Combining Texts

All the ideas for 'On the Natural Faculties', 'The Passions' and 'A Tour through Mathematical Logic'

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46 ideas

1. Philosophy / A. Wisdom / 1. Nature of Wisdom
Wisdom needs both thought and passion, with each reflecting on the other [Solomon]
1. Philosophy / E. Nature of Metaphysics / 3. Metaphysical Systems
Philosophy is creating an intellectual conceptual structure for life [Solomon]
2. Reason / A. Nature of Reason / 1. On Reason
Reason is actually passions, guided by perspicacious reflection [Solomon]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / b. Terminology of PL
A 'tautology' must include connectives [Wolf,RS]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / c. Derivation rules of PL
Deduction Theorem: T∪{P}|-Q, then T|-(P→Q), which justifies Conditional Proof [Wolf,RS]
4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / d. Universal quantifier ∀
Universal Generalization: If we prove P(x) with no special assumptions, we can conclude ∀xP(x) [Wolf,RS]
Universal Specification: ∀xP(x) implies P(t). True for all? Then true for an instance [Wolf,RS]
4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / e. Existential quantifier ∃
Existential Generalization (or 'proof by example'): if we can say P(t), then we can say something is P [Wolf,RS]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / e. Axiom of the Empty Set IV
Empty Set: ∃x∀y ¬(y∈x). The unique empty set exists [Wolf,RS]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / n. Axiom of Comprehension
Comprehension Axiom: if a collection is clearly specified, it is a set [Wolf,RS]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
In first-order logic syntactic and semantic consequence (|- and |=) nicely coincide [Wolf,RS]
First-order logic is weakly complete (valid sentences are provable); we can't prove every sentence or its negation [Wolf,RS]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
Model theory reveals the structures of mathematics [Wolf,RS]
Model theory 'structures' have a 'universe', some 'relations', some 'functions', and some 'constants' [Wolf,RS]
Model theory uses sets to show that mathematical deduction fits mathematical truth [Wolf,RS]
First-order model theory rests on completeness, compactness, and the Löwenheim-Skolem-Tarski theorem [Wolf,RS]
5. Theory of Logic / J. Model Theory in Logic / 2. Isomorphisms
An 'isomorphism' is a bijection that preserves all structural components [Wolf,RS]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
The LST Theorem is a serious limitation of first-order logic [Wolf,RS]
5. Theory of Logic / K. Features of Logics / 4. Completeness
If a theory is complete, only a more powerful language can strengthen it [Wolf,RS]
5. Theory of Logic / K. Features of Logics / 10. Monotonicity
Most deductive logic (unlike ordinary reasoning) is 'monotonic' - we don't retract after new givens [Wolf,RS]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
An ordinal is an equivalence class of well-orderings, or a transitive set whose members are transitive [Wolf,RS]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Modern mathematics has unified all of its objects within set theory [Wolf,RS]
12. Knowledge Sources / E. Direct Knowledge / 2. Intuition
We often trust our intuitions as rational, despite their lack of reflection [Solomon]
15. Nature of Minds / C. Capacities of Minds / 1. Faculties
We just use the word 'faculty' when we don't know the psychological cause [Galen]
Distinguishing reason from passion is based on an archaic 'faculty' theory [Solomon]
18. Thought / A. Modes of Thought / 3. Emotions / a. Nature of emotions
I say bodily chemistry and its sensations have nothing to do with emotions [Solomon]
Emotions are judgements about ourselves, and our place in the world [Solomon]
Emotions are defined by their objects [Solomon]
The heart of an emotion is its judgement of values and morality [Solomon]
Emotions can be analysed under fifteen headings [Solomon]
18. Thought / A. Modes of Thought / 3. Emotions / b. Types of emotion
Some emotions are externally directed, others internally [Solomon]
18. Thought / A. Modes of Thought / 3. Emotions / c. Role of emotions
It is only our passions which give our lives meaning [Solomon]
Which emotions we feel depends on our sense of our own powers [Solomon]
The passions are subjective, concerning what is important to me, rather than facts [Solomon]
Emotions are strategies for maximising our sense of dignity and self-esteem [Solomon]
Passions exist as emotions, moods and desires, which all generate meaning [Solomon]
The Myth of the Passions says they are irrational, uncontrolled and damaging [Solomon]
18. Thought / A. Modes of Thought / 3. Emotions / d. Emotional feeling
Feeling is a superficial aspect of emotion, and may be indeterminate, or even absent [Solomon]
18. Thought / A. Modes of Thought / 3. Emotions / e. Basic emotions
There are no 'basic' emotions, only socially prevalent ones [Solomon]
18. Thought / A. Modes of Thought / 3. Emotions / f. Emotion and reason
It is reason which needs the anchorage of passions, rather than vice versa [Solomon]
Dividing ourselves into confrontational reason and passion destroys our harmonious whole [Solomon]
The supposed irrationality of our emotions is often tactless or faulty expression of them [Solomon]
22. Metaethics / B. Value / 1. Nature of Value / d. Subjective value
Emotions are our life force, and the source of most of our values [Solomon]
22. Metaethics / B. Value / 2. Values / g. Love
Lovers adopt the interests of their beloved, rather than just valuing them [Solomon]
23. Ethics / F. Existentialism / 2. Nihilism
'Absurdity' is just the result of our wrong choices in life [Solomon]
24. Political Theory / D. Ideologies / 1. Ideology
Ideologies are mythologies which guide our actions [Solomon]