31 ideas
| 16456 | For modality Lewis rejected boxes and diamonds, preferring worlds, and an index for the actual one [Lewis, by Stalnaker] |
| Full Idea: Lewis was suspicious of boxes and diamonds as regimenting ordinary modal thought, …preferring a first-order extensional theory including possible worlds in its domain and an indexical singular term for the actual world. | |
| From: report of David Lewis (Anselm and Actuality [1970]) by Robert C. Stalnaker - Mere Possibilities 3.8 |
| 7352 | Jesus said learning was unnecessary, and only the spirit of the Law was needed [Jesus, by Johnson,P] |
| Full Idea: Jesus was a learned Jew who said that learning was not necessary, who took the spirit and not the letter as the essence of the Law. | |
| From: report of Jesus (reports [c.32]) by Paul Johnson - The History of the Jews Pt II | |
| A reaction: This seems to me the perfect opposite of Socrates's intellectualism, offering the essence of morality as 'purity of heart', rather than careful thought about virtue or principles. On the whole I am with Socrates, but the idea is interesting. |
| 6289 | Love your enemies [Jesus] |
| Full Idea: Love your enemies. | |
| From: Jesus (reports [c.32]), quoted by St Matthew - 01: Gospel of St Matthew 05.44 | |
| A reaction: The germ of this idea had been around for several hundred years, but this very forceful statement is perhaps Jesus' most distinctive contribution to moral thought. It has the same clarion call as the Stoic demand for pure virtue. What about deserving? |
| 6292 | Love thy neighbour as thyself [Jesus] |
| Full Idea: Love thy neighbour as thyself. | |
| From: Jesus (reports [c.32]), quoted by St Matthew - 01: Gospel of St Matthew 19.19 | |
| A reaction: It would be stronger and better to say 'Love your neighbour, even if you don't love yourself'. Self-loathing and vicious hatred often go together. For once Jesus does not attach an instant heavenly reward to obedience of the command. |
| 5356 | Treat others as you would have them treat you [Jesus] |
| Full Idea: All things whatsoever ye would that men should do to you, so ye even so to them: for this is the law and the prophets. | |
| From: Jesus (reports [c.32]), quoted by St Matthew - 01: Gospel of St Matthew 07.12 | |
| A reaction: A problem which probably didn't occur to Jesus and the prophets is that of masochists. Personally I like buying philosophy books, but most people have no such desire. The Rule needs restricting to the basics of pleasure and pain. |
| 6286 | Blessed are the merciful: for they shall obtain mercy [Jesus] |
| Full Idea: Blessed are the merciful: for they shall obtain mercy. | |
| From: Jesus (reports [c.32]), quoted by St Matthew - 01: Gospel of St Matthew 05.07 | |
| A reaction: This appears to be a straightforward application of social contract morality, with God playing the role of Hobbes' absolute monarch. It highlights the uncomfortable fact at the heart of Christian morality, that the motivation for altruism is selfish. |
| 6290 | Except ye become as little children, ye shall not enter heaven [Jesus] |
| Full Idea: Except ye be converted, and become as little children, ye shall not enter into the kingdom of heaven. | |
| From: Jesus (reports [c.32]), quoted by St Matthew - 01: Gospel of St Matthew 18.03 | |
| A reaction: The appeal of such purity of heart is undeniable, but essentially I dislike this remark. It is the opponent of education, reason, autonomy, responsibility, democracy and maturity. It confirms the view that religion is the opium of the people. |
| 6287 | If you lust after a woman, you have committed adultery [Jesus] |
| Full Idea: Whosoever look on a woman to lust after her hath committed adultery with her already in his heart. | |
| From: Jesus (reports [c.32]), quoted by St Matthew - 01: Gospel of St Matthew 05.28 | |
| A reaction: Compare Democritus, Idea 503. Literally this idea seems absurd, but it is also at the heart of Greek virtue theory. Aristotle (Idea 34) defines virtue as an activity 'of the soul', not an action in the world. Excellence has become purity of soul. |
| 6285 | Blessed are the meek; for they shall inherit the earth [Jesus] |
| Full Idea: Blessed are the meek; for they shall inherit the earth. | |
| From: Jesus (reports [c.32]), quoted by St Matthew - 01: Gospel of St Matthew 05.05 | |
| A reaction: If they are truly meek, why would they want to inherit the earth? This is the classic statement of Nietzsche's 'inversion of values', where the qualities of a good slave are elevated above those of the greatest human beings. |
| 6288 | Don't resist evil, but turn the other cheek [Jesus] |
| Full Idea: Ye have heard it said, An eye for an eye, and a tooth for a tooth; But I say unto you, That ye resist not evil, but whosoever shall smite thee on thy right cheek, turn to him the other also. | |
| From: Jesus (reports [c.32]), quoted by St Matthew - 01: Gospel of St Matthew 05.38-9 | |
| A reaction: Compare Socrates, Idea 346. The viciousness of many Hollywood movies is that they set up a character as thoroughly evil so that we can have the pleasure of watching him pulverised. On the whole, Jesus gives bad advice. 'Doormats' in game theory. |
| 6293 | It is almost impossible for the rich to go to heaven [Jesus] |
| Full Idea: It is easier for a camel to go through the eye of a needle, than for a rich man to enter into the kingdom of God. | |
| From: Jesus (reports [c.32]), quoted by St Matthew - 01: Gospel of St Matthew 19.24 | |
| A reaction: Aristotle and others (Margaret Thatcher) have observed that you cannot practise charity if you are poor. Jesus implies that the human race should remain in poverty. No wonder autocratic medieval rulers taught Christianity to peasants. Cf. Matt 25.30. |
