Combining Texts

All the ideas for 'Mahaprajnaparamitashastra', 'Parts of Classes' and 'Why the Universe Exists'

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77 ideas

4. Formal Logic / F. Set Theory ST / 1. Set Theory
Sets are mereological sums of the singletons of their members [Lewis, by Armstrong]
We can build set theory on singletons: classes are then fusions of subclasses, membership is the singleton [Lewis]
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / b. Terminology of ST
Classes divide into subclasses in many ways, but into members in only one way [Lewis]
A subclass of a subclass is itself a subclass; a member of a member is not in general a member [Lewis]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
We needn't accept this speck of nothingness, this black hole in the fabric of Reality! [Lewis]
We can accept the null set, but there is no null class of anything [Lewis]
There are four main reasons for asserting that there is an empty set [Lewis]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / c. Unit (Singleton) Sets
We can replace the membership relation with the member-singleton relation (plus mereology) [Lewis]
If we don't understand the singleton, then we don't understand classes [Lewis]
If singleton membership is external, why is an object a member of one rather than another? [Lewis]
Maybe singletons have a structure, of a thing and a lasso? [Lewis]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
Set theory has some unofficial axioms, generalisations about how to understand it [Lewis]
Set theory reduces to a mereological theory with singletons as the only atoms [Lewis, by MacBride]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / a. Sets as existing
Set theory isn't innocent; it generates infinities from a single thing; but mathematics needs it [Lewis]
If singletons are where their members are, then so are all sets [Lewis]
A huge part of Reality is only accepted as existing if you have accepted set theory [Lewis]
5. Theory of Logic / G. Quantification / 6. Plural Quantification
Plural quantification lacks a complete axiom system [Lewis]
I like plural quantification, but am not convinced of its connection with second-order logic [Lewis]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / f. Zermelo numbers
Zermelo's model of arithmetic is distinctive because it rests on a primitive of set theory [Lewis]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Giving up classes means giving up successful mathematics because of dubious philosophy [Lewis]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / a. Structuralism
To be a structuralist, you quantify over relations [Lewis]
7. Existence / A. Nature of Existence / 2. Types of Existence
Existence doesn't come in degrees; once asserted, it can't then be qualified [Lewis]
7. Existence / C. Structure of Existence / 8. Stuff / a. Pure stuff
We have no idea of a third sort of thing, that isn't an individual, a class, or their mixture [Lewis]
Atomless gunk is an individual whose parts all have further proper parts [Lewis]
8. Modes of Existence / B. Properties / 11. Properties as Sets
A property is any class of possibilia [Lewis]
9. Objects / C. Structure of Objects / 5. Composition of an Object
The many are many and the one is one, so they can't be identical [Lewis]
Lewis affirms 'composition as identity' - that an object is no more than its parts [Lewis, by Merricks]
9. Objects / C. Structure of Objects / 8. Parts of Objects / b. Sums of parts
In mereology no two things consist of the same atoms [Lewis]
Trout-turkeys exist, despite lacking cohesion, natural joints and united causal power [Lewis]
Given cats, a fusion of cats adds nothing further to reality [Lewis]
The one has different truths from the many; it is one rather than many, one rather than six [Lewis]
9. Objects / C. Structure of Objects / 8. Parts of Objects / c. Wholes from parts
Lewis prefers giving up singletons to giving up sums [Lewis, by Fine,K]
Lewis only uses fusions to create unities, but fusions notoriously flatten our distinctions [Oliver/Smiley on Lewis]
A commitment to cat-fusions is not a further commitment; it is them and they are it [Lewis]
12. Knowledge Sources / B. Perception / 2. Qualities in Perception / a. Qualities in perception
Some say qualities are parts of things - as repeatable universals, or as particulars [Lewis]
23. Ethics / C. Virtue Theory / 3. Virtues / a. Virtues
The six perfections are giving, morality, patience, vigour, meditation, and wisdom [Nagarjuna]
27. Natural Reality / A. Classical Physics / 1. Mechanics / d. Gravity
Gravity is unusual, in that it always attracts and never repels [New Sci.]
