Combining Philosophers

All the ideas for Xenophanes, Engelbretsen,G/Sayward,C and Jean Buridan

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20 ideas

2. Reason / A. Nature of Reason / 9. Limits of Reason
1403 A rational donkey would starve to death between two totally identical piles of hay [Buridan, by PG]
4. Formal Logic / A. Syllogistic Logic / 1. Aristotelian Logic
13913 The four 'perfect syllogisms' are called Barbara, Celarent, Darii and Ferio [Engelbretsen/Sayward]
13914 Syllogistic logic has one rule: what is affirmed/denied of wholes is affirmed/denied of their parts [Engelbretsen/Sayward]
4. Formal Logic / A. Syllogistic Logic / 2. Syllogistic Logic
13915 Syllogistic can't handle sentences with singular terms, or relational terms, or compound sentences [Engelbretsen/Sayward]
4. Formal Logic / A. Syllogistic Logic / 3. Term Logic
13916 Term logic uses expression letters and brackets, and '-' for negative terms, and '+' for compound terms [Engelbretsen/Sayward]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
13850 In modern logic all formal validity can be characterised syntactically [Engelbretsen/Sayward]
5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
13849 Classical logic rests on truth and models, where constructivist logic rests on defence and refutation [Engelbretsen/Sayward]
5. Theory of Logic / D. Assumptions for Logic / 4. Identity in Logic
13851 Unlike most other signs, = cannot be eliminated [Engelbretsen/Sayward]
5. Theory of Logic / K. Features of Logics / 5. Incompleteness
13852 Axioms are ω-incomplete if the instances are all derivable, but the universal quantification isn't [Engelbretsen/Sayward]
9. Objects / C. Structure of Objects / 4. Quantity of an Object
16678 Without magnitude a thing would retain its parts, but they would have no location [Buridan]
9. Objects / E. Objects over Time / 8. Continuity of Rivers
16793 A thing is (less properly) the same over time if each part is succeeded by another [Buridan]
12. Knowledge Sources / B. Perception / 2. Qualities in Perception / b. Primary/secondary
16726 Why can't we deduce secondary qualities from primary ones, if they cause them? [Buridan]
13. Knowledge Criteria / D. Scepticism / 1. Scepticism
411 If we succeed in speaking the truth, we cannot know we have done it [Xenophanes]
13. Knowledge Criteria / E. Relativism / 1. Relativism
412 If God had not created honey, men would say figs are sweeter [Xenophanes]
14. Science / A. Basis of Science / 2. Demonstration
16577 Induction is not demonstration, because not all of the instances can be observed [Buridan]
14. Science / C. Induction / 2. Aims of Induction
16576 Science is based on induction, for general truths about fire, rhubarb and magnets [Buridan]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / e. The One
1640 The basic Eleatic belief was that all things are one [Xenophanes, by Plato]
28. God / A. Divine Nature / 2. Divine Nature
3055 Xenophanes said the essence of God was spherical and utterly inhuman [Xenophanes, by Diog. Laertius]
28. God / C. Attitudes to God / 5. Atheism
408 Ethiopian gods have black hair, and Thracian gods have red hair [Xenophanes]
407 Mortals believe gods are born, and have voices and clothes just like mortals [Xenophanes]