Combining Texts

All the ideas for 'Confessions', 'What Numbers Could Not Be' and 'Philosophy of Mathematics'

expand these ideas     |    start again     |     specify just one area for these texts


79 ideas

2. Reason / D. Definition / 2. Aims of Definition
Definitions should be replaceable by primitives, and should not be creative [Brown,JR]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / d. Infinite Sets
Set theory says that natural numbers are an actual infinity (to accommodate their powerset) [Brown,JR]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / d. Naïve logical sets
Naïve set theory assumed that there is a set for every condition [Brown,JR]
Nowadays conditions are only defined on existing sets [Brown,JR]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / e. Iterative sets
The 'iterative' view says sets start with the empty set and build up [Brown,JR]
4. Formal Logic / F. Set Theory ST / 7. Natural Sets
A flock of birds is not a set, because a set cannot go anywhere [Brown,JR]
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
If a proposition is false, then its negation is true [Brown,JR]
5. Theory of Logic / K. Features of Logics / 1. Axiomatisation
Axioms are either self-evident, or stipulations, or fallible attempts [Brown,JR]
5. Theory of Logic / L. Paradox / 4. Paradoxes in Logic / c. Berry's paradox
Berry's Paradox finds a contradiction in the naming of huge numbers [Brown,JR]
6. Mathematics / A. Nature of Mathematics / 1. Mathematics
Mathematics is the only place where we are sure we are right [Brown,JR]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / a. Numbers
There are no such things as numbers [Benacerraf]
Numbers can't be sets if there is no agreement on which sets they are [Benacerraf]
'There are two apples' can be expressed logically, with no mention of numbers [Brown,JR]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / c. Priority of numbers
Benacerraf says numbers are defined by their natural ordering [Benacerraf, by Fine,K]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / f. Cardinal numbers
To understand finite cardinals, it is necessary and sufficient to understand progressions [Benacerraf, by Wright,C]
A set has k members if it one-one corresponds with the numbers less than or equal to k [Benacerraf]
To explain numbers you must also explain cardinality, the counting of things [Benacerraf]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / n. Pi
π is a 'transcendental' number, because it is not the solution of an equation [Brown,JR]
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / c. Counting procedure
We can count intransitively (reciting numbers) without understanding transitive counting of items [Benacerraf]
Someone can recite numbers but not know how to count things; but not vice versa [Benacerraf]
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / g. Applying mathematics
The application of a system of numbers is counting and measurement [Benacerraf]
Mathematics represents the world through structurally similar models. [Brown,JR]
6. Mathematics / B. Foundations for Mathematics / 2. Proof in Mathematics
There is no limit to how many ways something can be proved in mathematics [Brown,JR]
Computers played an essential role in proving the four-colour theorem of maps [Brown,JR]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / a. Axioms for numbers
For Zermelo 3 belongs to 17, but for Von Neumann it does not [Benacerraf]
The successor of x is either x and all its members, or just the unit set of x [Benacerraf]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / b. Mathematics is not set theory
Disputes about mathematical objects seem irrelevant, and mathematicians cannot resolve them [Benacerraf, by Friend]
No particular pair of sets can tell us what 'two' is, just by one-to-one correlation [Benacerraf, by Lowe]
If ordinal numbers are 'reducible to' some set-theory, then which is which? [Benacerraf]
Set theory may represent all of mathematics, without actually being mathematics [Brown,JR]
When graphs are defined set-theoretically, that won't cover unlabelled graphs [Brown,JR]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / a. Structuralism
If any recursive sequence will explain ordinals, then it seems to be the structure which matters [Benacerraf]
The job is done by the whole system of numbers, so numbers are not objects [Benacerraf]
The number 3 defines the role of being third in a progression [Benacerraf]
Number words no more have referents than do the parts of a ruler [Benacerraf]
Mathematical objects only have properties relating them to other 'elements' of the same structure [Benacerraf]
How can numbers be objects if order is their only property? [Benacerraf, by Putnam]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / d. Platonist structuralism
To see a structure in something, we must already have the idea of the structure [Brown,JR]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / e. Structuralism critique
Sets seem basic to mathematics, but they don't suit structuralism [Brown,JR]
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / a. For mathematical platonism
