Combining Philosophers

Ideas for Hermarchus, Harry G. Frankfurt and Aristotle

unexpand these ideas     |    start again     |     choose another area for these philosophers

display all the ideas for this combination of philosophers


72 ideas

2. Reason / A. Nature of Reason / 1. On Reason
Desired responsible actions result either from rational or from irrational desire [Aristotle]
     Full Idea: And of responsible actions, some are done through habit, some through desire, and of these some through rational and some through irrational desire.
     From: Aristotle (The Art of Rhetoric [c.350 BCE], 1369a01)
     A reaction: Identified by Michael Frede, to illustrate reason having its own distinctive type of desire ('Boulesis'). I suspect that the rational desires are the morally good desires.
Didactic argument starts from the principles of the subject, not from the opinions of the learner [Aristotle]
     Full Idea: Didactic arguments are those which reason from the principles appropriate to each branch of learning and not from the opinions of the answerer (for he who is learning must take things on trust).
     From: Aristotle (Sophistical Refutations [c.331 BCE], 165b01)
There is pure deductive reasoning, and explanatory demonstration reasoning [Aristotle, by Politis]
     Full Idea: Aristotle distinguishes between deductive reasoning (sullogismos) and demonstration (apodeixis). All demonstration is deductive reasoning, but not all deductive reasoning is demonstration.
     From: report of Aristotle (Posterior Analytics [c.327 BCE], Bk I.2) by Vassilis Politis - Aristotle and the Metaphysics 5.3
     A reaction: This sounds not far off the distinction between single-turnstile (formal proof) and double-turnstile (semantic consequence). Politis says, though, that the key point is the demonstration is explanatory.
2. Reason / A. Nature of Reason / 2. Logos
Human beings, alone of the animals, have logos [Aristotle]
     Full Idea: Human beings, alone of the animals, have logos.
     From: Aristotle (Politics [c.332 BCE], 1253a09)
     A reaction: This may be a grand claim that we are the only animals that can think rationally, or a more obvious observation that we are the only ones that talk. Aristotle was well aware that logos is a very resonant word.
An account is either a definition or a demonstration [Aristotle]
     Full Idea: Every account is either a definition or a demonstration.
     From: Aristotle (De Anima [c.329 BCE], 407a24)
     A reaction: That is, it is either a summary of the thing's essential nature, or it is a proof of some natural fact, starting from first principles.
For Aristotle logos is essentially the ability to talk rationally about questions of value [Roochnik on Aristotle]
     Full Idea: For Aristotle logos is the ability to speak rationally about, with the hope of attaining knowledge, questions of value.
     From: comment on Aristotle (works [c.330 BCE]) by David Roochnik - The Tragedy of Reason p.26
2. Reason / A. Nature of Reason / 4. Aims of Reason
Reasoning distinguishes what is beneficial, and hence what is right [Aristotle]
     Full Idea: Logos is for the purpose of clarifying the beneficial and the harmful and as a result the right and the wrong.
     From: Aristotle (Politics [c.332 BCE], 1253a12)
     A reaction: I don't think this is asserting that reason can perceive values. Logos perceives the essential nature (and hence purpose) of each thing (including people), which indicates which are its good and bad states.
Aristotle is the supreme optimist about the ability of logos to explain nature [Roochnik on Aristotle]
     Full Idea: Aristotle is the great theoretician who articulates a vision of a world in which natural and stable structures can be rationally discovered. His is the most optimistic and richest view of the possibilities of logos
     From: comment on Aristotle (works [c.330 BCE]) by David Roochnik - The Tragedy of Reason p.95
Reason grasps generalities, while the senses grasp particulars [Aristotle]
     Full Idea: Reason grasps generalities, while the senses grasp particulars.
     From: Aristotle (Physics [c.337 BCE], 189a06)
     A reaction: This does not seem to be entirely true. Sherlock Holmes reasons towards the particular. Nevertheless, we see what he means. Reason deals with universals, and reason derives principles and patterns from the particulars.
Reasoning is a way of making statements which makes them lead on to other statements [Aristotle]
     Full Idea: Reasoning is based on certain statements made in such a way as necessarily to cause the assertion of things other than those statements and as a result of those statements.
