Combining Philosophers

All the ideas for Xenophanes, GE Hughes/M Cresswell and Sarah Sawyer

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15 ideas

4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / b. Terminology of PL
A 'value-assignment' (V) is when to each variable in the set V assigns either the value 1 or the value 0 [Hughes/Cresswell]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / d. Basic theorems of PL
The Law of Transposition says (P→Q) → (¬Q→¬P) [Hughes/Cresswell]
4. Formal Logic / B. Propositional Logic PL / 4. Soundness of PL
The rules preserve validity from the axioms, so no thesis negates any other thesis [Hughes/Cresswell]
5. Theory of Logic / F. Referring in Logic / 1. Naming / a. Names
Semantic theory should specify when an act of naming is successful [Sawyer]
5. Theory of Logic / F. Referring in Logic / 1. Naming / c. Names as referential
Millians say a name just means its object [Sawyer]
5. Theory of Logic / F. Referring in Logic / 1. Naming / e. Empty names
Sentences with empty names can be understood, be co-referential, and even be true [Sawyer]
Frege's compositional account of truth-vaues makes 'Pegasus doesn't exist' neither true nor false [Sawyer]
5. Theory of Logic / F. Referring in Logic / 2. Descriptions / c. Theory of definite descriptions
Definites descriptions don't solve the empty names problem, because the properties may not exist [Sawyer]
5. Theory of Logic / K. Features of Logics / 4. Completeness
A system is 'weakly' complete if all wffs are derivable, and 'strongly' if theses are maximised [Hughes/Cresswell]
13. Knowledge Criteria / D. Scepticism / 1. Scepticism
If we succeed in speaking the truth, we cannot know we have done it [Xenophanes]
13. Knowledge Criteria / E. Relativism / 1. Relativism
If God had not created honey, men would say figs are sweeter [Xenophanes]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / e. The One
The basic Eleatic belief was that all things are one [Xenophanes, by Plato]
28. God / A. Divine Nature / 2. Divine Nature
Xenophanes said the essence of God was spherical and utterly inhuman [Xenophanes, by Diog. Laertius]
28. God / C. Attitudes to God / 5. Atheism
Mortals believe gods are born, and have voices and clothes just like mortals [Xenophanes]
Ethiopian gods have black hair, and Thracian gods have red hair [Xenophanes]