Combining Texts

All the ideas for 'fragments/reports', 'Elucidation of some points in E.Schrder' and 'On the General Idea of Proof Theory'

expand these ideas     |    start again     |     specify just one area for these texts

---

5 ideas

4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set

14238

A class is an aggregate of objects; if you destroy them, you destroy the class; there is no empty class [Frege]

5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence

13827

Logical consequence isn't a black box (Tarski's approach); we should explain how arguments work [Prawitz]

5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models

13826

Model theory looks at valid sentences and consequence, but not how we know these things [Prawitz]

25. Social Practice / E. Policies / 5. Education / b. Education principles

13304

Learned men gain more in one day than others do in a lifetime [Posidonius]

27. Natural Reality / D. Time / 1. Nature of Time / d. Time as measure

20820

Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus]