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All the ideas for 'works', 'What Required for Foundation for Maths?' and 'The Sentiment of Rationality'

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74 ideas

1. Philosophy / A. Wisdom / 1. Nature of Wisdom
There is practical wisdom (for action), and theoretical wisdom (for deep understanding) [Aristotle, by Whitcomb]
     Full Idea: Aristotle takes wisdom to come in two forms, the practical and the theoretical, the former of which is good judgement about how to act, and the latter of which is deep knowledge or understanding.
     From: report of Aristotle (works [c.330 BCE]) by Dennis Whitcomb - Wisdom Intro
     A reaction: The interesting question is then whether the two are connected. One might be thoroughly 'sensible' about action, without counting as 'wise', which seems to require a broader view of what is being done. Whitcomb endorses Aristotle on this idea.
It is wisdom to believe what you desire, because belief is needed to achieve it [James]
     Full Idea: Clearly it is often the part of wisdom to believe what one desires; for the belief is one of indispensable preliminary conditions of the realisation of its object.
     From: William James (The Sentiment of Rationality [1882], p.43)
     A reaction: Roughly, action is impossible without optimism about possible success. This may count as instinct, rather than 'wisdom'.
1. Philosophy / D. Nature of Philosophy / 1. Philosophy
All good philosophers start from a dumb conviction about which truths can be revealed [James]
     Full Idea: Every philosopher whose initiative counts for anything in the evolution of thought has taken his stand on a sort of dumb conviction that the truth must lie in one direction rather than another, and a preliminary assurance that this can be made to work.
     From: William James (The Sentiment of Rationality [1882], p.40)
     A reaction: I would refer to this as 'intuition', which I think of as reasons (probably good reasons) which cannot yet be articulated. Hence I like this idea very much, except for the word 'dumb'. It is more like a rational vision, yet to be filled in.
1. Philosophy / E. Nature of Metaphysics / 3. Metaphysical Systems
A complete system is just a classification of the whole world's ingredients [James]
     Full Idea: A completed theoretic philosophy can never be anything more than a completed classification of the world's ingredients.
     From: William James (The Sentiment of Rationality [1882], p.23)
     A reaction: I assume this is not just the physical ingredients, but must also include our conceptual scheme - but then we must first decide which is the best conceptual scheme to classify, and that's where the real action is. [He scorns such classifation later].
2. Reason / A. Nature of Reason / 2. Logos
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
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
2. Reason / A. Nature of Reason / 5. Objectivity
A single explanation must have a single point of view [James]
     Full Idea: A single explanation of a fact only explains it from a single point of view.
     From: William James (The Sentiment of Rationality [1882], p.23)
     A reaction: I take this to imply that multiple viewpoints lead us towards objectivity. The single viewpoint of an expert is of much greater value than that of a novice, on the whole.
2. Reason / B. Laws of Thought / 6. Ockham's Razor
Our greatest pleasure is the economy of reducing chaotic facts to one single fact [James]
     Full Idea: Our pleasure at finding that a chaos of facts is the expression of single underlying fact is like a musician's relief at discovering harmony. …The passion for economy of means in thought is the philosophic passion par excellence.
     From: William James (The Sentiment of Rationality [1882], p.21)
     A reaction: We do, though, possess an inner klaxon warning against stupid simplistic reductions. Reducing all the miseries of life to the workings of the Devil is not satisfactory, even it it is economical. Simplicities are dangerously tempting.
2. Reason / D. Definition / 2. Aims of Definition
Definitions make our intuitions mathematically useful [Mayberry]
     Full Idea: Definition provides us with the means for converting our intuitions into mathematically usable concepts.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.405-1)
2. Reason / D. Definition / 4. Real Definition
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'.
2. Reason / D. Definition / 5. Genus and Differentia
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?
2. Reason / E. Argument / 6. Conclusive Proof
Proof shows that it is true, but also why it must be true [Mayberry]
     Full Idea: When you have proved something you know not only that it is true, but why it must be true.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.405-2)
     A reaction: Note the word 'must'. Presumably both the grounding and the necessitation of the truth are revealed.
