Combining Texts

All the ideas for 'What is Logic?st1=Ian Hacking', 'The Bhagavad Gita' and 'Principia Mathematica'

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


64 ideas

1. Philosophy / A. Wisdom / 1. Nature of Wisdom
Serene wisdom is freedom from ties, and indifference to fortune [Anon (Bhag)]
1. Philosophy / D. Nature of Philosophy / 1. Philosophy
Philosophy must abstract from the senses [Newton]
2. Reason / A. Nature of Reason / 7. Status of Reason
Seek salvation in the wisdom of reason [Anon (Bhag)]
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]
6. Mathematics / A. Nature of Mathematics / 2. Geometry
Newton developed a kinematic approach to geometry [Newton, by Kitcher]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / l. Limits
Quantities and ratios which continually converge will eventually become equal [Newton]
8. Modes of Existence / C. Powers and Dispositions / 2. Powers as Basic
I suspect that each particle of bodies has attractive or repelling forces [Newton]
8. Modes of Existence / D. Universals / 6. Platonic Forms / a. Platonic Forms
I am all the beauty and goodness of things, says Krishna [Anon (Bhag)]
9. Objects / B. Unity of Objects / 1. Unifying an Object / b. Unifying aggregates
Particles mutually attract, and cohere at short distances [Newton]
9. Objects / C. Structure of Objects / 8. Parts of Objects / b. Sums of parts
The place of a thing is the sum of the places of its parts [Newton]
14. Science / B. Scientific Theories / 6. Theory Holism
If you changed one of Newton's concepts you would destroy his whole system [Heisenberg on Newton]
14. Science / C. Induction / 1. Induction
Science deduces propositions from phenomena, and generalises them by induction [Newton]
14. Science / D. Explanation / 2. Types of Explanation / g. Causal explanations
We should admit only enough causes to explain a phenomenon, and no more [Newton]
Natural effects of the same kind should be assumed to have the same causes [Newton]
14. Science / D. Explanation / 2. Types of Explanation / k. Explanations by essence
From the phenomena, I can't deduce the reason for the properties of gravity [Newton]
15. Nature of Minds / B. Features of Minds / 1. Consciousness / a. Consciousness
In all living beings I am the light of consciousness, says Krishna [Anon (Bhag)]
20. Action / A. Definition of Action / 1. Action Theory
All actions come from: body, lower self, perception, means of action, or Fate [Anon (Bhag)]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / e. Human nature
Hate and lust have their roots in man's lower nature [Anon (Bhag)]
25. Social Practice / E. Policies / 1. War / a. Just wars
There is no greater good for a warrior than to fight in a just war [Anon (Bhag)]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / c. Ultimate substances
Newton's four fundamentals are: space, time, matter and force [Newton, by Russell]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / f. Ancient elements
The visible forms of nature are earth, water, fire, air, ether; mind, reason, and the sense of 'I' [Anon (Bhag)]
26. Natural Theory / A. Speculations on Nature / 7. Later Matter Theories / a. Early Modern matter
Mass is central to matter [Newton, by Hart,WD]
26. Natural Theory / A. Speculations on Nature / 7. Later Matter Theories / b. Corpuscles
An attraction of a body is the sum of the forces of their particles [Newton]
26. Natural Theory / C. Causation / 1. Causation
Newtonian causation is changes of motion resulting from collisions [Newton, by Baron/Miller]
26. Natural Theory / D. Laws of Nature / 6. Laws as Numerical
You have discovered that elliptical orbits result just from gravitation and planetary movement [Newton, by Leibniz]
We have given up substantial forms, and now aim for mathematical laws [Newton]
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / c. Essence and laws
I am not saying gravity is essential to bodies [Newton]
27. Natural Reality / A. Classical Physics / 1. Mechanics / a. Explaining movement
Newton reclassified vertical motion as violent, and unconstrained horizontal motion as natural [Newton, by Harré]
27. Natural Reality / A. Classical Physics / 1. Mechanics / b. Laws of motion
Inertia rejects the Aristotelian idea of things having natural states, to which they return [Newton, by Alexander,P]
1: Bodies rest, or move in straight lines, unless acted on by forces [Newton]
2: Change of motion is proportional to the force [Newton]
Newton's Third Law implies the conservation of momentum [Newton, by Papineau]
3: All actions of bodies have an equal and opposite reaction [Newton]
27. Natural Reality / A. Classical Physics / 1. Mechanics / c. Forces
Newton's idea of force acting over a long distance was very strange [Heisenberg on Newton]
Newton introduced forces other than by contact [Newton, by Papineau]
Newton's laws cover the effects of forces, but not their causes [Newton, by Papineau]
Newton's forces were accused of being the scholastics' real qualities [Pasnau on Newton]
I am studying the quantities and mathematics of forces, not their species or qualities [Newton]
The aim is to discover forces from motions, and use forces to demonstrate other phenomena [Newton]
27. Natural Reality / A. Classical Physics / 1. Mechanics / d. Gravity
Newton showed that falling to earth and orbiting the sun are essentially the same [Newton, by Ellis]
27. Natural Reality / A. Classical Physics / 2. Thermodynamics / c. Conservation of energy
Early Newtonians could not formulate conservation of energy, having no concept of potential energy [Newton, by Papineau]
27. Natural Reality / C. Space / 4. Substantival Space
Absolute space is independent, homogeneous and immovable [Newton]
27. Natural Reality / D. Time / 1. Nature of Time / a. Absolute time
Newton needs intervals of time, to define velocity and acceleration [Newton, by Le Poidevin]
Newton thought his laws of motion needed absolute time [Newton, by Bardon]
Time exists independently, and flows uniformly [Newton]
Absolute time, from its own nature, flows equably, without relation to anything external [Newton]
27. Natural Reality / D. Time / 2. Passage of Time / g. Time's arrow
Newtonian mechanics does not distinguish negative from positive values of time [Newton, by Coveney/Highfield]
27. Natural Reality / D. Time / 3. Parts of Time / d. Measuring time
If there is no uniform motion, we cannot exactly measure time [Newton]
28. God / A. Divine Nature / 1. God
Everything, including the gods, comes from me, says Krishna [Anon (Bhag)]
28. God / A. Divine Nature / 3. Divine Perfections
If a perfect being does not rule the cosmos, it is not God [Newton]
28. God / B. Proving God / 3. Proofs of Evidence / b. Teleological Proof
The elegance of the solar system requires a powerful intellect as designer [Newton]
29. Religion / A. Polytheistic Religion / 3. Hinduism
Brahman is supreme, Atman his spirit in man, and Karma is the force of creation [Anon (Bhag)]
29. Religion / D. Religious Issues / 1. Religious Commitment / e. Fideism
Only by love can men see me, know me, and come to me, says Krishna [Anon (Bhag)]
29. Religion / D. Religious Issues / 2. Immortality / e. Hell
The three gates of hell are lust, anger and greed [Anon (Bhag)]