Combining Philosophers

All the ideas for Diogenes Laertius, Hippocrates and Rod Girle

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23 ideas

2. Reason / C. Styles of Reason / 1. Dialectic
Dialectic involves conversations with short questions and brief answers [Diog. Laertius]
4. Formal Logic / B. Propositional Logic PL / 1. Propositional Logic
There are three axiom schemas for propositional logic [Girle]
Propositional logic handles negation, disjunction, conjunction; predicate logic adds quantifiers, predicates, relations [Girle]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / a. Symbols of PL
Proposition logic has definitions for its three operators: or, and, and identical [Girle]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / e. Axioms of PL
Axiom systems of logic contain axioms, inference rules, and definitions of proof and theorems [Girle]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / g. System S4
There are seven modalities in S4, each with its negation [Girle]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / h. System S5
◊p → □◊p is the hallmark of S5 [Girle]
S5 has just six modalities, and all strings can be reduced to those [Girle]
4. Formal Logic / D. Modal Logic ML / 4. Alethic Modal Logic
Possible worlds logics use true-in-a-world rather than true [Girle]
Modal logics were studied in terms of axioms, but now possible worlds semantics is added [Girle]
Modal logic has four basic modal negation equivalences [Girle]
5. Theory of Logic / B. Logical Consequence / 7. Strict Implication
Necessary implication is called 'strict implication'; if successful, it is called 'entailment' [Girle]
5. Theory of Logic / H. Proof Systems / 5. Tableau Proof
If an argument is invalid, a truth tree will indicate a counter-example [Girle]
10. Modality / A. Necessity / 3. Types of Necessity
Analytic truths are divided into logically and conceptually necessary [Girle]
10. Modality / B. Possibility / 1. Possibility
Possibilities can be logical, theoretical, physical, economic or human [Girle]
10. Modality / E. Possible worlds / 1. Possible Worlds / a. Possible worlds
A world has 'access' to a world it generates, which is important in possible worlds semantics [Girle]
13. Knowledge Criteria / A. Justification Problems / 2. Justification Challenges / a. Agrippa's trilemma
Sceptics say demonstration depends on self-demonstrating things, or indemonstrable things [Diog. Laertius]
13. Knowledge Criteria / D. Scepticism / 1. Scepticism
Scepticism has two dogmas: that nothing is definable, and every argument has an opposite argument [Diog. Laertius]
13. Knowledge Criteria / D. Scepticism / 6. Scepticism Critique
When sceptics say that nothing is definable, or all arguments have an opposite, they are being dogmatic [Diog. Laertius]
14. Science / C. Induction / 4. Reason in Induction
Induction moves from some truths to similar ones, by contraries or consequents [Diog. Laertius]
17. Mind and Body / E. Mind as Physical / 1. Physical Mind
All of our happiness and misery arises entirely from the brain [Hippocrates]
22. Metaethics / C. The Good / 3. Pleasure / b. Types of pleasure
Cyrenaic pleasure is a motion, but Epicurean pleasure is a condition [Diog. Laertius]
23. Ethics / A. Egoism / 1. Ethical Egoism
Cynics believe that when a man wishes for nothing he is like the gods [Diog. Laertius]