Combining Texts

All the ideas for 'On Duties ('De Officiis')', 'The Philosophy of Logical Atomism' and 'Introduction to the Philosophy of Mathematics'

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56 ideas

1. Philosophy / A. Wisdom / 1. Nature of Wisdom
Cicero sees wisdom in terms of knowledge, but earlier Stoics saw it as moral [Cicero, by Long]
1. Philosophy / A. Wisdom / 2. Wise People
Unfortunately we choose a way of life before we are old enough to think clearly [Cicero]
1. Philosophy / E. Nature of Metaphysics / 4. Metaphysics as Science
The business of metaphysics is to describe the world [Russell]
2. Reason / B. Laws of Thought / 6. Ockham's Razor
Reducing entities and premisses makes error less likely [Russell]
3. Truth / B. Truthmakers / 5. What Makes Truths / a. What makes truths
Facts make propositions true or false, and are expressed by whole sentences [Russell]
3. Truth / B. Truthmakers / 8. Making General Truths
Not only atomic truths, but also general and negative truths, have truth-makers [Russell, by Rami]
4. Formal Logic / E. Nonclassical Logics / 2. Intuitionist Logic
Rejecting double negation elimination undermines reductio proofs [Colyvan]
Showing a disproof is impossible is not a proof, so don't eliminate double negation [Colyvan]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / c. Unit (Singleton) Sets
Normally a class with only one member is a problem, because the class and the member are identical [Russell]
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
Excluded middle says P or not-P; bivalence says P is either true or false [Colyvan]
5. Theory of Logic / E. Structures of Logic / 1. Logical Form
In a logically perfect language, there will be just one word for every simple object [Russell]
Romulus does not occur in the proposition 'Romulus did not exist' [Russell]
5. Theory of Logic / F. Referring in Logic / 1. Naming / a. Names
You can understand 'author of Waverley', but to understand 'Scott' you must know who it applies to [Russell]
There are a set of criteria for pinning down a logically proper name [Russell, by Sainsbury]
5. Theory of Logic / F. Referring in Logic / 1. Naming / b. Names as descriptive
Treat description using quantifiers, and treat proper names as descriptions [Russell, by McCullogh]
5. Theory of Logic / F. Referring in Logic / 1. Naming / e. Empty names
A name has got to name something or it is not a name [Russell]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
Löwenheim proved his result for a first-order sentence, and Skolem generalised it [Colyvan]
5. Theory of Logic / K. Features of Logics / 1. Axiomatisation
Axioms are 'categorical' if all of their models are isomorphic [Colyvan]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
Ordinal numbers represent order relations [Colyvan]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
Intuitionists only accept a few safe infinities [Colyvan]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / j. Infinite divisibility
Infinitesimals were sometimes zero, and sometimes close to zero [Colyvan]
6. Mathematics / B. Foundations for Mathematics / 1. Foundations for Mathematics
Reducing real numbers to rationals suggested arithmetic as the foundation of maths [Colyvan]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / f. Mathematical induction
Transfinite induction moves from all cases, up to the limit ordinal [Colyvan]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Most mathematical proofs are using set theory, but without saying so [Colyvan]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / a. Structuralism
Structuralism say only 'up to isomorphism' matters because that is all there is to it [Colyvan]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / e. Structuralism critique
If 'in re' structures relies on the world, does the world contain rich enough structures? [Colyvan]
6. Mathematics / C. Sources of Mathematics / 9. Fictional Mathematics
Numbers are classes of classes, and hence fictions of fictions [Russell]
7. Existence / C. Structure of Existence / 6. Fundamentals / d. Logical atoms
Russell's new logical atomist was of particulars, universals and facts (not platonic propositions) [Russell, by Linsky,B]
Russell's atomic facts are actually compounds, and his true logical atoms are sense data [Russell, by Quine]
Logical atomism aims at logical atoms as the last residue of analysis [Russell]
Once you have enumerated all the atomic facts, there is a further fact that those are all the facts [Russell]
Logical atoms aims to get down to ultimate simples, with their own unique reality [Russell]
7. Existence / D. Theories of Reality / 8. Facts / a. Facts
You can't name all the facts, so they are not real, but are what propositions assert [Russell]
7. Existence / D. Theories of Reality / 8. Facts / b. Types of fact
Russell asserts atomic, existential, negative and general facts [Russell, by Armstrong]
7. Existence / D. Theories of Reality / 9. States of Affairs
Modern trope theory tries, like logical atomism, to reduce things to elementary states [Russell, by Ellis]
7. Existence / D. Theories of Reality / 11. Ontological Commitment / a. Ontological commitment
'Existence' means that a propositional function is sometimes true [Russell]
10. Modality / A. Necessity / 2. Nature of Necessity
Modal terms are properties of propositional functions, not of propositions [Russell]
12. Knowledge Sources / B. Perception / 5. Interpretation
Perception goes straight to the fact, and not through the proposition [Russell]
14. Science / C. Induction / 6. Bayes's Theorem
Probability supports Bayesianism better as degrees of belief than as ratios of frequencies [Colyvan]
14. Science / D. Explanation / 2. Types of Explanation / e. Lawlike explanations
Mathematics can reveal structural similarities in diverse systems [Colyvan]
14. Science / D. Explanation / 2. Types of Explanation / f. Necessity in explanations
Mathematics can show why some surprising events have to occur [Colyvan]
14. Science / D. Explanation / 2. Types of Explanation / m. Explanation by proof
Proof by cases (by 'exhaustion') is said to be unexplanatory [Colyvan]
Reductio proofs do not seem to be very explanatory [Colyvan]
If inductive proofs hold because of the structure of natural numbers, they may explain theorems [Colyvan]
Can a proof that no one understands (of the four-colour theorem) really be a proof? [Colyvan]
15. Nature of Minds / C. Capacities of Minds / 5. Generalisation by mind
Mathematical generalisation is by extending a system, or by abstracting away from it [Colyvan]
18. Thought / A. Modes of Thought / 6. Judgement / b. Error
The theory of error seems to need the existence of the non-existent [Russell]
19. Language / C. Assigning Meanings / 3. Predicates
Russell uses 'propositional function' to refer to both predicates and to attributes [Quine on Russell]
19. Language / D. Propositions / 1. Propositions
Propositions don't name facts, because each fact corresponds to a proposition and its negation [Russell]
19. Language / D. Propositions / 3. Concrete Propositions
In 1918 still believes in nonlinguistic analogues of sentences, but he now calls them 'facts' [Russell, by Quine]
19. Language / D. Propositions / 6. Propositions Critique
An inventory of the world does not need to include propositions [Russell]
I no longer believe in propositions, especially concerning falsehoods [Russell]
I know longer believe in shadowy things like 'that today is Wednesday' when it is actually Tuesday [Russell]
19. Language / F. Communication / 4. Private Language
The names in a logically perfect language would be private, and could not be shared [Russell]
23. Ethics / D. Deontological Ethics / 3. Universalisability
The essence of propriety is consistency [Cicero]
28. God / B. Proving God / 2. Proofs of Reason / b. Ontological Proof critique
You can discuss 'God exists', so 'God' is a description, not a name [Russell]