Combining Texts

All the ideas for 'Notebooks 1914-1916', 'Introduction to Zermelo's 1930 paper' and 'Absolute Necessities'

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21 ideas

1. Philosophy / F. Analytic Philosophy / 5. Linguistic Analysis
Analysis complicates a statement, but only as far as the complexity of its meaning [Wittgenstein]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
The first-order ZF axiomatisation is highly non-categorical [Hallett,M]
Non-categoricity reveals a sort of incompleteness, with sets existing that the axioms don't reveal [Hallett,M]
4. Formal Logic / F. Set Theory ST / 7. Natural Sets
Zermelo allows ur-elements, to enable the widespread application of set-theory [Hallett,M]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
We can dispense with self-evidence, if language itself prevents logical mistakes [Jeshion on Wittgenstein]
5. Theory of Logic / E. Structures of Logic / 1. Logical Form
A statement's logical form derives entirely from its constituents [Wittgenstein]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
'And' and 'not' are non-referring terms, which do not represent anything [Wittgenstein, by Fogelin]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / g. Continuum Hypothesis
The General Continuum Hypothesis and its negation are both consistent with ZF [Hallett,M]
7. Existence / C. Structure of Existence / 6. Fundamentals / d. Logical atoms
The sense of propositions relies on the world's basic logical structure [Wittgenstein]
10. Modality / A. Necessity / 2. Nature of Necessity
Absolute necessity might be achievable either logically or metaphysically [Hale]
10. Modality / A. Necessity / 3. Types of Necessity
Maybe not-p is logically possible, but p is metaphysically necessary, so the latter is not absolute [Hale]
A strong necessity entails a weaker one, but not conversely; possibilities go the other way [Hale]
'Relative' necessity is just a logical consequence of some statements ('strong' if they are all true) [Hale]
10. Modality / A. Necessity / 5. Metaphysical Necessity
Metaphysical necessity says there is no possibility of falsehood [Hale]
10. Modality / A. Necessity / 6. Logical Necessity
'Broadly' logical necessities are derived (in a structure) entirely from the concepts [Hale]
Logical necessities are true in virtue of the nature of all logical concepts [Hale]
10. Modality / C. Sources of Modality / 4. Necessity from Concepts
Conceptual necessities are made true by all concepts [Hale]
12. Knowledge Sources / A. A Priori Knowledge / 5. A Priori Synthetic
My main problem is the order of the world, and whether it is knowable a priori [Wittgenstein]
16. Persons / B. Nature of the Self / 4. Presupposition of Self
The philosophical I is the metaphysical subject, the limit - not a part of the world [Wittgenstein]
19. Language / A. Nature of Meaning / 2. Meaning as Mental
Propositions assemble a world experimentally, like the model of a road accident [Wittgenstein]
25. Social Practice / F. Life Issues / 4. Suicide
Absolute prohibitions are the essence of ethics, and suicide is the most obvious example [Wittgenstein]