Combining Texts

All the ideas for 'fragments/reports', 'Investigations in the Foundations of Set Theory I' and 'Our Knowledge of the External World'

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37 ideas

1. Philosophy / A. Wisdom / 1. Nature of Wisdom
A sense of timelessness is essential to wisdom [Russell]
1. Philosophy / D. Nature of Philosophy / 7. Despair over Philosophy
Philosophical disputes are mostly hopeless, because philosophers don't understand each other [Russell]
1. Philosophy / E. Nature of Metaphysics / 3. Metaphysical Systems
Philosophical systems are interesting, but we now need a more objective scientific philosophy [Russell]
Hegel's confusions over 'is' show how vast systems can be built on simple errors [Russell]
Philosophers sometimes neglect truth and distort facts to attain a nice system [Russell]
1. Philosophy / E. Nature of Metaphysics / 4. Metaphysics as Science
Physicists accept particles, points and instants, while pretending they don't do metaphysics [Russell]
1. Philosophy / F. Analytic Philosophy / 6. Logical Analysis
When problems are analysed properly, they are either logical, or not philosophical at all [Russell]
2. Reason / D. Definition / 8. Impredicative Definition
Predicative definitions are acceptable in mathematics if they distinguish objects, rather than creating them? [Zermelo, by Lavine]
4. Formal Logic / F. Set Theory ST / 1. Set Theory
We take set theory as given, and retain everything valuable, while avoiding contradictions [Zermelo]
Set theory investigates number, order and function, showing logical foundations for mathematics [Zermelo]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
ZFC: Existence, Extension, Specification, Pairing, Unions, Powers, Infinity, Choice [Zermelo, by Clegg]
Zermelo published his axioms in 1908, to secure a controversial proof [Zermelo, by Maddy]
Set theory can be reduced to a few definitions and seven independent axioms [Zermelo]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / c. Axiom of Pairing II
Zermelo introduced Pairing in 1930, and it seems fairly obvious [Zermelo, by Maddy]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / i. Axiom of Foundation VIII
Zermelo used Foundation to block paradox, but then decided that only Separation was needed [Zermelo, by Maddy]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / m. Axiom of Separation
The Axiom of Separation requires set generation up to one step back from contradiction [Zermelo, by Maddy]
Not every predicate has an extension, but Separation picks the members that satisfy a predicate [Zermelo, by Hart,WD]
5. Theory of Logic / A. Overview of Logic / 3. Value of Logic
Logic gives the method of research in philosophy [Russell]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
The logical connectives are not objects, but are formal, and need a context [Russell]
5. Theory of Logic / L. Paradox / 4. Paradoxes in Logic / a. Achilles paradox
The tortoise won't win, because infinite instants don't compose an infinitely long time [Russell]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
In ZF, the Burali-Forti Paradox proves that there is no set of all ordinals [Zermelo, by Hart,WD]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / f. Zermelo numbers
For Zermelo the successor of n is {n} (rather than n U {n}) [Zermelo, by Maddy]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Zermelo believed, and Von Neumann seemed to confirm, that numbers are sets [Zermelo, by Maddy]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / e. Structuralism critique
Different versions of set theory result in different underlying structures for numbers [Zermelo, by Brown,JR]
7. Existence / C. Structure of Existence / 6. Fundamentals / d. Logical atoms
Atomic facts may be inferrable from others, but never from non-atomic facts [Russell]
7. Existence / D. Theories of Reality / 8. Facts / d. Negative facts
A positive and negative fact have the same constituents; their difference is primitive [Russell]
8. Modes of Existence / A. Relations / 1. Nature of Relations
With asymmetrical relations (before/after) the reduction to properties is impossible [Russell]
8. Modes of Existence / B. Properties / 11. Properties as Sets
When we attribute a common quality to a group, we can forget the quality and just talk of the group [Russell]
11. Knowledge Aims / C. Knowing Reality / 1. Perceptual Realism / c. Representative realism
Science condemns sense-data and accepts matter, but a logical construction must link them [Russell]
12. Knowledge Sources / B. Perception / 4. Sense Data / c. Unperceived sense-data
When sense-data change, there must be indistinguishable sense-data in the process [Russell]
12. Knowledge Sources / C. Rationalism / 1. Rationalism
Empirical truths are particular, so general truths need an a priori input of generality [Russell]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / b. Pro-coherentism
Objects are treated as real when they connect with other experiences in a normal way [Russell]
13. Knowledge Criteria / D. Scepticism / 6. Scepticism Critique
Global scepticism is irrefutable, but can't replace our other beliefs, and just makes us hesitate [Russell]
15. Nature of Minds / A. Nature of Mind / 1. Mind / d. Location of mind
Alcmaeon was the first to say the brain is central to thinking [Alcmaeon, by Staden, von]
15. Nature of Minds / A. Nature of Mind / 4. Other Minds / c. Knowing other minds
Other minds seem to exist, because their testimony supports realism about the world [Russell, by Grayling]
27. Natural Reality / D. Time / 2. Passage of Time / a. Experience of time
We never experience times, but only succession of events [Russell]
29. Religion / D. Religious Issues / 2. Immortality / b. Soul
Soul must be immortal, since it continually moves, like the heavens [Alcmaeon, by Aristotle]