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
Set theory can't be axiomatic, because it is needed to express the very notion of axiomatisation [Mayberry]
     Full Idea: Set theory cannot be an axiomatic theory, because the very notion of an axiomatic theory makes no sense without it.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.413-2)
     A reaction: This will come as a surprise to Penelope Maddy, who battles with ways to accept the set theory axioms as the foundation of mathematics. Mayberry says that the basic set theory required is much more simple and intuitive.
There is a semi-categorical axiomatisation of set-theory [Mayberry]
     Full Idea: We can give a semi-categorical axiomatisation of set-theory (all that remains undetermined is the size of the set of urelements and the length of the sequence of ordinals). The system is second-order in formalisation.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.413-2)
     A reaction: I gather this means the models may not be isomorphic to one another (because they differ in size), but can be shown to isomorphic to some third ingredient. I think. Mayberry says this shows there is no such thing as non-Cantorian set theory.
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / f. Axiom of Infinity V
The misnamed Axiom of Infinity says the natural numbers are finite in size [Mayberry]
     Full Idea: The (misnamed!) Axiom of Infinity expresses Cantor's fundamental assumption that the species of natural numbers is finite in size.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.414-2)
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / e. Iterative sets
The set hierarchy doesn't rely on the dubious notion of 'generating' them [Mayberry]
     Full Idea: The idea of 'generating' sets is only a metaphor - the existence of the hierarchy is established without appealing to such dubious notions.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.414-2)
     A reaction: Presumably there can be a 'dependence' or 'determination' relation which does not involve actual generation.
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / f. Limitation of Size
Limitation of size is part of the very conception of a set [Mayberry]
     Full Idea: Our very notion of a set is that of an extensional plurality limited in size.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.415-2)
4. Formal Logic / G. Formal Mereology / 1. Mereology
Aristotle relativises the notion of wholeness to different measures [Aristotle, by Koslicki]
     Full Idea: Aristotle proposes to relativise unity and plurality, so that a single object can be both one (indivisible) and many (divisible) simultaneously, without contradiction, relative to different measures. Wholeness has degrees, with the strength of the unity.
     From: report of Aristotle (works [c.330 BCE]) by Kathrin Koslicki - The Structure of Objects 7.2.12
     A reaction: [see Koslicki's account of Aristotle for details] As always, the Aristotelian approach looks by far the most promising. Simplistic mechanical accounts of how parts make wholes aren't going to work. We must include the conventional and conceptual bit.
5. Theory of Logic / A. Overview of Logic / 2. History of Logic
The mainstream of modern logic sees it as a branch of mathematics [Mayberry]
     Full Idea: In the mainstream tradition of modern logic, beginning with Boole, Peirce and Schröder, descending through Löwenheim and Skolem to reach maturity with Tarski and his school ...saw logic as a branch of mathematics.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.410-1)
     A reaction: [The lesser tradition, of Frege and Russell, says mathematics is a branch of logic]. Mayberry says the Fregean tradition 'has almost died out'.
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
First-order logic only has its main theorems because it is so weak [Mayberry]
     Full Idea: First-order logic is very weak, but therein lies its strength. Its principle tools (Compactness, Completeness, Löwenheim-Skolem Theorems) can be established only because it is too weak to axiomatize either arithmetic or analysis.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.411-2)
     A reaction: He adds the proviso that this is 'unless we are dealing with structures on whose size we have placed an explicit, finite bound' (p.412-1).
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Only second-order logic can capture mathematical structure up to isomorphism [Mayberry]
     Full Idea: Second-order logic is a powerful tool of definition: by means of it alone we can capture mathematical structure up to isomorphism using simple axiom systems.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.412-1)
5. Theory of Logic / E. Structures of Logic / 1. Logical Form
For Aristotle, the subject-predicate structure of Greek reflected a substance-accident structure of reality [Aristotle, by O'Grady]
     Full Idea: Aristotle apparently believed that the subject-predicate structure of Greek reflected the substance-accident nature of reality.
     From: report of Aristotle (works [c.330 BCE]) by Paul O'Grady - Relativism Ch.4
     A reaction: We need not assume that Aristotle is wrong. It is a chicken-and-egg. There is something obvious about subject-predicate language, if one assumes that unified objects are part of nature, and not just conventional.
