Combining Philosophers

All the ideas for Porphyry, Sextus Empiricus and New Scientist writers

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162 ideas

1. Philosophy / D. Nature of Philosophy / 5. Aims of Philosophy / b. Philosophy as transcendent
Philosophy has its own mode of death, by separating soul from body [Porphyry]
1. Philosophy / F. Analytic Philosophy / 2. Analysis by Division
You cannot divide anything into many parts, because after the first division you are no longer dividing the original [Sext.Empiricus]
1. Philosophy / F. Analytic Philosophy / 5. Linguistic Analysis
Ordinary speech is not exact about what is true; we say we are digging a well before the well exists [Sext.Empiricus]
2. Reason / A. Nature of Reason / 9. Limits of Reason
Reasoning is impossible without a preconception [Sext.Empiricus]
2. Reason / E. Argument / 6. Conclusive Proof
Proof moves from agreed premises to a non-evident inference [Sext.Empiricus]
3. Truth / A. Truth Problems / 5. Truth Bearers
It is only when we say a proposition that we speak truly or falsely [Sext.Empiricus]
5. Theory of Logic / B. Logical Consequence / 8. Material Implication
A valid hypothetical syllogism is 'that which does not begin with a truth and end with a falsehood' [Sext.Empiricus]
5. Theory of Logic / E. Structures of Logic / 1. Logical Form
'Man is a rational mortal animal' is equivalent to 'if something is a man, that thing is a rational mortal animal' [Sext.Empiricus]
5. Theory of Logic / L. Paradox / 7. Paradoxes of Time
Since Socrates either died when he was alive (a contradiction) or died when he was dead (meaningless), he didn't die [Sext.Empiricus]
7. Existence / A. Nature of Existence / 5. Reason for Existence
Current physics says matter and antimatter should have reduced to light at the big bang [New Sci.]
CP violation shows a decay imbalance in matter and antimatter, leading to matter's dominance [New Sci.]
8. Modes of Existence / C. Powers and Dispositions / 2. Powers as Basic
The presence of the incorporeal is only known by certain kinds of disposition [Porphyry]
8. Modes of Existence / D. Universals / 1. Universals
Are genera and species real or conceptual? bodies or incorporeal? in sensibles or separate from them? [Porphyry]
9. Objects / B. Unity of Objects / 1. Unifying an Object / a. Intrinsic unification
Diversity arises from the power of unity [Porphyry]
9. Objects / C. Structure of Objects / 8. Parts of Objects / c. Wholes from parts
Parts are not parts if their whole is nothing more than the parts [Sext.Empiricus]
9. Objects / D. Essence of Objects / 9. Essence and Properties
Some properties are inseparable from a thing, such as the length, breadth and depth of a body [Sext.Empiricus]
11. Knowledge Aims / B. Certain Knowledge / 2. Common Sense Certainty
If an argument has an absurd conclusion, we should not assent to the absurdity, but avoid the absurd argument [Sext.Empiricus]
11. Knowledge Aims / C. Knowing Reality / 1. Perceptual Realism / c. Representative realism
Whether honey is essentially sweet may be doubted, as it is a matter of judgement rather than appearance [Sext.Empiricus]
12. Knowledge Sources / B. Perception / 5. Interpretation
How can the intellect know if sensation is reliable if it doesn't directly see external objects? [Sext.Empiricus]
12. Knowledge Sources / C. Rationalism / 1. Rationalism
Some say motion is perceived by sense, but others say it is by intellect [Sext.Empiricus]
12. Knowledge Sources / D. Empiricism / 3. Pragmatism
We distinguish ambiguities by seeing what is useful [Sext.Empiricus]
12. Knowledge Sources / E. Direct Knowledge / 4. Memory
Memory is not conserved images, but reproduction of previous thought [Porphyry]
13. Knowledge Criteria / A. Justification Problems / 1. Justification / b. Need for justification
Fools, infants and madmen may speak truly, but do not know [Sext.Empiricus]
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / b. Basic beliefs
Some things are their own criterion, such as straightness, a set of scales, or light [Sext.Empiricus]
