Objects / 1. Physical Objects
Aristotle gave up his earlier notion of individuals, because it relied on universals [Aristotle, by Frede,M]
     Full Idea: In 'Metaphysics' Aristotle abandons the notion of an individual which he had relied on in the 'Categories', since it presupposes that there are general things, that there are universals.
     From: report of Aristotle (Categories [c.331 BCE]) by Michael Frede - Individuals in Aristotle Intro
     A reaction: Ah, very illuminating. So all the way through we have a concept of individuals, first relying on universals, and then relying on hylomorphism? I suppose a bundle theory of individuals would need universals.
9. Objects / A. Existence of Objects / 5. Individuation / e. Individuation by kind
Genus and species are substances, because only they reveal the primary substance [Aristotle, by Wedin]
     Full Idea: The reason Aristotle gives for calling species and genera substances is that of what is predicated only they reveal what the primary substance is.
     From: report of Aristotle (Categories [c.331 BCE], 02b29-37) by Michael V. Wedin - Aristotle's Theory of Substance III.6
     A reaction: Thus we should not be misled into thinking that the genus and species ARE the essence. We edge our way towards the essence of an individual by subdividing its categories.
9. Objects / B. Unity of Objects / 2. Substance / a. Substance
Substances have no opposites, and don't come in degrees (including if the substance is a man) [Aristotle]
     Full Idea: There is nothing contrary to substances,…. and a substance does not admit of a more and a less. If this substance is a man, it will not be more a man or less a man either than itself or than another man.
     From: Aristotle (Categories [c.331 BCE], 03b33)
Is primary substance just an ultimate subject, or some aspect of a complex body? [Aristotle, by Gill,ML]
     Full Idea: 'Categories' treats something's being an ultimate subject as a test for being a primary substance, but it does not treat its primary objects as complex bodies consisting of matter and form. In that case, is the composite or a feature the ultimate subject?
     From: report of Aristotle (Categories [c.331 BCE]) by Mary Louise Gill - Aristotle on Substance Ch.1
     A reaction: Gill is trying to throw light on the difference between 'Categories' and 'Metaphysics'. Once you have hylomorphism (form-plus-matter) you have a new difficulty in explaining unity. The answer is revealed once we understand 'form'.
Primary being is 'that which lies under', or 'particular substance' [Aristotle, by Politis]
     Full Idea: In 'Categories' Aristotle argues the primary being (proté ousia) is the ultimate subject of predication (to hupokeimenon, meaning 'that which lies under'), nowadays referred to as the 'particular substance' view.
     From: report of Aristotle (Categories [c.331 BCE]) by Vassilis Politis - Aristotle and the Metaphysics 4.4
     A reaction: Politis says that Aristotle shifts to the quite different view in 'Metaphysics', that primary being is essence, rather than mere subject of predication.
A single substance can receive contrary properties [Aristotle]
     Full Idea: It seems distinctive of substance that what is numerically one and the same is able to receive contraries. ...For example, an individual man - one and the same - becomes pale at one time and dark at another.
     From: Aristotle (Categories [c.331 BCE], 04a10/20)
9. Objects / B. Unity of Objects / 2. Substance / c. Types of substance
Secondary substances do have subjects, so they are not ultimate in the ontology [Aristotle, by Frede,M]
     Full Idea: The concept of substance applies to secondary substances only with some deletions; ..it is not true that they have no subjects, and hence they are not ultimate subjects for all other elements of the ontology.
     From: report of Aristotle (Categories [c.331 BCE]) by Michael Frede - Title, Unity, Authenticity of the 'Categories' V
     A reaction: It increasingly strikes that to treat secondary substance (roughly, species) as essence is a shocking misreading of Aristotle. Frede says they are substances, because they do indeed 'underlie'.
In earlier Aristotle the substances were particulars, not kinds [Aristotle, by Lawson-Tancred]
     Full Idea: In 'Metaphysics' Aristotle changed his view, as in 'Categories' the substances, the basic realities, were particular items, notably individual men, horses, cabbages etc.