     From: Aristotle (Sophistical Refutations [c.331 BCE], 165a01)
2. Reason / A. Nature of Reason / 6. Coherence
Maybe everything could be demonstrated, if demonstration can be reciprocal or circular [Aristotle]
     Full Idea: Some optimists think understanding arises only through demonstration, but say there could be demonstration of everything, for it is possible to demonstrate in a circle or reciprocally.
     From: Aristotle (Posterior Analytics [c.327 BCE], 72b16)
     A reaction: I'm an optimist in this sense, though what is being described would probably best be called 'large-scale coherence'. Two reciprocal arguments look bad, but a hundred look good.
2. Reason / A. Nature of Reason / 7. Status of Reason
It is readily agreed that thinking is the most godlike of things in our experience [Aristotle]
     Full Idea: It is readily agreed that thinking is the most godlike of things in our experience.
     From: Aristotle (Metaphysics [c.324 BCE], 1074b11)
Intelligence which looks ahead is a natural master, while bodily strength is a natural slave [Aristotle]
     Full Idea: The element that can use its intelligence to look ahead is by nature ruler and master, while that which has the bodily strength to do the actual work is by nature a slave.
     From: Aristotle (Politics [c.332 BCE], 1252a30)
     A reaction: I claim that the two distinguishing features of humanity are prescience and meta-thought, so I can't really disagree with this.
2. Reason / A. Nature of Reason / 9. Limits of Reason
A very hungry man cannot choose between equidistant piles of food [Aristotle]
     Full Idea: The man who, though exceedingly hungry and thirsty, and both equally, yet being equidistant from food and drink, is therefore bound to stay where he is.
     From: Aristotle (On the Heavens [c.336 BCE], 296b33)
     A reaction: This is, of course, Buridan's famous Ass, but this quotation has the advantage of precedence, and also of being expressed in an original quotation (which does not exist for Buridan).
2. Reason / B. Laws of Thought / 3. Non-Contradiction
A thing cannot be both in and not-in the same thing (at a given time) [Aristotle]
     Full Idea: It is impossible for the same thing at the same time both to be-in and not to be-in the same thing in the same respect.
     From: Aristotle (Metaphysics [c.324 BCE], 1005b19)
     A reaction: Aristotle is really discussing non-contradiction here, but this formulation is very close to Leibniz's Law (that two identical things must have identical properties).
The most certain basic principle is that contradictories can't be true at the same time [Aristotle]
     Full Idea: The most certain of all basic principles is that contradictory propositions are not true at the same time.
     From: Aristotle (Metaphysics [c.324 BCE], 1011b13)
     A reaction: Principle of Noncontradiction
Aristotle does not take the principle of non-contradiction for granted [Aristotle, by Politis]
     Full Idea: Aristotle goes to great lengths to defend the principle of non-contradiction, and does not at all think that it is obviously true.
     From: report of Aristotle (Metaphysics [c.324 BCE], logic) by Vassilis Politis - Aristotle and the Metaphysics 5.1
Contrary statements can both be reasonable, if they are meant in two different ways [Aristotle]
     Full Idea: Contrary things can be reasonably held …because the contrary positions will stand if what is said is true in one way, but not true in another.
     From: Aristotle (Eudemian Ethics [c.333 BCE], 1235b17)
     A reaction: My strategy here is to clarify the unambiguous underlying propositions which are being expressed. There will then be either agreement, or flat contradiction.
We cannot say that one thing both is and is not a man [Aristotle]
     Full Idea: It is not possible to say truly at the same time that the same thing both is and is not a man.
     From: Aristotle (Metaphysics [c.324 BCE], 1006b33)
For Aristotle predication is regulated by Non-Contradiction, because underlying stability is essential [Roochnik on Aristotle]
     Full Idea: The Principle of Noncontradiction is for Aristotle the ultimate regulator of predication. In order for any predication to be significant it must refer to something definite and stable.
     From: comment on Aristotle (Metaphysics [c.324 BCE], 1011b13) by David Roochnik - The Tragedy of Reason p.152
2. Reason / B. Laws of Thought / 4. Contraries
Contraries are by definition as far distant as possible from one another [Aristotle]
     Full Idea: Contraries are by definition as far distant as possible from one another.
