Combining Texts

All the ideas for 'Thinking About Mathematics', 'Mere Possibilities' and 'Against the Physicists (two books)'

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


62 ideas

1. Philosophy / E. Nature of Metaphysics / 1. Nature of Metaphysics
I don't think Lewis's cost-benefit reflective equilibrium approach offers enough guidance [Stalnaker]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / a. Systems of modal logic
Non-S5 can talk of contingent or necessary necessities [Stalnaker]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / b. Axiom of Extensionality I
In modal set theory, sets only exist in a possible world if that world contains all of its members [Stalnaker]
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
Intuitionists deny excluded middle, because it is committed to transcendent truth or objects [Shapiro]
5. Theory of Logic / E. Structures of Logic / 1. Logical Form
We regiment to get semantic structure, for evaluating arguments, and understanding complexities [Stalnaker]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / e. or
In 'S was F or some other than S was F', the disjuncts need S, but the whole disjunction doesn't [Stalnaker]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
The number 3 is presumably identical as a natural, an integer, a rational, a real, and complex [Shapiro]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / h. Reals from Cauchy
Cauchy gave a formal definition of a converging sequence. [Shapiro]
6. Mathematics / B. Foundations for Mathematics / 1. Foundations for Mathematics
Categories are the best foundation for mathematics [Shapiro]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / f. Zermelo numbers
Two definitions of 3 in terms of sets disagree over whether 1 is a member of 3 [Shapiro]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / a. Structuralism
Numbers do not exist independently; the essence of a number is its relations to other numbers [Shapiro]
A 'system' is related objects; a 'pattern' or 'structure' abstracts the pure relations from them [Shapiro]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
Logicism seems to be a non-starter if (as is widely held) logic has no ontology of its own [Shapiro]
6. Mathematics / C. Sources of Mathematics / 7. Formalism
Term Formalism says mathematics is just about symbols - but real numbers have no names [Shapiro]
Game Formalism is just a matter of rules, like chess - but then why is it useful in science? [Shapiro]
Deductivism says mathematics is logical consequences of uninterpreted axioms [Shapiro]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / b. Intuitionism
Critics resent the way intuitionism cripples mathematics, but it allows new important distinctions [Shapiro]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / c. Conceptualism
Conceptualist are just realists or idealist or nominalists, depending on their view of concepts [Shapiro]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / d. Predicativism
'Impredicative' definitions refer to the thing being described [Shapiro]
7. Existence / A. Nature of Existence / 1. Nature of Existence
Some say what exists must do so, and nothing else could possible exist [Stalnaker]
A nominalist view says existence is having spatio-temporal location [Stalnaker]
8. Modes of Existence / B. Properties / 1. Nature of Properties
Properties are modal, involving possible situations where they are exemplified [Stalnaker]
8. Modes of Existence / B. Properties / 10. Properties as Predicates
I accept a hierarchy of properties of properties of properties [Stalnaker]
8. Modes of Existence / C. Powers and Dispositions / 6. Dispositions / a. Dispositions
Dispositions have modal properties, of which properties things would have counterfactually [Stalnaker]
9. Objects / C. Structure of Objects / 8. Parts of Objects / c. Wholes from parts
Parts are not parts if their whole is nothing more than the parts [Sext.Empiricus]
9. Objects / D. Essence of Objects / 7. Essence and Necessity / a. Essence as necessary properties
'Socrates is essentially human' seems to say nothing could be Socrates if it was not human [Stalnaker]
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
The bundle theory makes the identity of indiscernibles a necessity, since the thing is the properties [Stalnaker]
10. Modality / A. Necessity / 3. Types of Necessity
Strong necessity is always true; weak necessity is cannot be false [Stalnaker]
10. Modality / C. Sources of Modality / 2. Necessity as Primitive
Necessity and possibility are fundamental, and there can be no reductive analysis of them [Stalnaker]
10. Modality / C. Sources of Modality / 5. Modality from Actuality
Modal concepts are central to the actual world, and shouldn't need extravagant metaphysics [Stalnaker]
10. Modality / E. Possible worlds / 1. Possible Worlds / d. Possible worlds actualism
Given actualism, how can there be possible individuals, other than the actual ones? [Stalnaker]
10. Modality / E. Possible worlds / 2. Nature of Possible Worlds / a. Nature of possible worlds
Possible worlds are properties [Stalnaker]
Possible worlds don't reduce modality, they regiment it to reveal its structure [Stalnaker]
I think of worlds as cells (rather than points) in logical space [Stalnaker]
10. Modality / E. Possible worlds / 3. Transworld Objects / c. Counterparts
Modal properties depend on the choice of a counterpart, which is unconstrained by metaphysics [Stalnaker]
10. Modality / E. Possible worlds / 3. Transworld Objects / d. Haecceitism
Anti-haecceitism says there is no more to an individual than meeting some qualitative conditions [Stalnaker]
12. Knowledge Sources / C. Rationalism / 1. Rationalism
Some say motion is perceived by sense, but others say it is by intellect [Sext.Empiricus]
Rationalism tries to apply mathematical methodology to all of knowledge [Shapiro]
15. Nature of Minds / C. Capacities of Minds / 6. Idealisation
If we try to conceive of a line with no breadth, it ceases to exist, and so has no length [Sext.Empiricus]
17. Mind and Body / D. Property Dualism / 4. Emergentism
The incorporeal is not in the nature of body, and so could not emerge from it [Sext.Empiricus]
18. Thought / C. Content / 6. Broad Content
How can we know what we are thinking, if content depends on something we don't know? [Stalnaker]
19. Language / C. Assigning Meanings / 2. Semantics
We still lack an agreed semantics for quantifiers in natural language [Stalnaker]
19. Language / C. Assigning Meanings / 8. Possible Worlds Semantics
Possible world semantics may not reduce modality, but it can explain it [Stalnaker]
19. Language / D. Propositions / 1. Propositions
I take propositions to be truth conditions [Stalnaker]
A theory of propositions at least needs primitive properties of consistency and of truth [Stalnaker]
19. Language / D. Propositions / 3. Concrete Propositions
Propositions presumably don't exist if the things they refer to don't exist [Stalnaker]
27. Natural Reality / A. Classical Physics / 1. Mechanics / a. Explaining movement
A man walking backwards on a forwards-moving ship is moving in a fixed place [Sext.Empiricus]
27. Natural Reality / D. Time / 2. Passage of Time / c. Tenses and time
Time doesn't end with the Universe, because tensed statements about destruction remain true [Sext.Empiricus]
27. Natural Reality / D. Time / 3. Parts of Time / c. Intervals
Time is divisible, into past, present and future [Sext.Empiricus]
27. Natural Reality / D. Time / 3. Parts of Time / e. Present moment
Socrates either dies when he exists (before his death) or when he doesn't (after his death) [Sext.Empiricus]
If the present is just the limit of the past or the future, it can't exist because they don't exist [Sext.Empiricus]
28. God / A. Divine Nature / 2. Divine Nature
All men agree that God is blessed, imperishable, happy and good [Sext.Empiricus]
God must suffer to understand suffering [Sext.Empiricus]
28. God / A. Divine Nature / 3. Divine Perfections
The Divine must lack the virtues of continence and fortitude, because they are not needed [Sext.Empiricus]
28. God / B. Proving God / 1. Proof of God
God is defended by agreement, order, absurdity of denying God, and refutations [Sext.Empiricus]
28. God / B. Proving God / 2. Proofs of Reason / b. Ontological Proof critique
God's sensations imply change, and hence perishing, which is absurd, so there is no such God [Sext.Empiricus]
God without virtue is absurd, but God's virtues will be better than God [Sext.Empiricus]
28. God / B. Proving God / 3. Proofs of Evidence / b. Teleological Proof
The original substance lacked motion or shape, and was given these by a cause [Sext.Empiricus]
28. God / C. Attitudes to God / 4. God Reflects Humanity
The perfections of God were extrapolations from mankind [Sext.Empiricus]
28. God / C. Attitudes to God / 5. Atheism
Gods were invented as watchers of people's secret actions [Sext.Empiricus]
An incorporeal God could do nothing, and a bodily god would perish, so there is no God [Sext.Empiricus]
29. Religion / A. Polytheistic Religion / 1. Animism
It is mad to think that what is useful to us, like lakes and rivers, are gods [Sext.Empiricus]