Combining Texts

All the ideas for 'Classical Cosmology (frags)', 'Monadology' and 'Alfred Tarski: life and logic'

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32 ideas

2. Reason / B. Laws of Thought / 2. Sufficient Reason
No fact can be real and no proposition true unless there is a Sufficient Reason (even if we can't know it) [Leibniz]
3. Truth / D. Coherence Truth / 1. Coherence Truth
Everything in the universe is interconnected, so potentially a mind could know everything [Leibniz]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
The Axiom of Choice is consistent with the other axioms of set theory [Feferman/Feferman]
Axiom of Choice: a set exists which chooses just one element each of any set of sets [Feferman/Feferman]
Platonist will accept the Axiom of Choice, but others want criteria of selection or definition [Feferman/Feferman]
The Trichotomy Principle is equivalent to the Axiom of Choice [Feferman/Feferman]
Cantor's theories needed the Axiom of Choice, but it has led to great controversy [Feferman/Feferman]
5. Theory of Logic / D. Assumptions for Logic / 3. Contradiction
Falsehood involves a contradiction, and truth is contradictory of falsehood [Leibniz]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
A structure is a 'model' when the axioms are true. So which of the structures are models? [Feferman/Feferman]
Tarski and Vaught established the equivalence relations between first-order structures [Feferman/Feferman]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
Löwenheim-Skolem Theorem, and Gödel's completeness of first-order logic, the earliest model theory [Feferman/Feferman]
Löwenheim-Skolem says if the sentences are countable, so is the model [Feferman/Feferman]
5. Theory of Logic / K. Features of Logics / 4. Completeness
If a sentence holds in every model of a theory, then it is logically derivable from the theory [Feferman/Feferman]
5. Theory of Logic / K. Features of Logics / 7. Decidability
'Recursion theory' concerns what can be solved by computing machines [Feferman/Feferman]
Both Principia Mathematica and Peano Arithmetic are undecidable [Feferman/Feferman]
7. Existence / C. Structure of Existence / 6. Fundamentals / c. Monads
The monad idea incomprehensibly spiritualises matter, instead of materialising soul [La Mettrie on Leibniz]
He replaced Aristotelian continuants with monads [Leibniz, by Wiggins]
Is a drop of urine really an infinity of thinking monads? [Voltaire on Leibniz]
It is unclear in 'Monadology' how extended bodies relate to mind-like monads. [Garber on Leibniz]
Changes in a monad come from an internal principle, and the diversity within its substance [Leibniz]
A 'monad' has basic perception and appetite; a 'soul' has distinct perception and memory [Leibniz]
9. Objects / B. Unity of Objects / 2. Substance / e. Substance critique
If a substance is just a thing that has properties, it seems to be a characterless non-entity [Leibniz, by Macdonald,C]
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
There must be some internal difference between any two beings in nature [Leibniz]
10. Modality / D. Knowledge of Modality / 1. A Priori Necessary
Truths of reason are known by analysis, and are necessary; facts are contingent, and their opposites possible [Leibniz]
12. Knowledge Sources / A. A Priori Knowledge / 4. A Priori as Necessities
Mathematical analysis ends in primitive principles, which cannot be and need not be demonstrated [Leibniz]
12. Knowledge Sources / C. Rationalism / 1. Rationalism
We all expect the sun to rise tomorrow by experience, but astronomers expect it by reason [Leibniz]
15. Nature of Minds / B. Features of Minds / 3. Privacy
Increase a conscious machine to the size of a mill - you still won't see perceptions in it [Leibniz]
16. Persons / C. Self-Awareness / 2. Knowing the Self
We know the 'I' and its contents by abstraction from awareness of necessary truths [Leibniz]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / f. Ancient elements
The true elements are atomic monads [Leibniz]
27. Natural Reality / E. Cosmology / 1. Cosmology
Is the cosmos open or closed, mechanical or teleological, alive or inanimate, and created or eternal? [Robinson,TM, by PG]
28. God / A. Divine Nature / 3. Divine Perfections
This is the most perfect possible universe, in its combination of variety with order [Leibniz]
28. God / B. Proving God / 2. Proofs of Reason / a. Ontological Proof
God alone (the Necessary Being) has the privilege that He must exist if He is possible [Leibniz]