     From: Aristotle (Nicomachean Ethics [c.334 BCE], 1108b33)
     A reaction: A nice concept and definition. Note that it is being used about ethics (the mean), not just about pure logic or mathematics.
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)
In "Callias is just/not just/unjust", which of these are contraries? [Aristotle]
     Full Idea: Take, for example, "Callias is just", "Callias is not just", and "Callias is unjust"; which of these are contraries?
     From: Aristotle (On Interpretation [c.330 BCE], 23a31)
From one thing alone we can infer its contrary [Aristotle]
     Full Idea: One member of a pair of contraries is sufficient to discern both itself and its opposite.
     From: Aristotle (De Anima [c.329 BCE], 411a02)
     A reaction: This obviously requires prior knowledge of what the opposite is. He says you can infer the crooked from the straight. You can hardly use light in isolation to infer dark [see DA 418b17]. What's the opposite of a pig?
Two falsehoods can be contrary to one another [Aristotle]
     Full Idea: There are falsehoods which are contrary to one another and cannot be the case together e.g. that a man is a horse or a cow.
     From: Aristotle (Posterior Analytics [c.327 BCE], 88a29)
There is no middle ground in contradiction, but there is in contrariety [Aristotle]
     Full Idea: With contradiction there can be no intermediate state, whereas with contrariety there can be.
     From: Aristotle (Metaphysics [c.324 BCE], 1055b02)
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 / B. Laws of Thought / 5. Opposites
If everything is made of opposites, are the opposed things made of opposites? [Aristotle]
     Full Idea: If all things are composed of opposites, how can the things of which the opposites are made be composed of opposites?
     From: Aristotle (Metaphysics [c.324 BCE], 1075a23)
     A reaction: A nice warning against being too simplistic in metaphysics.
Not everything is composed of opposites; what, for example, is the opposite of matter? [Aristotle]
     Full Idea: All things are not composed of opposites, because matter is not the opposite of anything.
     From: Aristotle (Metaphysics [c.324 BCE], 1075a28)
     A reaction: A nice counterexample
2. Reason / C. Styles of Reason / 1. Dialectic
Dialectic starts from generally accepted opinions [Aristotle]
     Full Idea: Reasoning is dialectical which reasons from generally accepted opinions.
     From: Aristotle (Topics [c.331 BCE], 100a30)
     A reaction: This is right at the heart of Aristotle's philosophical method, and Greek thinking generally. There are nice modern debates about 'folk' understanding, derived from science (e.g. quantum theory) which suggest that starting from normal views is a bad idea.
It is the role of dialectic to survey syllogisms [Aristotle]
     Full Idea: It belongs to dialectic to survey equally all kinds of syllogism.
     From: Aristotle (The Art of Rhetoric [c.350 BCE], 1355a08)
     A reaction: Since dialectic is central to philosophy, this implies that philosophers ought to be students of logic. This duty seems to me to be taken more seriously in the analytical tradition than in the 'continental' tradition.
Dialectic aims to start from generally accepted opinions, and lead to a contradiction [Aristotle]
     Full Idea: Dialectical arguments are those which, starting from generally accepted opinions, reason to establish a contradiction.
     From: Aristotle (Sophistical Refutations [c.331 BCE], 165b03)
2. Reason / C. Styles of Reason / 3. Eristic
Competitive argument aims at refutation, fallacy, paradox, solecism or repetition [Aristotle]
     Full Idea: Those who compete and contend in argument aim at five objects: refutation, fallacy, paradox, solecism, and the reduction of one's opponent to a state of babbling, that is, making him say the same thing over and over again.
     From: Aristotle (Sophistical Refutations [c.331 BCE], 165b15)
2. Reason / D. Definition / 1. Definitions
There can't be one definition of two things, or two definitions of the same thing [Aristotle]
     Full Idea: There cannot possibly be one definition of two things, or two definitions of the same thing.
     From: Aristotle (Topics [c.331 BCE], 154a11)
     A reaction: The second half of this is much bolder and more controversial, and plenty of modern thinkers would flatly reject it. Are definitions contextual, that is, designed for some specific human purpose. Must definitions be of causes?
Definitions are easily destroyed, since they can contain very many assertions [Aristotle]
     Full Idea: A definition is the easiest of all things to destroy; for, since it contains many assertions, the opportunities which it offers are very numerous, and the more abundant the material, the more quickly the reasoning can set to work.
