Combining Texts

All the ideas for 'fragments/reports', 'Set Theory and related topics (2nd ed)' and 'Nonexistent Objects'

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4 ideas

4. Formal Logic / F. Set Theory ST / 3. Types of Set / e. Equivalence classes
Equivalence relations are reflexive, symmetric and transitive, and classify similar objects [Lipschutz]
9. Objects / A. Existence of Objects / 4. Impossible objects
There is an object for every set of properties (some of which exist, and others don't) [Parsons,T, by Sawyer]
26. Natural Theory / A. Speculations on Nature / 5. Infinite in Nature
Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius]
27. Natural Reality / G. Biology / 3. Evolution
Archelaus said life began in a primeval slime [Archelaus, by Schofield]