     From: report of Aristotle (Categories [c.331 BCE]) by Hugh Lawson-Tancred - Introductions to 'Metaphysics' p.178
     A reaction: The charge is that having successfully rebelled against Plato, Aristotle gradually succumbed to his teacher's influence, and ended up with a more platonist view. For anti-platonists like myself, the 'Categories' seems to be the key text.
A 'primary' substance is in each subject, with species or genera as 'secondary' substances [Aristotle]
     Full Idea: A substance, in its most primary sense, is that which is neither said of a subject nor in a subject, e.g. the individual man or horse. The species in which things primarily called substances are, are called secondary substances, as are the genera.
     From: Aristotle (Categories [c.331 BCE], 02a11)
     A reaction: This distinction between 'primary' and 'secondary' substances is characteristic of Aristotle's earlier metaphysical view, with the later view (more unified and Platonic) in the 'Metaphysics'.
9. Objects / B. Unity of Objects / 2. Substance / d. Substance defined
Earlier Aristotle had objects as primary substances, but later he switched to substantial form [Aristotle, by Lowe]
     Full Idea: In 'Categories' primary substances are individual concrete objects, such as a particular horse, whereas in 'Metaphysics' such things are combinations of matter and substantial form, with the latter being the primary substances.
     From: report of Aristotle (Categories [c.331 BCE]) by E.J. Lowe - The Possibility of Metaphysics 9.1
     A reaction: Lowe claims there is no real difference. Aristotle came to think that matter was not part of primary substance, so the shift seems to be that substance was concrete, but then he decided it was abstract. Physicists will prefer 'Metaphysics'.
Things are called 'substances' because they are subjects for everything else [Aristotle]
     Full Idea: It is because the primary substances are subjects for everything else that they are called substances [ousiai] most strictly.
     From: Aristotle (Categories [c.331 BCE], 03a04)
     A reaction: This points to a rather minimal account of substance, as possibly the 'bare particular' which has no other role than to have properties. This expands in 'Metaphysics' to be matter which has form, making properties possible.
9. Objects / B. Unity of Objects / 3. Unity Problems / e. Vague objects
The first demand of logic is of a sharp boundary [Frege]
     Full Idea: The first demand of logic is of a sharp boundary.
     From: Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903], §160), quoted by Michael Dummett - Frege philosophy of mathematics Ch.22
     A reaction: Nothing I have read about vagueness has made me doubt Frege's view of this, although precisification might allow you to do logic with vague concepts without having to finally settle where the actual boundaries are.
9. Objects / D. Essence of Objects / 3. Individual Essences
A primary substance reveals a 'this', which is an individual unit [Aristotle]
     Full Idea: Every substance seems to signify a certain 'this'. As regards the primary substances, it is indisputably true that each of them signifies a certain 'this'; for the thing revealed is individual and numerically one.
     From: Aristotle (Categories [c.331 BCE], 03b10)
     A reaction: The notion of 'primary' substance is confined to this earlier metaphysics of Aristotle.
9. Objects / D. Essence of Objects / 8. Essence as Explanatory
Primary substances are ontological in 'Categories', and explanatory in 'Metaphysics' [Aristotle, by Wedin]
     Full Idea: The primacy of 'Categories' primary substances is a kind of ontological primacy, whereas the primacy of form is a kind of structural or explanatory primacy.
     From: report of Aristotle (Categories [c.331 BCE]) by Michael V. Wedin - Aristotle's Theory of Substance X.9
     A reaction: 'Structural' and 'explanatory' sound very different, since the former sounds ontological and the latter epistemological (and more subjective).
9. Objects / F. Identity among Objects / 5. Self-Identity
Aristotle denigrates the category of relation, but for modern absolutists self-relation is basic [Benardete,JA on Aristotle]
     Full Idea: Aristotle denigrates the whole category of relations, but modern logical absolutists single out self-relation (in the mode of identity) as metaphysically privileged.
     From: comment on Aristotle (Categories [c.331 BCE]) by José A. Benardete - Metaphysics: the logical approach Ch.8
     A reaction: I think this refers to Plantinga and Merrihew Adams, who make identity-with-itself the basic component of individual existences.
16. Persons / B. Nature of the Self / 2. Ethical Self
The real subject is ethical, not cognitive [Kierkegaard]
     Full Idea: The real subject is not the cognitive subject …the real subject is the ethically existing subject.