     From: Aristotle (Topics [c.331 BCE], 155a03)
     A reaction: I quote this to show that Aristotle expected many definitions to be very long affairs (maybe even of book length?)
The parts of a definition are isomorphic to the parts of the entity [Aristotle]
     Full Idea: The definition is an account, and every account has its parts, and there is an isomorphism between the relation of the account to the entity that it concerns and the relation of a part of the account to a part of the entity.
     From: Aristotle (Metaphysics [c.324 BCE], 1034b20)
     A reaction: This makes a definition sound like a catalogue of parts, which is likely to miss something important, such as the overall form, or the function. Aristotle has much more to say on the subject of definition. Cf. Russell's congruence view of truth.
The material element may be essential to a definition [Aristotle]
     Full Idea: One strays from the purpose of definitions if one confines oneself to a formal account and simply discards the material element.
     From: Aristotle (Metaphysics [c.324 BCE], 1036b20)
If we define 'man' as 'two-footed animal', why does that make man a unity? [Aristotle]
     Full Idea: What makes it the case that, if we call the account of something a 'definition', that thing is a unity? If 'two-footed animal' is the account of man, and a definition, why, then, is 'man' a single thing and not a plurality (viz. animal and two-footed)?
     From: Aristotle (Metaphysics [c.324 BCE], 1037b10)
     A reaction: The obvious answer, I would have thought, is that we can think of man as a unity or as a plurality, depending on which aspect we are interested in. I see no problem with this. Nature offers us unities, but we ultimately select them.
2. Reason / D. Definition / 3. Types of Definition
You can't define particulars, because accounts have to be generalised [Aristotle]
     Full Idea: It is impossible to define particulars. …The fact is that an account is general.
     From: Aristotle (Metaphysics [c.324 BCE], 1040a33-)
     A reaction: Aristotle rejects attempts to define the Sun as possible counterexamples. Since this claims rests on the idea of an account [logos], I presume the point is actually that definitions are linguistic, and must use general words.
2. Reason / D. Definition / 4. Real Definition
A definition must be of something primary [Aristotle]
     Full Idea: We can assign a term to any 'account' whatever, so that the Iliad would be a definition! No, a definition must be of something primary.
     From: Aristotle (Metaphysics [c.324 BCE], 1030a08)
     A reaction: At first hearing you may doubt this claim, but Aristotle's example clinches it beautifully. Are you really going to say that The Iliad is the definition of 'Iliad'?
Only substance [ousias] admits of definition [Aristotle]
     Full Idea: Only substance admits of definition.
     From: Aristotle (Metaphysics [c.324 BCE], 1030b34)
Sometimes parts must be mentioned in definitions of essence, and sometimes not [Aristotle]
     Full Idea: In some instances the account of the what-it-was-to-be-that-thing contains the parts of the thing defined and in others not.
     From: Aristotle (Metaphysics [c.324 BCE], 1037a22)
     A reaction: This is helpful in understanding what an essence is supposed to be. I take it to be sometimes a structure, with parts, and sometimes more like a guiding principle, more abstract in character.
Aristotelian definitions aim to give the essential properties of the thing defined [Aristotle, by Quine]
     Full Idea: A real definition, according to the Aristotelian tradition, gives the essence of the kind of thing defined. Man is defined as a rational animal, and thus rationality and animality are of the essence of each of us.
     From: report of Aristotle (works [c.330 BCE]) by Willard Quine - Vagaries of Definition p.51
     A reaction: Compare Idea 4385. Personally I prefer the Aristotelian approach, but we may have to say 'We cannot identify the essence of x, and so x cannot be defined'. Compare 'his mood was hard to define' with 'his mood was hostile'.
Definitions are of what something is, and that is universal [Aristotle]
     Full Idea: Definitions are thought to be of what something is, and what something is is in every case universal and positive.
     From: Aristotle (Posterior Analytics [c.327 BCE], 90b05)
     A reaction: This is exhibit A for those who think that Aristotelian essences concern the genus, rather than the particular. I suspect that this idea is best expressed as 'all we can say by way of definition of a particular thing involves the use of universals'.
An Aristotelian definition is causal [Aristotle, by Witt]
     Full Idea: An Aristotelian definition is causal.