The irrationality of root-2 was achieved by intellect, not experience [Brown,JR]
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / b. Against mathematical platonism
Number-as-objects works wholesale, but fails utterly object by object [Benacerraf]
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / c. Against mathematical empiricism
There is an infinity of mathematical objects, so they can't be physical [Brown,JR]
Numbers are not abstracted from particulars, because each number is a particular [Brown,JR]
6. Mathematics / C. Sources of Mathematics / 5. Numbers as Adjectival
Empiricists base numbers on objects, Platonists base them on properties [Brown,JR]
Number words are not predicates, as they function very differently from adjectives [Benacerraf]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
The set-theory paradoxes mean that 17 can't be the class of all classes with 17 members [Benacerraf]
6. Mathematics / C. Sources of Mathematics / 7. Formalism
Does some mathematics depend entirely on notation? [Brown,JR]
For nomalists there are no numbers, only numerals [Brown,JR]
The most brilliant formalist was Hilbert [Brown,JR]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / a. Constructivism
There are no constructions for many highly desirable results in mathematics [Brown,JR]
Constructivists say p has no value, if the value depends on Goldbach's Conjecture [Brown,JR]
7. Existence / A. Nature of Existence / 2. Types of Existence
I prefer a lack of form to mean non-existence, than to think of some quasi-existence [Augustine]
7. Existence / C. Structure of Existence / 7. Abstract/Concrete / a. Abstract/concrete
David's 'Napoleon' is about something concrete and something abstract [Brown,JR]
7. Existence / D. Theories of Reality / 1. Ontologies
Three main questions seem to be whether a thing is, what it is, and what sort it is [Augustine]
9. Objects / F. Identity among Objects / 6. Identity between Objects
Identity statements make sense only if there are possible individuating conditions [Benacerraf]
12. Knowledge Sources / E. Direct Knowledge / 4. Memory
Mind and memory are the same, as shown in 'bear it in mind' or 'it slipped from mind' [Augustine]
Memory contains innumerable principles of maths, as well as past sense experiences [Augustine]
We would avoid remembering sorrow or fear if that triggered the emotions afresh [Augustine]
I can distinguish different smells even when I am not experiencing them [Augustine]
Why does joy in my mind make me happy, but joy in my memory doesn't? [Augustine]
15. Nature of Minds / A. Nature of Mind / 6. Anti-Individualism
Memory is so vast that I cannot recognise it as part of my mind [Augustine]
16. Persons / D. Continuity of the Self / 2. Mental Continuity / a. Memory is Self
Without memory I could not even speak of myself [Augustine]
16. Persons / F. Free Will / 6. Determinism / a. Determinism
If the future does not exist, how can prophets see it? [Augustine]
18. Thought / B. Mechanics of Thought / 5. Mental Files
Memories are preserved separately, according to category [Augustine]
18. Thought / E. Abstraction / 1. Abstract Thought
'Abstract' nowadays means outside space and time, not concrete, not physical [Brown,JR]
The older sense of 'abstract' is where 'redness' or 'group' is abstracted from particulars [Brown,JR]
19. Language / A. Nature of Meaning / 7. Meaning Holism / c. Meaning by Role
A term can have not only a sense and a reference, but also a 'computational role' [Brown,JR]
22. Metaethics / C. The Good / 2. Happiness / c. Value of happiness
Everyone wants happiness [Augustine]
26. Natural Theory / A. Speculations on Nature / 5. Infinite in Nature
Given atomism at one end, and a finite universe at the other, there are no physical infinities [Brown,JR]
27. Natural Reality / D. Time / 1. Nature of Time / c. Idealist time
Maybe time is an extension of the mind [Augustine]
To be aware of time it can only exist in the mind, as memory or anticipation [Augustine, by Bardon]
27. Natural Reality / D. Time / 1. Nature of Time / g. Growing block
How can ten days ahead be a short time, if it doesn't exist? [Augustine]
27. Natural Reality / D. Time / 1. Nature of Time / h. Presentism
If the past is no longer, and the future is not yet, how can they exist? [Augustine]
27. Natural Reality / D. Time / 1. Nature of Time / i. Denying time
The whole of the current year is not present, so how can it exist? [Augustine]
27. Natural Reality / D. Time / 2. Passage of Time / a. Experience of time
I know what time is, until someone asks me to explain it [Augustine]
27. Natural Reality / D. Time / 2. Passage of Time / h. Change in time
I disagree with the idea that time is nothing but cosmic movement [Augustine]
27. Natural Reality / E. Cosmology / 3. The Beginning
Heaven and earth must be created, because they are subject to change [Augustine]
28. God / A. Divine Nature / 5. God and Time
If God existed before creation, why would a perfect being desire to change things? [Augustine, by Bardon]
If God is outside time in eternity, can He hear prayers? [Augustine]