Combining Philosophers

All the ideas for Agrippa, Max J. Cresswell and Peter Abelard

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21 ideas

2. Reason / A. Nature of Reason / 9. Limits of Reason
1815 Reasoning needs arbitrary faith in preliminary hypotheses (Mode 14) [Agrippa, by Diog. Laertius]
1812 All discussion is full of uncertainty and contradiction (Mode 11) [Agrippa, by Diog. Laertius]
1811 Proofs often presuppose the thing to be proved (Mode 15) [Agrippa, by Diog. Laertius]
1813 All reasoning endlessly leads to further reasoning (Mode 12) [Agrippa, by Diog. Laertius]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / b. System K
14970 Normal system K has five axioms and rules [Cresswell]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / c. System D
14971 D is valid on every serial frame, but not where there are dead ends [Cresswell]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / g. System S4
14972 S4 has 14 modalities, and always reduces to a maximum of three modal operators [Cresswell]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / h. System S5
14973 In S5 all the long complex modalities reduce to just three, and their negations [Cresswell]
4. Formal Logic / D. Modal Logic ML / 7. Barcan Formula
14976 Reject the Barcan if quantifiers are confined to worlds, and different things exist in other worlds [Cresswell]
4. Formal Logic / G. Formal Mereology / 1. Mereology
10397 Abelard's mereology involves privileged and natural divisions, and principal parts [Abelard, by King,P]
8. Modes of Existence / A. Relations / 4. Formal Relations / a. Types of relation
14974 A relation is 'Euclidean' if aRb and aRc imply bRc [Cresswell]
8. Modes of Existence / E. Nominalism / 1. Nominalism / b. Nominalism about universals
10395 Abelard was an irrealist about virtually everything apart from concrete individuals [Abelard, by King,P]
10396 If 'animal' is wholly present in Socrates and an ass, then 'animal' is rational and irrational [Abelard, by King,P]
8. Modes of Existence / E. Nominalism / 3. Predicate Nominalism
15384 Only words can be 'predicated of many'; the universality is just in its mode of signifying [Abelard, by Panaccio]
10. Modality / A. Necessity / 4. De re / De dicto modality
8481 The de dicto-de re modality distinction dates back to Abelard [Abelard, by Orenstein]
14975 A de dicto necessity is true in all worlds, but not necessarily of the same thing in each world [Cresswell]
13. Knowledge Criteria / A. Justification Problems / 2. Justification Challenges / a. Agrippa's trilemma
8850 Agrippa's Trilemma: justification is infinite, or ends arbitrarily, or is circular [Agrippa, by Williams,M]
13. Knowledge Criteria / E. Relativism / 1. Relativism
1814 Everything is perceived in relation to another thing (Mode 13) [Agrippa, by Diog. Laertius]
18. Thought / E. Abstraction / 8. Abstractionism Critique
15385 Abelard's problem is the purely singular aspects of things won't account for abstraction [Panaccio on Abelard]
19. Language / C. Assigning Meanings / 3. Predicates
15383 Nothing external can truly be predicated of an object [Abelard, by Panaccio]
26. Natural Theory / B. Natural Kinds / 7. Critique of Kinds
10398 Natural kinds are not special; they are just well-defined resemblance collections [Abelard, by King,P]