     From: report of Aristotle (Posterior Analytics [c.327 BCE], Bk II.2) by Charlotte Witt - Substance and Essence in Aristotle 1.5
     A reaction: [She refers us to Posterior Analytics II.2] This is important if we are tempted to follow a modern line of saying that we want Aristotelian essences, and that these are definitions. We ain't thinking of dictionaries.
Definition by division needs predicates, which are well ordered and thorough [Aristotle]
     Full Idea: To establish a definition through division, you must aim for three things: you must take what is predicated in what the thing is; you must order these items as first or second; and you must ensure that these are all there are.
     From: Aristotle (Posterior Analytics [c.327 BCE], 97a23)
     A reaction: This gives an indication of the thoroughness that Aristotle expects from a definition. They aren't like dictionary definitions of words. He expects definitions to often be very lengthy (see Idea 12292).
You can define objects by progressively identifying what is the same and what is different [Aristotle]
     Full Idea: Find what is in common among items similar and undifferentiated, then do the same for items of the same kind as the first group but a different form, and so on, till you come to a single account: this will be the definition of the object.
     From: Aristotle (Posterior Analytics [c.327 BCE], 97b07-14)
     A reaction: [His example is distinguishing 'magnanimity' from 'indifference to fortune' among people] Presumably this process works for the formation of new concepts (e.g. in biology), as well as for the definition of familiars in terms of other familiars.
Definitions need the complex features of form, and don't need to mention the category [Aristotle, by Wedin]
     Full Idea: Met. Z.10-11 is committed to the complexity of form and suggests that the complexity is expressed in definitions that articulate, in the case of 'man', the salient faculties and functions, and none of these need mention 'man'.
     From: report of Aristotle (Metaphysics [c.324 BCE], 1034b20-1037b) by Michael V. Wedin - Aristotle's Theory of Substance X.5
     A reaction: This is a very strong statement of the view that identifying genus and species are not at all what Aristotle wants in his final account of essence. The features mentioned here would, though, clearly count as 'differentiae'.
2. Reason / D. Definition / 5. Genus and Differentia
The differentia indicate the qualities, but not the essence [Aristotle]
     Full Idea: No differentia indicates the essence [ti estin], but rather some quality, such as 'pedestrian' or 'biped'.
     From: Aristotle (Topics [c.331 BCE], 122b17)
     A reaction: We must disentangle this, since essence is what is definable, and definition seems to give us the essence, and yet it appears that definition only requires genus and differentia. Differentiae seem to be both generic and fine-grained. See Idea 12280!
In definitions the first term to be assigned ought to be the genus [Aristotle]
     Full Idea: In definitions the first term to be assigned ought to be the genus.
     From: Aristotle (Topics [c.331 BCE], 132a12)
     A reaction: We mustn't be deluded into thinking that nothing else is required. I take the increasing refinement of differentiae to be where the real action is. The genus gives you 70% of the explanation.
The genera and the differentiae are part of the essence [Aristotle]
     Full Idea: The genera and the differentiae are predicated in the category of essence.
     From: Aristotle (Topics [c.331 BCE], 153a19)
     A reaction: The definition is words, and the essence is real, so our best definition might not fully attain to the essence. Aristotle has us reaching out to the world through our definitions.
Aristotelian definition involves first stating the genus, then the differentia of the thing [Aristotle, by Urmson]
     Full Idea: For Aristotle, to give a definition one must first state the genus and then the differentia of the kind of thing to be defined.
     From: report of Aristotle (works [c.330 BCE]) by J.O. Urmson - Aristotle's Doctrine of the Mean p.157
     A reaction: Presumably a modern definition would just be a list of properties, but Aristotle seeks the substance. How does he define a genus? - by placing it in a further genus?
'Plane' is the genus of plane figures, and 'solid' of solids, with differentiae picking out types of corner [Aristotle]
     Full Idea: 'Plane' is the genus of figures in the plane, and 'solid' is the genus of solids. For every figure is either a plane with abc features or a solid with xyz features, so it is the plane and solid which underlie these differentiae.
     From: Aristotle (Metaphysics [c.324 BCE], 1024b01)
     A reaction: Thus you could hardly define a square by merely mentioning that it is a 'plane figure', and you would need pretty precise differentiae before you could be certain you were only dealing with a square, and not a parallelogram.
