Combining Texts

All the ideas for 'Euthyphro', 'Outline of a System of the Philosophy of Nature' and 'What is Logic?'

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18 ideas

2. Reason / D. Definition / 3. Types of Definition
A decent modern definition should always imply a semantics [Hacking]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / d. Basic theorems of PL
'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [Hacking]
Gentzen's Cut Rule (or transitivity of deduction) is 'If A |- B and B |- C, then A |- C' [Hacking]
Only Cut reduces complexity, so logic is constructive without it, and it can be dispensed with [Hacking]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
The various logics are abstractions made from terms like 'if...then' in English [Hacking]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
First-order logic is the strongest complete compact theory with Löwenheim-Skolem [Hacking]
A limitation of first-order logic is that it cannot handle branching quantifiers [Hacking]
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Second-order completeness seems to need intensional entities and possible worlds [Hacking]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
With a pure notion of truth and consequence, the meanings of connectives are fixed syntactically [Hacking]
5. Theory of Logic / E. Structures of Logic / 4. Variables in Logic
Perhaps variables could be dispensed with, by arrows joining places in the scope of quantifiers [Hacking]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
If it is a logic, the Löwenheim-Skolem theorem holds for it [Hacking]
11. Knowledge Aims / C. Knowing Reality / 3. Idealism / d. Absolute idealism
For Schelling the Absolute spirit manifests as nature in which self-consciousness evolves [Schelling, by Lewis,PB]
Metaphysics aims at the Absolute, which goes beyond subjective and objective viewpoints [Schelling, by Pinkard]
13. Knowledge Criteria / E. Relativism / 6. Relativism Critique
Do the gods also hold different opinions about what is right and honourable? [Plato]
26. Natural Theory / A. Speculations on Nature / 1. Nature
Schelling sought a union between the productivities of nature and of the mind [Schelling, by Bowie]
Schelling made organisms central to nature, because mere mechanism could never produce them [Schelling, by Pinkard]
28. God / A. Divine Nature / 6. Divine Morality / b. Euthyphro question
Is what is pious loved by the gods because it is pious, or is it pious because they love it? (the 'Euthyphro Question') [Plato]
It seems that the gods love things because they are pious, rather than making them pious by loving them [Plato]