Combining Philosophers

All the ideas for Euclid, Jacques Lenfant and Gideon Rosen

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42 ideas

1. Philosophy / F. Analytic Philosophy / 5. Linguistic Analysis
Philosophers are often too fussy about words, dismissing perfectly useful ordinary terms [Rosen]
2. Reason / D. Definition / 1. Definitions
Figuring in the definition of a thing doesn't make it a part of that thing [Rosen]
2. Reason / E. Argument / 6. Conclusive Proof
Proof reveals the interdependence of truths, as well as showing their certainty [Euclid, by Frege]
4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / c. Derivations rules of PC
If you pick an arbitrary triangle, things proved of it are true of all triangles [Euclid, by Lemmon]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / c. Axiom of Pairing II
Pairing (with Extensionality) guarantees an infinity of sets, just from a single element [Rosen]
5. Theory of Logic / K. Features of Logics / 10. Monotonicity
Explanations fail to be monotonic [Rosen]
6. Mathematics / A. Nature of Mathematics / 2. Geometry
Euclid's geometry is synthetic, but Descartes produced an analytic version of it [Euclid, by Resnik]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
An assumption that there is a largest prime leads to a contradiction [Euclid, by Brown,JR]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / m. One
A unit is that according to which each existing thing is said to be one [Euclid]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
Postulate 2 says a line can be extended continuously [Euclid, by Shapiro]
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Geometry
Euclid relied on obvious properties in diagrams, as well as on his axioms [Potter on Euclid]
Euclid's parallel postulate defines unique non-intersecting parallel lines [Euclid, by Friend]
Euclid needs a principle of continuity, saying some lines must intersect [Shapiro on Euclid]
Euclid says we can 'join' two points, but Hilbert says the straight line 'exists' [Euclid, by Bernays]
Modern geometries only accept various parts of the Euclid propositions [Russell on Euclid]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / b. Greek arithmetic
Euclid's common notions or axioms are what we must have if we are to learn anything at all [Euclid, by Roochnik]
7. Existence / C. Structure of Existence / 1. Grounding / a. Nature of grounding
Things could be true 'in virtue of' others as relations between truths, or between truths and items [Rosen]
7. Existence / D. Theories of Reality / 8. Facts / a. Facts
Facts are structures of worldly items, rather like sentences, individuated by their ingredients [Rosen]
8. Modes of Existence / B. Properties / 4. Intrinsic Properties
An 'intrinsic' property is one that depends on a thing and its parts, and not on its relations [Rosen]
8. Modes of Existence / C. Powers and Dispositions / 4. Powers as Essence
The question is whether force is self-sufficient in bodies, and essential, or dependent on something [Lenfant]
9. Objects / A. Existence of Objects / 2. Abstract Objects / d. Problems with abstracta
How we refer to abstractions is much less clear than how we refer to other things [Rosen]
9. Objects / A. Existence of Objects / 4. Impossible objects
A Meinongian principle might say that there is an object for any modest class of properties [Rosen]
10. Modality / A. Necessity / 5. Metaphysical Necessity
Metaphysical necessity is absolute and universal; metaphysical possibility is very tolerant [Rosen]
'Metaphysical' modality is the one that makes the necessity or contingency of laws of nature interesting [Rosen]
Sets, universals and aggregates may be metaphysically necessary in one sense, but not another [Rosen]
The excellent notion of metaphysical 'necessity' cannot be defined [Rosen]
Standard Metaphysical Necessity: P holds wherever the actual form of the world holds [Rosen]
Non-Standard Metaphysical Necessity: when ¬P is incompatible with the nature of things [Rosen]
10. Modality / A. Necessity / 6. Logical Necessity
Something may be necessary because of logic, but is that therefore a special sort of necessity? [Rosen]
10. Modality / B. Possibility / 3. Combinatorial possibility
Combinatorial theories of possibility assume the principles of combination don't change across worlds [Rosen]
10. Modality / C. Sources of Modality / 1. Sources of Necessity
Are necessary truths rooted in essences, or also in basic grounding laws? [Rosen]
10. Modality / D. Knowledge of Modality / 4. Conceivable as Possible / a. Conceivable as possible
A proposition is 'correctly' conceivable if an ominiscient being could conceive it [Rosen]
18. Thought / E. Abstraction / 2. Abstracta by Selection
The Way of Abstraction used to say an abstraction is an idea that was formed by abstracting [Rosen]
18. Thought / E. Abstraction / 5. Abstracta by Negation
Nowadays abstractions are defined as non-spatial, causally inert things [Rosen]
Chess may be abstract, but it has existed in specific space and time [Rosen]
Sets are said to be abstract and non-spatial, but a set of books can be on a shelf [Rosen]
18. Thought / E. Abstraction / 6. Abstracta by Conflation
Conflating abstractions with either sets or universals is a big claim, needing a big defence [Rosen]
18. Thought / E. Abstraction / 7. Abstracta by Equivalence
Functional terms can pick out abstractions by asserting an equivalence relation [Rosen]
Abstraction by equivalence relationships might prove that a train is an abstract entity [Rosen]
19. Language / E. Analyticity / 1. Analytic Propositions
'Bachelor' consists in or reduces to 'unmarried' male, but not the other way around [Rosen]
26. Natural Theory / D. Laws of Nature / 4. Regularities / b. Best system theory
The MRL view says laws are the theorems of the simplest and strongest account of the world [Rosen]
27. Natural Reality / F. Chemistry / 1. Chemistry
An acid is just a proton donor [Rosen]