13. Knowledge Criteria / C. External Justification / 3. Reliabilism / a. Reliable knowledge
Madmen are reliable reporters of what appears to them [Sext.Empiricus]
13. Knowledge Criteria / D. Scepticism / 1. Scepticism
The basis of scepticism is the claim that every proposition has an equal opposing proposition [Sext.Empiricus]
13. Knowledge Criteria / D. Scepticism / 3. Illusion Scepticism
The necks of doves appear different in colour depending on the angle of viewing [Sext.Empiricus]
The same oar seems bent in water and straight when out of it [Sext.Empiricus]
The same tower appears round from a distance, but square close at hand [Sext.Empiricus]
If we press the side of an eyeball, objects appear a different shape [Sext.Empiricus]
13. Knowledge Criteria / D. Scepticism / 6. Scepticism Critique
How can sceptics show there is no criterion? Weak without, contradiction with [Sext.Empiricus]
13. Knowledge Criteria / E. Relativism / 1. Relativism
How can we judge between our impressions and those of other animals, when we ourselves are involved? [Sext.Empiricus]
13. Knowledge Criteria / E. Relativism / 3. Subjectivism
Water that seems lukewarm can seem very hot on inflamed skin [Sext.Empiricus]
Some actions seem shameful when sober but not when drunk [Sext.Empiricus]
If we had no hearing or sight, we would assume no sound or sight exists, so there may be unsensed qualities [Sext.Empiricus]
Sickness is perfectly natural to the sick, so their natural perceptions should carry some weight [Sext.Empiricus]
If we enjoy different things, presumably we receive different impressions [Sext.Empiricus]
13. Knowledge Criteria / E. Relativism / 4. Cultural relativism
With us it is shameful for men to wear earrings, but among Syrians it is considered noble [Sext.Empiricus]
Even if all known nations agree on a practice, there may be unknown nations which disagree [Sext.Empiricus]
14. Science / A. Basis of Science / 1. Observation
How can you investigate without some preconception of your object? [Sext.Empiricus]
14. Science / A. Basis of Science / 4. Prediction
A system can infer the structure of the world by making predictions about it [New Sci.]
14. Science / C. Induction / 3. Limits of Induction
If you don't view every particular, you may miss the one which disproves your universal induction [Sext.Empiricus]
15. Nature of Minds / A. Nature of Mind / 1. Mind / c. Features of mind
Intelligence is aware of itself, so the intelligence is both the thinker and the thought [Porphyry]
15. Nature of Minds / A. Nature of Mind / 1. Mind / d. Location of mind
The soul is everywhere and nowhere in the body, and must be its cause [Porphyry]
15. Nature of Minds / C. Capacities of Minds / 3. Abstraction by mind
Neural networks can extract the car-ness of a car, or the chair-ness of a chair [New Sci.]
15. Nature of Minds / C. Capacities of Minds / 6. Idealisation
If we try to conceive of a line with no breadth, it ceases to exist, and so has no length [Sext.Empiricus]
16. Persons / C. Self-Awareness / 2. Knowing the Self
Successful introspection reveals the substrate along with the object of thought [Porphyry]
17. Mind and Body / A. Mind-Body Dualism / 1. Dualism
The soul is bound to matter by the force of its own disposition [Porphyry]
17. Mind and Body / D. Property Dualism / 4. Emergentism
The incorporeal is not in the nature of body, and so could not emerge from it [Sext.Empiricus]
18. Thought / A. Modes of Thought / 5. Rationality / a. Rationality
No one has yet devised a rationality test [New Sci.]
18. Thought / A. Modes of Thought / 6. Judgement / a. Nature of Judgement
If we utter three steps of a logical argument, they never exist together [Sext.Empiricus]
18. Thought / A. Modes of Thought / 7. Intelligence
People can be highly intelligent, yet very stupid [New Sci.]
About a third of variation in human intelligence is environmental [New Sci.]
18. Thought / B. Mechanics of Thought / 1. Psychology
Psychologists measure personality along five dimensions [New Sci.]
