Combining Texts

All the ideas for 'What is Logic?st1=Ian Hacking', 'Stipulation, Meaning and Apriority' and 'Philosophy'

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

29 ideas

2. Reason / D. Definition / 3. Types of Definition
13838 A decent modern definition should always imply a semantics [Hacking]
2. Reason / D. Definition / 13. Against Definition
9331 How do we determine which of the sentences containing a term comprise its definition? [Horwich]
3. Truth / A. Truth Problems / 4. Uses of Truth
20320 Truth is what unites, and the profound truths create a community [Jaspers]
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]
12. Knowledge Sources / A. A Priori Knowledge / 1. Nature of the A Priori
9333 A priori belief is not necessarily a priori justification, or a priori knowledge [Horwich]
12. Knowledge Sources / A. A Priori Knowledge / 6. A Priori from Reason
9342 Understanding needs a priori commitment [Horwich]
12. Knowledge Sources / A. A Priori Knowledge / 8. A Priori as Analytic
9332 Meaning is generated by a priori commitment to truth, not the other way around [Horwich]
12. Knowledge Sources / A. A Priori Knowledge / 9. A Priori from Concepts
9341 Meanings and concepts cannot give a priori knowledge, because they may be unacceptable [Horwich]
9334 If we stipulate the meaning of 'number' to make Hume's Principle true, we first need Hume's Principle [Horwich]
12. Knowledge Sources / A. A Priori Knowledge / 10. A Priori as Subjective
9339 A priori knowledge (e.g. classical logic) may derive from the innate structure of our minds [Horwich]
16. Persons / F. Free Will / 2. Sources of Free Will
20323 Freedom needs knowledge, the possibility of arbitrariness, and law [Jaspers]
16. Persons / F. Free Will / 4. For Free Will
20322 I am aware that freedom is possible, and the freedom is not in theory, but in seeking freedom [Jaspers]
20. Action / C. Motives for Action / 4. Responsibility for Actions
20324 My freedom increases as I broaden my vision of possiblities and motives [Jaspers]
23. Ethics / F. Existentialism / 1. Existentialism
20321 The struggle for Existenz is between people who are equals, and are utterly honest [Jaspers]
20318 My helplessness in philosophising reveals my being, and begins its upsurge [Jaspers]
20325 Once we grasp freedom 'from' things, then freedom 'for' things becomes urgent [Jaspers]
23. Ethics / F. Existentialism / 6. Authentic Self
20315 'Existenz' is the potential being, which I could have, and ought to have [Jaspers]
20317 Mundane existence is general, falling under universals, but Existens is unique to individuals [Jaspers]
20319 We want the correct grasp on being that is neither solipsism nor absorption in the crowd [Jaspers]
23. Ethics / F. Existentialism / 7. Existential Action
20316 Every decision I make moves towards or away from fulfilled Existenz [Jaspers]