Combining Texts

All the ideas for 'What is Logic?st1=Ian Hacking', 'works' and 'Truth-makers and dependence'

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

22 ideas

2. Reason / D. Definition / 3. Types of Definition
13838 A decent modern definition should always imply a semantics [Hacking]
3. Truth / B. Truthmakers / 2. Truthmaker Relation
17325 Truth-maker theory can't cope with non-causal dependence [Liggins]
3. Truth / B. Truthmakers / 12. Rejecting Truthmakers
17318 Truthmakers for existence is fine; otherwise maybe restrict it to synthetic truths? [Liggins]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / d. Basic theorems of PL
13834 Gentzen's Cut Rule (or transitivity of deduction) is 'If A |- B and B |- C, then A |- C' [Hacking]
13835 Only Cut reduces complexity, so logic is constructive without it, and it can be dispensed with [Hacking]
13833 'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [Hacking]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
13845 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
13840 First-order logic is the strongest complete compact theory with Löwenheim-Skolem [Hacking]
13844 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
13842 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
13837 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
13839 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
13843 If it is a logic, the Löwenheim-Skolem theorem holds for it [Hacking]
7. Existence / A. Nature of Existence / 5. Reason for Existence
17320 Either p is true or not-p is true, so something is true, so something exists [Liggins]
7. Existence / C. Structure of Existence / 1. Grounding / b. Relata of grounding
17326 The dependence of {Socrates} on Socrates involves a set and a philosopher, not facts [Liggins]
7. Existence / C. Structure of Existence / 4. Ontological Dependence
17327 Non-causal dependence is at present only dimly understood [Liggins]
7. Existence / C. Structure of Existence / 5. Supervenience / c. Significance of supervenience
17322 Necessities supervene on everything, but don't depend on everything [Liggins]
11. Knowledge Aims / A. Knowledge / 4. Belief / d. Cause of beliefs
20945 Belief is no more rational than is tasting and smelling [Hamann]
14. Science / D. Explanation / 1. Explanation / a. Explanation
17324 'Because' can signal an inference rather than an explanation [Liggins]
14. Science / D. Explanation / 2. Types of Explanation / a. Types of explanation
17321 Value, constitution and realisation are non-causal dependences that explain [Liggins]
17323 If explanations track dependence, then 'determinative' explanations seem to exist [Liggins]
28. God / A. Divine Nature / 2. Divine Nature
7666 God is not a mathematician, but a poet [Hamann, by Berlin]