5. Theory of Logic / G. Quantification / 2. Domain of Quantification
Big logic has one fixed domain, but standard logic has a domain for each interpretation [Mayberry]
     Full Idea: The 'logica magna' [of the Fregean tradition] has quantifiers ranging over a fixed domain, namely everything there is. In the Boolean tradition the domains differ from interpretation to interpretation.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.410-2)
     A reaction: Modal logic displays both approaches, with different systems for global and local domains.
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
No Löwenheim-Skolem logic can axiomatise real analysis [Mayberry]
     Full Idea: No logic which can axiomatize real analysis can have the Löwenheim-Skolem property.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.412-1)
5. Theory of Logic / K. Features of Logics / 1. Axiomatisation
'Classificatory' axioms aim at revealing similarity in morphology of structures [Mayberry]
     Full Idea: The purpose of a 'classificatory' axiomatic theory is to single out an otherwise disparate species of structures by fixing certain features of morphology. ...The aim is to single out common features.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.406-2)
Axiomatiation relies on isomorphic structures being essentially the same [Mayberry]
     Full Idea: The central dogma of the axiomatic method is this: isomorphic structures are mathematically indistinguishable in their essential properties.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.406-2)
     A reaction: Hence it is not that we have to settle for the success of a system 'up to isomorphism', since that was the original aim. The structures must differ in their non-essential properties, or they would be the same system.
'Eliminatory' axioms get rid of traditional ideal and abstract objects [Mayberry]
     Full Idea: The purpose of what I am calling 'eliminatory' axiomatic theories is precisely to eliminate from mathematics those peculiar ideal and abstract objects that, on the traditional view, constitute its subject matter.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.407-1)
     A reaction: A very interesting idea. I have a natural antipathy to 'abstract objects', because they really mess up what could otherwise be a very tidy ontology. What he describes might be better called 'ignoring' axioms. The objects may 'exist', but who cares?
5. Theory of Logic / K. Features of Logics / 6. Compactness
No logic which can axiomatise arithmetic can be compact or complete [Mayberry]
     Full Idea: No logic which can axiomatise arithmetic can be compact or complete.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.412-1)
     A reaction: I take this to be because there are new truths in the transfinite level (as well as the problem of incompleteness).
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
Real numbers can be eliminated, by axiom systems for complete ordered fields [Mayberry]
     Full Idea: We eliminate the real numbers by giving an axiomatic definition of the species of complete ordered fields. These axioms are categorical (mutually isomorphic), and thus are mathematically indistinguishable.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.408-2)
     A reaction: Hence my clever mathematical friend says that it is a terrible misunderstanding to think that mathematics is about numbers. Mayberry says the reals are one ordered field, but mathematics now studies all ordered fields together.
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / b. Quantity
Greek quantities were concrete, and ratio and proportion were their science [Mayberry]
     Full Idea: Quantities for Greeks were concrete things - lines, surfaces, solids, times, weights. At the centre of their science of quantity was the beautiful theory of ratio and proportion (...in which the notion of number does not appear!).
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.407-2)
     A reaction: [He credits Eudoxus, and cites Book V of Euclid]
Real numbers were invented, as objects, to simplify and generalise 'quantity' [Mayberry]
     Full Idea: The abstract objects of modern mathematics, the real numbers, were invented by the mathematicians of the seventeenth century in order to simplify and to generalize the Greek science of quantity.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.407-2)
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
Cantor's infinite is an absolute, of all the sets or all the ordinal numbers [Mayberry]
     Full Idea: In Cantor's new vision, the infinite, the genuine infinite, does not disappear, but presents itself in the guise of the absolute, as manifested in the species of all sets or the species of all ordinal numbers.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.414-2)
Cantor extended the finite (rather than 'taming the infinite') [Mayberry]
     Full Idea: We may describe Cantor's achievement by saying, not that he tamed the infinite, but that he extended the finite.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.414-2)
6. Mathematics / B. Foundations for Mathematics / 1. Foundations for Mathematics
If proof and definition are central, then mathematics needs and possesses foundations [Mayberry]
     Full Idea: If we grant, as surely we must, the central importance of proof and definition, then we must also grant that mathematics not only needs, but in fact has, foundations.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.405-1)
The ultimate principles and concepts of mathematics are presumed, or grasped directly [Mayberry]
     Full Idea: The ultimate principles upon which mathematics rests are those to which mathematicians appeal without proof; and the primitive concepts of mathematics ...themselves are grasped directly, if grasped at all, without the mediation of definition.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.405-1)
     A reaction: This begs the question of whether the 'grasping' is purely a priori, or whether it derives from experience. I defend the latter, and Jenkins puts the case well.