18. Thought / D. Concepts / 2. Origin of Concepts / b. Empirical concepts
We can only dream of a winged man if we have experienced men and some winged thing [Sext.Empiricus]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / e. Human nature
Justice is each person fulfilling his function [Porphyry]
22. Metaethics / B. Value / 2. Values / g. Love
We should avoid the pleasures of love, or at least, should not enact our dreams [Porphyry]
22. Metaethics / C. The Good / 1. Goodness / a. Form of the Good
Saying the good is useful or choiceworth or happiness-creating is not the good, but a feature of it [Sext.Empiricus]
22. Metaethics / C. The Good / 1. Goodness / b. Types of good
Like a warming fire, what is good by nature should be good for everyone [Sext.Empiricus]
22. Metaethics / C. The Good / 2. Happiness / d. Routes to happiness
If a desire is itself desirable, then we shouldn't desire it, as achieving it destroys it [Sext.Empiricus]
23. Ethics / B. Contract Ethics / 9. Contractualism
Right actions, once done, are those with a reasonable justification [Sext.Empiricus]
23. Ethics / C. Virtue Theory / 2. Elements of Virtue Theory / c. Motivation for virtue
Civil virtues make us behave benevolently, and thereby unite citizens [Porphyry]
Civil virtues control the passions, and make us conform to our nature [Porphyry]
Purificatory virtues detach the soul completely from the passions [Porphyry]
23. Ethics / C. Virtue Theory / 3. Virtues / a. Virtues
There are practical, purificatory, contemplative, and exemplary virtues [Porphyry]
26. Natural Theory / A. Speculations on Nature / 1. Nature
Unified real existence is neither great nor small, though greatness and smallness participate in it [Porphyry]
26. Natural Theory / A. Speculations on Nature / 4. Mathematical Nature
The tektraktys (1+2+3+4=10) is the 'fount of ever-flowing nature' [Sext.Empiricus]
26. Natural Theory / C. Causation / 4. Naturalised causation
Some say that causes are physical, some say not [Sext.Empiricus]
26. Natural Theory / C. Causation / 7. Eliminating causation
Knowing an effect results from a cause means knowing that the cause belongs with the effect, which is circular [Sext.Empiricus]
Cause can't exist before effect, or exist at the same time, so it doesn't exist [Sext.Empiricus]
If there were no causes then everything would have been randomly produced by everything [Sext.Empiricus]
26. Natural Theory / C. Causation / 8. Particular Causation / c. Conditions of causation
Causes are either equal to the effect, or they link equally with other causes, or they contribute slightly [Sext.Empiricus]
27. Natural Reality / A. Classical Physics / 1. Mechanics / a. Explaining movement
If time and place are infinitely divided, it becomes impossible for movement ever to begin [Sext.Empiricus]
Does the original self-mover push itself from behind, or pull itself from in front? [Sext.Empiricus]
If all atoms, times and places are the same, everything should move with equal velocity [Sext.Empiricus]
A man walking backwards on a forwards-moving ship is moving in a fixed place [Sext.Empiricus]
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 / A. Classical Physics / 2. Thermodynamics / d. Entropy
Entropy is the only time-asymmetric law, so time may be linked to entropy [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.]
Light moves at a constant space-time speed, but its direction is in neither space nor time [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 / 2. Electrodynamics / d. Quantum mechanics
Quantum states are measured by external time, of unknown origin [New Sci.]
The Schrödinger equation describes the evolution of an object's wave function in Hilbert space [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.]
Gluons, the particles carrying the strong force, interact because of their colour charge [New Sci.]
The strong force binds quarks tight, and the nucleus more weakly [New Sci.]
27. Natural Reality / B. Modern Physics / 3. Chromodynamics / b. Quarks
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.]
Three different colours of quark (as in the proton) can cancel out to give no colour [New Sci.]
27. Natural Reality / B. Modern Physics / 4. Standard Model / b. Standard model
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.]
Three particles enable the weak force: W+ and W- are charged, and Z° is not [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
Spin is a built-in ration of angular momentum [New Sci.]
Quarks have red, green or blue colour charge (akin to electric charge) [New Sci.]
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.]
Particles are spread out, with wave-like properties, and higher energy shortens the wavelength [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
Neutrons are slightly heavier than protons, and decay into them by emitting an electron [New Sci.]
Top, bottom, charm and strange quarks quickly decay into up and down [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
It is impossible for find a model of actuality among the innumerable models in string theory [New Sci.]
String theory is now part of 11-dimensional M-Theory, involving p-branes [New Sci.]
In string theory space-time has a grainy indivisible substructure [New Sci.]
String theory needs at least 10 space-time dimensions [New Sci.]
Supersymmetric string theory can be expressed using loop quantum gravity [New Sci.]
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.]
27. Natural Reality / B. Modern Physics / 5. Unified Models / c. Supersymmetry
Only supersymmetry offers to incorporate gravity into the scheme [New Sci.]
Supersymmetry has extra heavy bosons and heavy fermions [New Sci.]
Supersymmetry says particles and superpartners were unities, but then split [New Sci.]
The evidence for supersymmetry keeps failing to appear [New Sci.]
27. Natural Reality / C. Space / 2. Space
Hilbert Space is an abstraction representing all possible states of a quantum system [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 / C. Space / 6. Space-Time
Einstein's merging of time with space has left us confused about the nature of time [New Sci.]
Relativity makes time and space jointly basic; quantum theory splits them, and prioritises time [New Sci.]