Whiteness can only belong to man because an individual like Callias happens to be white [Aristotle]
     Full Idea: If Callias is a white man, then whiteness belongs in a way to Callias, or to man, in as much as Callias, to whom it is accidental here to be a man, is white.
     From: Aristotle (Metaphysics [c.324 BCE], 1030b20)
     A reaction: The point here is that 'white' can only belong to 'man' because some individual man happens to be white.
A definition is of the universal and of the kind [Aristotle]
     Full Idea: A definition is of the universal [tou katholou] and the form [tou eidous, kind, species].
     From: Aristotle (Metaphysics [c.324 BCE], 1036a28)
     A reaction: [Alternative translations by Vasilis Politis] Since the essence of a thing is a particular (Idea 11382), this seems to mean that the definition is NOT giving the essence, contrary to the account of Kit Fine. I take the essence to be explanatory.
Definition by division is into genus and differentiae [Aristotle]
     Full Idea: The contents of definition by division are the so-called primary genus (such as 'animal') and the differentiae. ...It should always be prosecuted until the level of non-differentiation is reached, ...and the last differentia will be the substance.
     From: Aristotle (Metaphysics [c.324 BCE], 1037b30)
     A reaction: [Second half at 1038a14] Note that this is only one type of Aristotelian definition, the 'definition by division'. The aim of this type of definition is to analyse down to substance. Presumably you can't ignore crucial features found on the way?
If the genus is just its constitutive forms (or matter), then the definition is the account of the differentiae [Aristotle]
     Full Idea: If the genus simpliciter does not exist over and above the specific forms constitutive of it, alternatively if it exists just as matter, it is evident what the definition is, the account derived just from the differentiae.
     From: Aristotle (Metaphysics [c.324 BCE], 1038a05-)
     A reaction: This is how I understand an Aristotelian definition - as a lengthy and fine-grained account of the details which pick out some individual within the main genus which constitutes it.
If I define you, I have to use terms which are all true of other things too [Aristotle]
     Full Idea: Suppose I was trying to define you. I would say you are an animal that is lean or white or some such, all of which also apply to other things.
     From: Aristotle (Metaphysics [c.324 BCE], 1040a13)
     A reaction: Commentators have taken this to mean that Aristotle is only interested in kinds and not individuals, but recent thinking says this is wrong. Universals prevent you from really getting at the thing you want to define. Definitions are limited.
Species and genera are largely irrelevant in 'Metaphysics' [Aristotle, by Wedin]
     Full Idea: Species and genera are largely irrelevant to the program of 'Metaphysics'.
     From: report of Aristotle (Metaphysics [c.324 BCE], kind) by Michael V. Wedin - Aristotle's Theory of Substance III.10
     A reaction: The idea seems to be that Aristotle is seeking tools for getting at the primary being of a thing, and the notion of 'form' strikes him as a better account, because it explains the genera and species, rather than just naming them.
Aristotle's definitions are not unique, but apply to a range of individuals [Aristotle, by Witt]
     Full Idea: I take Aristotle to be arguing that no definition applies uniquely to an individual - it is always potentially applicable to a range of individuals.
     From: report of Aristotle (Metaphysics [c.324 BCE], defs) by Charlotte Witt - Substance and Essence in Aristotle 4.2 n7
     A reaction: So much the worse for Aristotle, I think. Surely unique entities can be defined? No one thinks their pet dog is just any dog, even after the age and breed have been identified.
We describe the essence of a particular thing by means of its differentiae [Aristotle]
     Full Idea: We usually isolate the appropriate description of the essence of a particular thing by means of the differentiae which are peculiar to it.
     From: Aristotle (Topics [c.331 BCE], 108b05)
     A reaction: I take this to be important for showing the definition is more than mere categorisation. A good definition homes in the particular, by gradually narrowing down the differentiae.
Differentia are generic, and belong with genus [Aristotle]
     Full Idea: The differentia, being generic in character, should be ranged with the genus.
     From: Aristotle (Topics [c.331 BCE], 101b18)
     A reaction: This does not mean that naming the differentia amounts to mere classification. I presume we can only state individual differences by using a language which is crammed full of universals.
