Combining Texts

All the ideas for 'The Roots of Reference', 'That Politics may be reduced to a Science' and 'What are Sets and What are they For?'

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14 ideas

4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
The empty set is something, not nothing! [Oliver/Smiley]
The empty set is usually derived from Separation, but it also seems to need Infinity [Oliver/Smiley]
We don't need the empty set to express non-existence, as there are other ways to do that [Oliver/Smiley]
Maybe we can treat the empty set symbol as just meaning an empty term [Oliver/Smiley]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / c. Unit (Singleton) Sets
The unit set may be needed to express intersections that leave a single member [Oliver/Smiley]
5. Theory of Logic / G. Quantification / 6. Plural Quantification
If you only refer to objects one at a time, you need sets in order to refer to a plurality [Oliver/Smiley]
We can use plural language to refer to the set theory domain, to avoid calling it a 'set' [Oliver/Smiley]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
Logical truths are true no matter what exists - but predicate calculus insists that something exists [Oliver/Smiley]
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / g. Applying mathematics
If mathematics purely concerned mathematical objects, there would be no applied mathematics [Oliver/Smiley]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Sets might either represent the numbers, or be the numbers, or replace the numbers [Oliver/Smiley]
8. Modes of Existence / C. Powers and Dispositions / 3. Powers as Derived
Dispositions are physical states of mechanism; when known, these replace the old disposition term [Quine]
23. Ethics / C. Virtue Theory / 4. External Goods / d. Friendship
Friendship without community spirit misses out on the main part of virtue [Hume]
24. Political Theory / B. Nature of a State / 3. Constitutions
It would be absurd if even a free constitution did not impose restraints, for the public good [Hume]
24. Political Theory / C. Ruling a State / 2. Leaders / d. Elites
Nobility either share in the power of the whole, or they compose the power of the whole [Hume]