Space-time may be a geometrical manifestation of quantum entanglement [New Sci.]
27. Natural Reality / D. Time / 1. Nature of Time / b. Relative time
If motion and rest are abolished, so is time [Sext.Empiricus]
27. Natural Reality / D. Time / 1. Nature of Time / c. Idealist time
Time is the circular movement of the soul [Porphyry]
27. Natural Reality / D. Time / 1. Nature of Time / d. Time as measure
Quantum theory relies on a clock outside the system - but where is it located? [New Sci.]
27. Natural Reality / D. Time / 1. Nature of Time / e. Eventless time
Some think time is seen at rest, as well as in movement [Porphyry]
27. Natural Reality / D. Time / 1. Nature of Time / i. Denying time
Time must be unlimited, but past and present can't be non-existent, and can't be now, so time does not exist [Sext.Empiricus]
27. Natural Reality / D. Time / 2. Passage of Time / c. Tenses and time
Time doesn't end with the Universe, because tensed statements about destruction remain true [Sext.Empiricus]
27. Natural Reality / D. Time / 2. Passage of Time / g. Time's arrow
Entropy is puzzling, so we may need to build new laws which include time directionality [New Sci.]
27. Natural Reality / D. Time / 3. Parts of Time / c. Intervals
Time is divisible, into past, present and future [Sext.Empiricus]
How can time be divisible if we can't compare one length of time with another? [Sext.Empiricus]
27. Natural Reality / D. Time / 3. Parts of Time / e. Present moment
Socrates either dies when he exists (before his death) or when he doesn't (after his death) [Sext.Empiricus]
If the present is just the limit of the past or the future, it can't exist because they don't exist [Sext.Empiricus]
27. Natural Reality / E. Cosmology / 7. Black Holes
General relativity predicts black holes, as former massive stars, and as galaxy centres [New Sci.]
Black holes have entropy, but general relativity says they are unstructured, and lack entropy [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.]
84.5 percent of the universe is made of dark matter [New Sci.]
27. Natural Reality / F. Chemistry / 1. Chemistry
We are halfway to synthesising any molecule we want [New Sci.]
27. Natural Reality / F. Chemistry / 3. Periodic Table
Chemistry just needs the periodic table, and protons, electrons and neutrinos [New Sci.]
28. God / A. Divine Nature / 2. Divine Nature
God must suffer to understand suffering [Sext.Empiricus]
All men agree that God is blessed, imperishable, happy and good [Sext.Empiricus]
God is nowhere, and hence everywhere [Porphyry]
How can we agree on the concept of God, unless we agree on his substance or form or place? [Sext.Empiricus]
28. God / A. Divine Nature / 3. Divine Perfections
The Divine must lack the virtues of continence and fortitude, because they are not needed [Sext.Empiricus]
28. God / B. Proving God / 1. Proof of God
God is defended by agreement, order, absurdity of denying God, and refutations [Sext.Empiricus]
28. God / B. Proving God / 2. Proofs of Reason / b. Ontological Proof critique
God's sensations imply change, and hence perishing, which is absurd, so there is no such God [Sext.Empiricus]
God without virtue is absurd, but God's virtues will be better than God [Sext.Empiricus]
The existence of God can't be self-evident or everyone would have agreed on it, so it needs demonstration [Sext.Empiricus]
28. God / B. Proving God / 3. Proofs of Evidence / b. Teleological Proof
The original substance lacked motion or shape, and was given these by a cause [Sext.Empiricus]
28. God / C. Attitudes to God / 2. Pantheism
Everything existing proceeds from divinity, and is within divinity [Porphyry]
28. God / C. Attitudes to God / 4. God Reflects Humanity
The perfections of God were extrapolations from mankind [Sext.Empiricus]
28. God / C. Attitudes to God / 5. Atheism
Gods were invented as watchers of people's secret actions [Sext.Empiricus]
An incorporeal God could do nothing, and a bodily god would perish, so there is no God [Sext.Empiricus]
29. Religion / A. Polytheistic Religion / 1. Animism
It is mad to think that what is useful to us, like lakes and rivers, are gods [Sext.Empiricus]
29. Religion / D. Religious Issues / 2. Immortality / b. Soul
Nature binds or detaches body to soul, but soul itself joins and detaches soul from body [Porphyry]
Individual souls are all connected, though distinct, and without dividing universal Soul [Porphyry]
29. Religion / D. Religious Issues / 3. Problem of Evil / d. Natural Evil
If God foresaw evil he would presumably prevent it, and if he only foresees some things, why those things? [Sext.Empiricus]