Foundations need concepts, definition rules, premises, and proof rules [Mayberry]
     Full Idea: An account of the foundations of mathematics must specify four things: the primitive concepts for use in definitions, the rules governing definitions, the ultimate premises of proofs, and rules allowing advance from premises to conclusions.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.405-2)
Axiom theories can't give foundations for mathematics - that's using axioms to explain axioms [Mayberry]
     Full Idea: No axiomatic theory, formal or informal, of first or of higher order can logically play a foundational role in mathematics. ...It is obvious that you cannot use the axiomatic method to explain what the axiomatic method is.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.415-2)
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / d. Peano arithmetic
1st-order PA is only interesting because of results which use 2nd-order PA [Mayberry]
     Full Idea: The sole theoretical interest of first-order Peano arithmetic derives from the fact that it is a first-order reduct of a categorical second-order theory. Its axioms can be proved incomplete only because the second-order theory is categorical.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.412-1)
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / g. Incompleteness of Arithmetic
It is only 2nd-order isomorphism which suggested first-order PA completeness [Mayberry]
     Full Idea: If we did not know that the second-order axioms characterise the natural numbers up to isomorphism, we should have no reason to suppose, a priori, that first-order Peano Arithmetic should be complete.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.412-1)
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Set theory is not just first-order ZF, because that is inadequate for mathematics [Mayberry]
     Full Idea: The idea that set theory must simply be identified with first-order Zermelo-Fraenkel is surprisingly widespread. ...The first-order axiomatic theory of sets is clearly inadequate as a foundation of mathematics.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.412-2)
     A reaction: [He is agreeing with a quotation from Skolem].
We don't translate mathematics into set theory, because it comes embodied in that way [Mayberry]
     Full Idea: One does not have to translate 'ordinary' mathematics into the Zermelo-Fraenkel system: ordinary mathematics comes embodied in that system.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.415-1)
     A reaction: Mayberry seems to be a particular fan of set theory as spelling out the underlying facts of mathematics, though it has to be second-order.
Set theory is not just another axiomatised part of mathematics [Mayberry]
     Full Idea: The fons et origo of all confusion is the view that set theory is just another axiomatic theory and the universe of sets just another mathematical structure. ...The universe of sets ...is the world that all mathematical structures inhabit.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.416-1)
7. Existence / E. Categories / 2. Categorisation
Classification can only ever be for a particular purpose [James]
     Full Idea: Every way of classifying a thing is but a way of handling it for some particular purpose. Conceptions, 'kinds', are teleological instruments.
     From: William James (The Sentiment of Rationality [1882], p.24)
     A reaction: Could there not be ways of classifying which suit all of our purposes? If there were a naturally correct way to classifying things, then any pragmatist would probably welcome that. (I don't say there is such a way).
9. Objects / A. Existence of Objects / 2. Abstract Objects / a. Nature of abstracta
Real numbers as abstracted objects are now treated as complete ordered fields [Mayberry]
     Full Idea: The abstractness of the old fashioned real numbers has been replaced by generality in the modern theory of complete ordered fields.
     From: John Mayberry (What Required for Foundation for Maths? [1994], p.408-2)
     A reaction: In philosophy, I'm increasingly thinking that we should talk much more of 'generality', and a great deal less about 'universals'. (By which I don't mean that redness is just the set of red things).
