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All the ideas for 'Leibniz', 'Intros to Russell's 'Essays in Analysis'' and 'talk'

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4 ideas

2. Reason / A. Nature of Reason / 9. Limits of Reason
A rational donkey would starve to death between two totally identical piles of hay [Buridan, by PG]
     Full Idea: A rational donkey faced with two totally identical piles of hay would be unable to decide which one to eat first, and would therefore starve to death
     From: report of Jean Buridan (talk [1338]) by PG - Db (ideas)
     A reaction: also De Caelo 295b32 (Idea 19740).
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / b. Cantor's paradox
Sets always exceed terms, so all the sets must exceed all the sets [Lackey]
     Full Idea: Cantor proved that the number of sets in a collection of terms is larger than the number of terms. Hence Cantor's Paradox says the number of sets in the collection of all sets must be larger than the number of sets in the collection of all sets.
     From: Douglas Lackey (Intros to Russell's 'Essays in Analysis' [1973], p.127)
     A reaction: The sets must count as terms in the next iteration, but that is a normal application of the Power Set axiom.
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / c. Burali-Forti's paradox
It seems that the ordinal number of all the ordinals must be bigger than itself [Lackey]
     Full Idea: The ordinal series is well-ordered and thus has an ordinal number, and a series of ordinals to a given ordinal exceeds that ordinal by 1. So the series of all ordinals has an ordinal number that exceeds its own ordinal number by 1.
     From: Douglas Lackey (Intros to Russell's 'Essays in Analysis' [1973], p.127)
     A reaction: Formulated by Burali-Forti in 1897.
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
The Identity of Indiscernibles is really the same as the verification principle [Jolley]
     Full Idea: Various writers have noted that the Identity of Indiscernibles is really tantamount to the verification principle.
     From: Nicholas Jolley (Leibniz [2005], Ch.3)
     A reaction: Both principles are false, because they are the classic confusion of epistemology and ontology. The fact that you cannot 'discern' a difference between two things doesn't mean that there is no difference. Things beyond verification can still be discussed.