27. Natural Reality / B. Modern Physics / 1. Relativity / b. General relativity
In the Big Bang general relativity fails, because gravity is too powerful [New Sci.]
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / a. Electrodynamics
Quantum electrodynamics incorporates special relativity and quantum mechanics [New Sci.]
Photons have zero rest mass, so virtual photons have infinite range [New Sci.]
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / b. Fields
In the standard model all the fundamental force fields merge at extremely high energies [New Sci.]
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / c. Electrons
Electrons move fast, so are subject to special relativity [New Sci.]
27. Natural Reality / B. Modern Physics / 3. Chromodynamics / a. Chromodynamics
The strong force is repulsive at short distances, strong at medium, and fades at long [New Sci.]
The strong force binds quarks tight, and the nucleus more weakly [New Sci.]
Gluons, the particles carrying the strong force, interact because of their colour charge [New Sci.]
27. Natural Reality / B. Modern Physics / 3. Chromodynamics / b. Quarks
Three different colours of quark (as in the proton) can cancel out to give no colour [New Sci.]
Quarks in threes can build hadrons with spin ½ or with spin 3/2 [New Sci.]
Classifying hadrons revealed two symmetry patterns, produced by three basic elements [New Sci.]
27. Natural Reality / B. Modern Physics / 4. Standard Model / b. Standard model
Three particles enable the weak force: W+ and W- are charged, and Z° is not [New Sci.]
The four fundamental forces (gravity, electromagnetism, weak and strong) are the effects of particles [New Sci.]
The weak force explains beta decay, and the change of type by quarks and leptons [New Sci.]
The weak force particles are heavy, so the force has a short range [New Sci.]
Why do the charges of the very different proton and electron perfectly match up? [New Sci.]
The Standard Model cannot explain dark energy, survival of matter, gravity, or force strength [New Sci.]
27. Natural Reality / B. Modern Physics / 4. Standard Model / c. Particle properties
Fermions, with spin ½, are antisocial, and cannot share quantum states [New Sci.]
Spin is akin to rotation, and is easily measured in a magnetic field [New Sci.]
Spin is a built-in ration of angular momentum [New Sci.]
Particles are spread out, with wave-like properties, and higher energy shortens the wavelength [New Sci.]
Quarks have red, green or blue colour charge (akin to electric charge) [New Sci.]
27. Natural Reality / B. Modern Physics / 4. Standard Model / d. Mass
The mass of protons and neutrinos is mostly binding energy, not the quarks [New Sci.]
Gravitional mass turns out to be the same as inertial mass [New Sci.]
27. Natural Reality / B. Modern Physics / 4. Standard Model / e. Protons
Top, bottom, charm and strange quarks quickly decay into up and down [New Sci.]
Neutrons are slightly heavier than protons, and decay into them by emitting an electron [New Sci.]
27. Natural Reality / B. Modern Physics / 4. Standard Model / f. Neutrinos
Neutrinos were proposed as the missing energy in neutron beta decay [New Sci.]
Only neutrinos spin anticlockwise [New Sci.]
27. Natural Reality / B. Modern Physics / 4. Standard Model / g. Anti-matter
Standard antineutrinos have opposite spin and opposite lepton number [New Sci.]
27. Natural Reality / B. Modern Physics / 5. Unified Models / a. Electro-weak unity
The symmetry of unified electromagnetic and weak forces was broken by the Higgs field [New Sci.]
27. Natural Reality / B. Modern Physics / 5. Unified Models / b. String theory
String theory might be tested by colliding strings to make bigger 'stringballs' [New Sci.]
String theory offers a quantum theory of gravity, by describing the graviton [New Sci.]
String theory is now part of 11-dimensional M-Theory, involving p-branes [New Sci.]
Supersymmetric string theory can be expressed using loop quantum gravity [New Sci.]
27. Natural Reality / B. Modern Physics / 5. Unified Models / c. Supersymmetry
Supersymmetry has extra heavy bosons and heavy fermions [New Sci.]
Only supersymmetry offers to incorporate gravity into the scheme [New Sci.]
The evidence for supersymmetry keeps failing to appear [New Sci.]
Supersymmetry says particles and superpartners were unities, but then split [New Sci.]
27. Natural Reality / C. Space / 4. Substantival Space
The Higgs field means even low energy space is not empty [New Sci.]
27. Natural Reality / E. Cosmology / 8. Dark Matter
Dark matter must have mass, to produce gravity, and no electric charge, to not reflect light [New Sci.]