9. Objects / C. Structure of Objects / 2. Hylomorphism / a. Hylomorphism
The unmoved mover and the soul show Aristotelian form as the ultimate mereological atom [Aristotle, by Koslicki]
     Full Idea: Aristotle's discussion of the unmoved mover and of the soul confirms the suspicion that form, when it is not thought of as the object represented in a definition, plays the role of the ultimate mereological atom within his system.
     From: report of Aristotle (works [c.330 BCE]) by Kathrin Koslicki - The Structure of Objects 6.6
     A reaction: Aristotle is concerned with which things are 'divisible', and he cites these two examples as indivisible, but they may be too unusual to offer an actual theory of how Aristotle builds up wholes from atoms. He denies atoms in matter.
9. Objects / C. Structure of Objects / 2. Hylomorphism / d. Form as unifier
The 'form' is the recipe for building wholes of a particular kind [Aristotle, by Koslicki]
     Full Idea: Thus in Aristotle we may think of an object's formal components as a sort of recipe for how to build wholes of that particular kind.
     From: report of Aristotle (works [c.330 BCE]) by Kathrin Koslicki - The Structure of Objects 7.2.5
     A reaction: In the elusive business of pinning down what Aristotle means by the crucial idea of 'form', this analogy strikes me as being quite illuminating. It would fit DNA in living things, and the design of an artifact.
11. Knowledge Aims / A. Knowledge / 1. Knowledge
For Aristotle, knowledge is of causes, and is theoretical, practical or productive [Aristotle, by Code]
     Full Idea: Aristotle thinks that in general we have knowledge or understanding when we grasp causes, and he distinguishes three fundamental types of knowledge - theoretical, practical and productive.
     From: report of Aristotle (works [c.330 BCE]) by Alan D. Code - Aristotle
     A reaction: Productive knowledge we tend to label as 'knowing how'. The centrality of causes for knowledge would get Aristotle nowadays labelled as a 'naturalist'. It is hard to disagree with his three types, though they may overlap.
12. Knowledge Sources / A. A Priori Knowledge / 1. Nature of the A Priori
The notion of a priori truth is absent in Aristotle [Aristotle, by Politis]
     Full Idea: The notion of a priori truth is conspicuously absent in Aristotle.
     From: report of Aristotle (works [c.330 BCE]) by Vassilis Politis - Aristotle and the Metaphysics 1.5
     A reaction: Cf. Idea 11240.
12. Knowledge Sources / C. Rationalism / 1. Rationalism
Aristotle is a rationalist, but reason is slowly acquired through perception and experience [Aristotle, by Frede,M]
     Full Idea: Aristotle is a rationalist …but reason for him is a disposition which we only acquire over time. Its acquisition is made possible primarily by perception and experience.
     From: report of Aristotle (works [c.330 BCE]) by Michael Frede - Aristotle's Rationalism p.173
     A reaction: I would describe this process as the gradual acquisition of the skill of objectivity, which needs the right knowledge and concepts to evaluate new experiences.
12. Knowledge Sources / E. Direct Knowledge / 2. Intuition
Aristotle wants to fit common intuitions, and therefore uses language as a guide [Aristotle, by Gill,ML]
     Full Idea: Since Aristotle generally prefers a metaphysical theory that accords with common intuitions, he frequently relies on facts about language to guide his metaphysical claims.
     From: report of Aristotle (works [c.330 BCE]) by Mary Louise Gill - Aristotle on Substance Ch.5
     A reaction: I approve of his procedure. I take intuition to be largely rational justifications too complex for us to enunciate fully, and language embodies folk intuitions in its concepts (especially if the concepts occur in many languages).
14. Science / A. Basis of Science / 1. Observation
Scientific genius extracts more than other people from the same evidence [James]
     Full Idea: What is the use of being a genius, unless with the same scientific evidence as other men, one can reach more truth than they?
     From: William James (The Sentiment of Rationality [1882], p.40)
     A reaction: This is aimed at Clifford's famous principle. He isn't actually contraverting the principle, but it is a nice point about evidence. Simple empiricists think detectives only have to stare at the evidence and the solution creates itself.