     From: Søren Kierkegaard (Concluding Unscientific Postscript [1846], p.281), quoted by Kevin Aho - Existentialism: an introduction 2 'Subjective'
     A reaction: Perhaps we should say the essence of the self is its drive to live, not its drive to know. Just getting through the day is top priority, and ethics don’t figure much for the solitary person. But each activity, such as cooking, has its virtues.
18. Thought / E. Abstraction / 3. Abstracta by Ignoring
The modern account of real numbers detaches a ratio from its geometrical origins [Frege]
     Full Idea: From geometry we retain the interpretation of a real number as a ratio of quantities or measurement-number; but in more recent times we detach it from geometrical quantities, and from all particular types of quantity.
     From: Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903], §159), quoted by Michael Dummett - Frege philosophy of mathematics
     A reaction: Dummett glosses the 'recent' version as by Cantor and Dedekind in 1872. This use of 'detach' seems to me startlingly like the sort of psychological abstractionism which Frege was so desperate to avoid.
18. Thought / E. Abstraction / 8. Abstractionism Critique
If we abstract the difference between two houses, they don't become the same house [Frege]
     Full Idea: If abstracting from the difference between my house and my neighbour's, I were to regard both houses as mine, the defect of the abstraction would soon be made clear. It may, though, be possible to obtain a concept by means of abstraction...
     From: Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903], §99)
     A reaction: Note the important concession at the end, which shows Frege could never deny the abstraction process, despite all the modern protests by Geach and Dummett that he totally rejected it.
19. Language / C. Assigning Meanings / 3. Predicates
Only what can be said of many things is a predicable [Aristotle, by Wedin]
     Full Idea: Aristotle reminds us that nothing is to count as predicable that cannot be said-of many things.
     From: report of Aristotle (Categories [c.331 BCE]) by Michael V. Wedin - Aristotle's Theory of Substance III.1
     A reaction: Thus there wouldn't be any predicates if there were not universals. Could we have proper names for individual qualities (tropes), in the way that we have them for individual objects?
Some predicates signify qualification of a substance, others the substance itself [Aristotle]
     Full Idea: 'White' signifies nothing but a qualification, whereas the species ('man') and the genus ('animal') mark off the qualification of substance - they signify substance of a certain qualification.
     From: Aristotle (Categories [c.331 BCE], 03b18)
     A reaction: This is making a fundamental distinction between two different types of predication. I would describe them as one attributing a real property, and the other attributing a category (as a result of the properties). I don't think 'substance' helps here.
23. Ethics / F. Existentialism / 1. Existentialism
While big metaphysics is complete without ethics, personal philosophy emphasises ethics [Kierkegaard]
     Full Idea: While the Hegelian philosophy goes on and is finished without having an Ethics, the more simple philosophy which is propounded by an existing individual for existing individuals, will more especially emphasis the ethical.
     From: Søren Kierkegaard (Concluding Unscientific Postscript [1846], 'Lessing')
     A reaction: This is reminiscent of the Socratic revolution, which shifted philosophy from the study of nature to the study of personal virtue. However, if we look for ethical teachings in existentialism, there often seems to be a black hole in the middle.
Speculative philosophy loses the individual in a vast vision of humanity [Kierkegaard]
     Full Idea: Being an individual man is a thing that has been abolished, and every speculative philosopher confuses himself with humanity at large, whereby he becomes infinitely great - and at the same time nothing at all.
     From: Søren Kierkegaard (Concluding Unscientific Postscript [1846], 'Lessing')
     A reaction: Compare Idea 4840. This is a beautiful statement of the motivation for existentialism. The sort of philosophers who love mathematics (Plato, Descartes, Leibniz, Russell) love losing themselves in abstractions. This is the rebellion.
23. Ethics / F. Existentialism / 6. Authentic Self
People want to lose themselves in movements and history, instead of being individuals [Kierkegaard]
     Full Idea: Everything must attach itself so as to be part of some movement; men are determined to lose themselves in the totality of things, in world-history, fascinated and deceived by a magic witchery; no one wants to be an individual human being.
