Combining Texts

All the ideas for 'fragments/reports', 'Treatise on Quantity' and 'The Foundations of Mathematics (2nd ed)'

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3 ideas

8. Modes of Existence / A. Relations / 4. Formal Relations / b. Equivalence relation
An 'equivalence' relation is one which is reflexive, symmetric and transitive [Kunen]
     Full Idea: R is an equivalence relation on A iff R is reflexive, symmetric and transitive on A.
     From: Kenneth Kunen (The Foundations of Mathematics (2nd ed) [2012], I.7.1)
9. Objects / C. Structure of Objects / 4. Quantity of an Object
Quantity is the quantified parts of a thing, plus location and coordination [Olivi]
     Full Idea: Quantity refers to nothing other than the parts of the thing quantified, together with their location or position, being extrinsically coordinated with each other.
     From: Peter John Olivi (Treatise on Quantity [1286], f. 49vb), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 14.1
     A reaction: I'm not sure I understand 'extrinsically'. Is there some external stretching force? God spends his time spreading out his stuff? It is nice that being spread out isn't taken for granted. We take much more for granted than they did. Motion, for example.
13. Knowledge Criteria / E. Relativism / 2. Knowledge as Convention
By nature people are close to one another, but culture drives them apart [Hippias]
     Full Idea: I regard you all as relatives - by nature, not by convention. By nature like is akin to like, but convention is a tyrant over humankind and often constrains people to act contrary to nature.
     From: Hippias (fragments/reports [c.430 BCE]), quoted by Plato - Protagoras 337c8