14. Science / A. Basis of Science / 6. Falsification
Experimenters assume the theory is true, and stick to it as long as result don't disappoint [James]
     Full Idea: Each tester of the truth of a theory …acts as if it were true, and expects the result to disappoint him if his assumption is false. The longer disappointment is delayed, the stronger grows his faith in his theory.
     From: William James (The Sentiment of Rationality [1882], p.42)
     A reaction: This is almost exactly Popper's falsificationist proposal for science, which interestingly shows the close relationship of his view to pragmatism. Believe it as long as it is still working.
14. Science / B. Scientific Theories / 1. Scientific Theory
Plato says sciences are unified around Forms; Aristotle says they're unified around substance [Aristotle, by Moravcsik]
     Full Idea: Plato's unity of science principle states that all - legitimate - sciences are ultimately about the Forms. Aristotle's principle states that all sciences must be, ultimately, about substances, or aspects of substances.
     From: report of Aristotle (works [c.330 BCE], 1) by Julius Moravcsik - Aristotle on Adequate Explanations 1
14. Science / C. Induction / 3. Limits of Induction
We can't know if the laws of nature are stable, but we must postulate it or assume it [James]
     Full Idea: That nature will follow tomorrow the same laws that she follows today is a truth which no man can know; but in the interests of cognition as well as of action we must postulate or assume it.
     From: William James (The Sentiment of Rationality [1882], p.39)
     A reaction: The stability of nature is something to be assessed, not something taken for granted. If you arrive in a new city and it all seems quiet, you keep your fingers crossed and treat it as stable. But revolution or coup could be just round the corner.
14. Science / C. Induction / 6. Bayes's Theorem
Trying to assess probabilities by mere calculation is absurd and impossible [James]
     Full Idea: The absurd abstraction of an intellect verbally formulating all its evidence and carefully estimating the probability thereof solely by the size of a vulgar fraction, is as ideally inept as it is practically impossible.
     From: William James (The Sentiment of Rationality [1882], p.40)
     A reaction: James probably didn't know about Bayes, but this is directed at the Bayesian approach. My view is that full rational assessment of coherence is a much better bet than a Bayesian calculation. Factors must be weighted.
14. Science / D. Explanation / 1. Explanation / a. Explanation
Aristotelian explanations are facts, while modern explanations depend on human conceptions [Aristotle, by Politis]
     Full Idea: For Aristotle things which explain (the explanantia) are facts, which should not be associated with the modern view that says explanations are dependent on how we conceive and describe the world (where causes are independent of us).
     From: report of Aristotle (works [c.330 BCE]) by Vassilis Politis - Aristotle and the Metaphysics 2.1
     A reaction: There must be some room in modern thought for the Aristotelian view, if some sort of robust scientific realism is being maintained against the highly linguistic view of philosophy found in the twentieth century.
14. Science / D. Explanation / 2. Types of Explanation / a. Types of explanation
Aristotle's standard analysis of species and genus involves specifying things in terms of something more general [Aristotle, by Benardete,JA]
     Full Idea: The standard Aristotelian doctrine of species and genus in the theory of anything whatever involves specifying what the thing is in terms of something more general.
     From: report of Aristotle (works [c.330 BCE]) by José A. Benardete - Metaphysics: the logical approach Ch.10
14. Science / D. Explanation / 2. Types of Explanation / j. Explanations by reduction
We have a passion for knowing the parts of something, rather than the whole [James]
     Full Idea: Alongside the passion for simplification …is the passion for distinguishing; it is the passion to be acquainted with the parts rather than to comprehend the whole.
     From: William James (The Sentiment of Rationality [1882], p.22)
     A reaction: As I child I dismantled almost every toy I was given. This seems to be the motivation for a lot of analytic philosophy, but Aristotle also tended to think that way.
14. Science / D. Explanation / 2. Types of Explanation / k. Explanations by essence
Aristotle regularly says that essential properties explain other significant properties [Aristotle, by Kung]
     Full Idea: The view that essential properties are those in virtue of which other significant properties of the subjects under investigation can be explained is encountered repeatedly in Aristotle's work.
     From: report of Aristotle (works [c.330 BCE]) by Joan Kung - Aristotle on Essence and Explanation IV
     A reaction: What does 'significant' mean here? I take it that the significant properties are the ones which explain the role, function and powers of the object.