'Genus' is part of the essence shared among several things [Aristotle]
     Full Idea: A 'genus' is that which is predicated in the category of essence of several things which differ in kind.
     From: Aristotle (Topics [c.331 BCE], 102a32)
     A reaction: Hence a genus is likely to be expressed by a universal, a one-over-many. A particular will be a highly individual collection of various genera, but what ensures the uniqueness of each thing, if they are indiscernible?
2. Reason / D. Definition / 6. Definition by Essence
The definition is peculiar to one thing, not common to many [Aristotle]
     Full Idea: The definition ought to be peculiar to one thing, not common to many.
     From: Aristotle (Topics [c.331 BCE], 149b24)
     A reaction: I take this to be very important, against those who think that definition is no more than mere categorisation. To explain, you must get down to the level of the individual. We must explain that uniquely docile tiger.
A definition is an account of a what-it-was-to-be-that-thing [Aristotle]
     Full Idea: A definition is an account of a what-it-was-to-be-that-thing.
     From: Aristotle (Metaphysics [c.324 BCE], 1031a12)
     A reaction: This is cited by Kit Fine, as expounding his view that essence is definition. He gives this text as "definition is the formula of the essence". Is the account the 'logos', I wonder? I like this view.
What it is and why it is are the same; screening defines and explains an eclipse [Aristotle]
     Full Idea: What it is and why it is are the same. What is an eclipse? Privation of light from the moon by screening of the earth. Why is there an eclipse? ...What is a harmony? A numerical ratio between high and low. Why do the high and low harmonize? The ratio.
     From: Aristotle (Posterior Analytics [c.327 BCE], 90a15)
     A reaction: This is right at the heart of Aristotelian essentialism, and (I take it) modern scientific essentialism. If you fully know what cigarette tars are, and what human cell structure is, you understand immediately why cigarettes cause cancer.
Essence is not all the necessary properties, since these extend beyond the definition [Aristotle, by Witt]
     Full Idea: Aristotle never thought of an essence as comprising all the necessary properties of an object. In Met VII.4 he limits per se predication appropriate to essences to the definition, and in Topics he distinguishes definition from the 'proprium'.
     From: report of Aristotle (Metaphysics [c.324 BCE]) by Charlotte Witt - Substance and Essence in Aristotle 4.1
     A reaction: [Topics 102a20-25] There seems to be consensus among scholars about this, and only a few misguided modern metaphysicians identify essences with the necessary properties (or maybe the non-trivial necessary properties).
2. Reason / E. Argument / 3. Analogy
Some things cannot be defined, and only an analogy can be given [Aristotle]
     Full Idea: It is not right to seek a definition for everything - for some things an overview is to be had by analogy.
     From: Aristotle (Metaphysics [c.324 BCE], 1048a33)
     A reaction: This is what David Lewis called the 'way of example' in defining what is meant by 'abstract objects'.
2. Reason / F. Fallacies / 2. Infinite Regress
Not everything can be proven, because that would lead to an infinite regress [Aristotle]
     Full Idea: It must be true, quite generally, that not everything can be proven, on pain of an infinite regress.
     From: Aristotle (Metaphysics [c.324 BCE], 1006a09)
     A reaction: Compare Idea 1672, where the possibility of a circular set of mutual proofs is considered. Aristotle seems committed to the present idea.
2. Reason / F. Fallacies / 3. Question Begging
Men are natural leaders (apart from the unnatural ones) [Aristotle]
     Full Idea: A male, unless he is somehow formed contrary to nature, is by nature more capable of leading than a female.
     From: Aristotle (Politics [c.332 BCE], 1259b01)
     A reaction: Beautiful! The greatest of all philosophers offers us a perfect perpetration of the No True Scotsman Fallacy! If the question is 'are men natural leaders?', this seems to beg it.
2. Reason / F. Fallacies / 5. Fallacy of Composition
'If each is small, so too are all' is in one way false, for the whole composed of all is not small [Aristotle]
     Full Idea: The sophistical argument 'if each is small, so too are all' is in one way true and in another false. For the whole composed of all the parts is not small, but it is composed of small parts.
     From: Aristotle (Politics [c.332 BCE], 1307b36)
     A reaction: If neurons can't think, then brains can't think.
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.