     From: Søren Kierkegaard (Concluding Unscientific Postscript [1846])
     A reaction: [Bk 711] I presume 'world-history' refers to the exhilerating ideas of Hegel. Right now [2017] I would say we have far too much of people only wanting to be individuals, with insufficient attention to our social nature.
Becoming what one is is a huge difficulty, because we strongly aspire to be something else [Kierkegaard]
     Full Idea: Striving to become what one already is is a very difficult task, the most difficult of all, because every human being has a strong natural bent and passion to become something more and different.
     From: Søren Kierkegaard (Concluding Unscientific Postscript [1846], 'Subjective')
     A reaction: Presumably most people continually drift between vanity and low self-esteem, and between unattainable daydreams and powerless immediate reality. That creates the stage on which Kierkegaard's interesting battle would have to be fought.
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / b. Scientific necessity
It is not possible for fire to be cold or snow black [Aristotle]
     Full Idea: It is not possible for fire to be cold or snow black.
     From: Aristotle (Categories [c.331 BCE], 12b01)
27. Natural Reality / A. Classical Physics / 2. Thermodynamics / d. Entropy
Change goes from possession to loss (as in baldness), but not the other way round [Aristotle]
     Full Idea: Change occurs from possession to privation, but from privation to possession is impossible; one who has gone blind does not recover sight nor does a bald man regain his hair nor does a toothless man grow new ones.
     From: Aristotle (Categories [c.331 BCE], 13a35)
     A reaction: Although this seems like an insight into entropy, it isn't an accurate observation, since trees lose their leaves, and then regain them in spring. Maybe somewhere men regrow their hair each spring.
28. God / A. Divine Nature / 2. Divine Nature
God does not think or exist; God creates, and is eternal [Kierkegaard]
     Full Idea: God does not think, He creates; God does not exist, he is eternal.
     From: Søren Kierkegaard (Concluding Unscientific Postscript [1846], 'Thinker')
     A reaction: The sort of nicely challenging remarks we pay philosophers to come up with. I don't understand the second claim, but the first one certainly avoids all paradoxes that arise if God experiences all the intrinsic problems of thinking.
28. God / B. Proving God / 3. Proofs of Evidence / d. Religious Experience
God cannot be demonstrated objectively, because God is a subject, only existing inwardly [Kierkegaard]
     Full Idea: Choosing the objective way enters upon the entire approximation-process by which it is proposed to bring God to light objectively. But this is in all eternity impossible, because God is a subject, and therefore exist only for subjectivity in inwardness.
     From: Søren Kierkegaard (Concluding Unscientific Postscript [1846])
     A reaction: [pg in 711] This seems to have something like Wittgenstein's problem with a private language - that with no external peer-review it is unclear what the commitment is.
28. God / C. Attitudes to God / 2. Pantheism
Pantheism destroys the distinction between good and evil [Kierkegaard]
     Full Idea: So called pantheistic systems have often been characterised and challenged by the assertion that they abrogate the distinction between good and evil.
     From: Søren Kierkegaard (Concluding Unscientific Postscript [1846], 'Lessing')
     A reaction: He will have Spinoza in mind. Interesting. Obviously this criticism would come from someone who thought that the traditional deity was the only source of goodness. Good/evil isn't all-or-nothing. A monistic system could contain them.
29. Religion / D. Religious Issues / 1. Religious Commitment / e. Fideism
Faith is the highest passion in the sphere of human subjectivity [Kierkegaard]
     Full Idea: Faith is the highest passion in the sphere of human subjectivity.
     From: Søren Kierkegaard (Concluding Unscientific Postscript [1846], 'Subjective')
     A reaction: The word 'highest' should always ring alarm bells. The worst sort of religious fanatics seem to be in the grip of this 'high' passion. The early twenty-first century is an echo of eighteenth century England, with its dislike of religious 'enthusiasm'.
Without risk there is no faith [Kierkegaard]
     Full Idea: Without risk there is no faith.
     From: Søren Kierkegaard (Concluding Unscientific Postscript [1846], 'Inwardness')
     A reaction: Remarks like this make you realise that Kierkegaard is just as much of a romantic as most of the other nineteenth century philosophers. Plunge into the dark unknown of the human psyche, in order to intensify and heighten human life.