15. Nature of Minds / A. Nature of Mind / 1. Mind / b. Purpose of mind
The mind has evolved entirely for practical interests, seen in our reflex actions [James]
     Full Idea: It is far too little recognised how entirely the intellect is built up of practical interests. The theory of evolution is beginning to do very good service by its reduction of all mentality to the type of reflex action.
     From: William James (The Sentiment of Rationality [1882], p.34)
     A reaction: Hands evolved for manipulating tools end up playing the piano. Minds evolved for action can be afflicted with boredom. He's not wrong, but he is risking the etymological fallacy (origin = purpose). I take navigation to be the original purpose of mind.
15. Nature of Minds / A. Nature of Mind / 7. Animal Minds
Dogs' curiosity only concerns what will happen next [James]
     Full Idea: A dog's curiosity about the movements of his master or a strange object only extends as far as the point of what is going to happen next.
     From: William James (The Sentiment of Rationality [1882], p.31)
     A reaction: Good. A nice corrective to people like myself who are tempted to inflate animal rationality, in order to emphasise human evolutionary continuity with them. It is hard to disagree with his observation. But dogs do make judgements! True/false!
18. Thought / A. Modes of Thought / 5. Rationality / a. Rationality
How can the ground of rationality be itself rational? [James]
     Full Idea: Can that which is the ground of rationality in all else be itself properly called rational?
     From: William James (The Sentiment of Rationality [1882], p.25)
     A reaction: This is the perennial problem in deciding grounds, and in deciding what to treat as primitive. The stoics see the whole of nature as rational. Cf how can the ground of what is physical be itself physical?
18. Thought / A. Modes of Thought / 5. Rationality / b. Human rationality
It seems that we feel rational when we detect no irrationality [James]
     Full Idea: I think there are very good grounds for upholding the view that the feeling of rationality is constituted merely by the absence of any feelings of irrationality.
     From: William James (The Sentiment of Rationality [1882], p.20)
     A reaction: A very interesting proposal. Nothing is more basic to logic (well, plausible versions of logic) than the principle of non-contradiction - perhaps because it is the foundation of our natural intellectual equipment.
18. Thought / A. Modes of Thought / 5. Rationality / c. Animal rationality
Aristotle and the Stoics denied rationality to animals, while Platonists affirmed it [Aristotle, by Sorabji]
     Full Idea: Aristotle, and also the Stoics, denied rationality to animals. …The Platonists, the Pythagoreans, and some more independent Aristotelians, did grant reason and intellect to animals.
     From: report of Aristotle (works [c.330 BCE]) by Richard Sorabji - Rationality 'Denial'
     A reaction: This is not the same as affirming or denying their consciousness. The debate depends on how rationality is conceived.
19. Language / E. Analyticity / 2. Analytic Truths
The notion of analytic truth is absent in Aristotle [Aristotle, by Politis]
     Full Idea: The notion of analytic truth is conspicuously absent in Aristotle.
     From: report of Aristotle (works [c.330 BCE]) by Vassilis Politis - Aristotle and the Metaphysics 1.5
     A reaction: Cf. Idea 11239.
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / d. Biological ethics
Evolution suggests prevailing or survival as a new criterion of right and wrong [James]
     Full Idea: The philosophy of evolution offers us today a new criterion, which is objective and fixed, as an ethical test between right and wrong: That is to be called good which is destined to prevail or survive.
     From: William James (The Sentiment of Rationality [1882], p.44)
     A reaction: Perceptive for its time. Herbert Spencer may have suggested the idea. James dismisses it, because it implies a sort of fatalism, whereas genuine moral choices are involved in what survives.
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / e. Human nature
Aristotle never actually says that man is a rational animal [Aristotle, by Fogelin]
     Full Idea: To the best of my knowledge (and somewhat to my surprise), Aristotle never actually says that man is a rational animal; however, he all but says it.
     From: report of Aristotle (works [c.330 BCE]) by Robert Fogelin - Walking the Tightrope of Reason Ch.1
     A reaction: When I read this I thought that this database would prove Fogelin wrong, but it actually supports him, as I can't find it in Aristotle either. Descartes refers to it in Med.Two. In Idea 5133 Aristotle does say that man is a 'social being'. But 22586!
25. Social Practice / E. Policies / 5. Education / a. Aims of education
It is the mark of an educated mind to be able to entertain an idea without accepting it [Aristotle]
     Full Idea: It is the mark of an educated mind to be able to entertain an idea without accepting it.
     From: Aristotle (works [c.330 BCE])
     A reaction: The epigraph on a David Chalmers website. A wonderful remark, and it should be on the wall of every beginners' philosophy class. However, while it is in the spirit of Aristotle, it appears to be a misattribution with no ancient provenance.
25. Social Practice / E. Policies / 5. Education / b. Education principles
Aristotle said the educated were superior to the uneducated as the living are to the dead [Aristotle, by Diog. Laertius]
     Full Idea: Aristotle was asked how much educated men were superior to those uneducated; "As much," he said, "as the living are to the dead."
     From: report of Aristotle (works [c.330 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 05.1.11
26. Natural Theory / A. Speculations on Nature / 5. Infinite in Nature
There are potential infinities (never running out), but actual infinity is incoherent [Aristotle, by Friend]
     Full Idea: Aristotle developed his own distinction between potential infinity (never running out) and actual infinity (there being a collection of an actual infinite number of things, such as places, times, objects). He decided that actual infinity was incoherent.
     From: report of Aristotle (works [c.330 BCE]) by Michèle Friend - Introducing the Philosophy of Mathematics 1.3
     A reaction: Friend argues, plausibly, that this won't do, since potential infinity doesn't make much sense if there is not an actual infinity of things to supply the demand. It seems to just illustrate how boggling and uncongenial infinity was to Aristotle.
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / a. Greek matter
Aristotle's matter can become any other kind of matter [Aristotle, by Wiggins]
     Full Idea: Aristotle's conception of matter permits any kind of matter to become any other kind of matter.
     From: report of Aristotle (works [c.330 BCE]) by David Wiggins - Substance 4.11.2
     A reaction: This is obviously crucial background information when we read Aristotle on matter. Our 92+ elements, and fixed fundamental particles, gives a quite different picture. Aristotle would discuss form and matter quite differently now.
26. Natural Theory / C. Causation / 8. Particular Causation / d. Selecting the cause
Understanding by means of causes is useless if they are not reduced to a minimum number [James]
     Full Idea: The knowledge of things by their causes, which is often given as a definition of rational knowledge, is useless unless the causes converge to a minimum number, while still producing the maximum number of effects.
     From: William James (The Sentiment of Rationality [1882], p.21)
     A reaction: This is certainly the psychological motivation for trying to identify 'the' cause of something, but James always tries to sell such things as subjective. 'Useless' to one person is a subjective criterion; useless to anyone is much more objective.
29. Religion / A. Polytheistic Religion / 2. Greek Polytheism
The concepts of gods arose from observing the soul, and the cosmos [Aristotle, by Sext.Empiricus]
     Full Idea: Aristotle said that the conception of gods arose among mankind from two originating causes, namely from events which concern the soul and from celestial phenomena.
     From: report of Aristotle (works [c.330 BCE], Frag 10) by Sextus Empiricus - Against the Physicists (two books) I.20
     A reaction: The cosmos suggests order, and possible creation. What do events of the soul suggest? It doesn't seem to be its non-physical nature, because Aristotle is more of a functionalist. Puzzling. (It says later that gods are like the soul).
29. Religion / B. Monotheistic Religion / 4. Christianity / a. Christianity
Early Christianity says God recognises the neglected weak and tender impulses [James]
     Full Idea: In what did the emancipating message of primitive Christianity consist but in the announcement that God recognizes those weak and tender impulses which paganism had so rudely overlooked.
     From: William James (The Sentiment of Rationality [1882], p.36)
     A reaction: Nietzsche says these are the virtues of a good slave. Previous virtues were dominated by military needs, but the new virtues are those of large cities, where communal living with strangers is the challenge.