| 20624 | Work degrades into heat, but not vice versa [Close] |
| Full Idea: William Thomson, Lord Kelvin, declared (in 1865) the second law of thermodynamics: mechanical work inevitably tends to degrade into heat, but not vice versa. | |
| From: Frank Close (Theories of Everything [2017], 3 'Perpetual') | |
| A reaction: The basis of entropy, which makes time an essential part of physics. Might this be the single most important fact about the physical world? |
| 20623 | First Law: energy can change form, but is conserved overall [Close] |
| Full Idea: The first law of thermodynamics : energy can be changed from one form to another, but is always conserved overall. | |
| From: Frank Close (Theories of Everything [2017], 3 'Perpetual') | |
| A reaction: So we have no idea what energy is, but we know it's conserved. (Daniel Bernoulli showed the greater the mean energy, the higher the temperature. James Joule showed the quantitative equivalence of heat and work p.26-7) |
| 20625 | Third Law: total order and minimum entropy only occurs at absolute zero [Close] |
| Full Idea: The third law of thermodynamics says that a hypothetical state of total order and minimum entropy can be attained only at the absolute zero temperature, minus 273 degrees Celsius. | |
| From: Frank Close (Theories of Everything [2017], 3 'Arrow') | |
| A reaction: If temperature is energetic movement of atoms (or whatever), then obviously zero movement is the coldest it can get. So is absolute zero an energy state, or an absence of energy? I have no idea what 'total order' means. |
| 20622 | All motions are relative and ambiguous, but acceleration is the same in all inertial frames [Close] |
| Full Idea: There is no absolute state of rest; only relative motions are unambiguous. Contrast this with acceleration, however, which has the same magnitude in all inertial frames. | |
| From: Frank Close (Theories of Everything [2017], 3 'Newton's') | |
| A reaction: It seems important to remember this, before we start trumpeting about the whole of physics being relative. ....But see Idea 20634! |
| 20628 | The electric and magnetic are tightly linked, and viewed according to your own motion [Close] |
| Full Idea: Electric and magnetic phenomena are profoundly intertwined; what you interpret as electric or magnetic thus depends on your own motion. | |
| From: Frank Close (Theories of Everything [2017], 3 'Light!') | |
| A reaction: This sounds like an earlier version of special relativity. |
| 20635 | The general relativity equations relate curvature in space-time to density of energy-momentum [Close] |
| Full Idea: The essence of general relativity relates 'curvature in space-time' on one side of the equation to the 'density of momentum and energy' on the other. ...In full, Einstein required ten equations of this type. | |
| From: Frank Close (Theories of Everything [2017], 5 'Gravity') | |
| A reaction: Momentum involves mass, and energy is equivalent to mass (e=mc^2). |
| 20642 | Photon exchange drives the electro-magnetic force [Close] |
| Full Idea: The exchange of photons drives the electro-magnetic force. | |
| From: Frank Close (Theories of Everything [2017], 6 'Superstrings') | |
| A reaction: So light, which we just think of as what is visible, is a mere side-effect of the engine room of nature - the core mechanism of the whole electro-magnetic field. |
| 20627 | Electric fields have four basic laws (two by Gauss, one by Ampère, one by Faraday) [Close] |
| Full Idea: Four basic laws of electric and magnetic fields: Gauss's Law (about the flux produced by a field), Gauss's law of magnets (there can be no monopoles), Ampère's Law (fields on surfaces), and Farday's Law (accelerated magnets produce fields). | |
| From: Frank Close (Theories of Everything [2017], 3 'Light!') | |
| A reaction: [Highly compressed, for an overview. Close explains them] |
| 20630 | Light isn't just emitted in quanta called photons - light is photons [Close] |
| Full Idea: Planck had assumed that light is emitted in quanta called photons. Einstein went further - light is photons. | |
| From: Frank Close (Theories of Everything [2017], 3 'Light!') | |
| A reaction: The point is that light travels as entities which are photons, rather than the emissions being quantized packets of some other stuff. |
| 20637 | In general relativity the energy and momentum of photons subjects them to gravity [Close] |
| Full Idea: In Einstein's general theory, gravity acts also on energy and momentum, not simply on mass. For example, massless photons of light feel the gravitational attraction of the Sun and can be deflected. | |
| From: Frank Close (Theories of Everything [2017], 5 'Planck') | |
| A reaction: Ah, a puzzle solved. How come massless photons are bent by gravity? |
| 20629 | Electro-magnetic waves travel at light speed - so light is electromagnetism! [Close] |
| Full Idea: Faradays' measurements predicted the speed of electro-magnetic waves, which happened to be the speed of light, so Maxwell made an inspired leap: light is an electromagnetic wave! | |
| From: Frank Close (Theories of Everything [2017], 3 'Light!') | |
| A reaction: Put that way, it doesn't sound like an 'inspired' leap, because travelling at exactly the same speed seems a pretty good indication that they are the same sort of thing. (But I'm not denying that Maxwell was a special guy!) |
| 20632 | In QED, electro-magnetism exists in quantum states, emitting and absorbing electrons [Close] |
| Full Idea: Dirac created quantum electrodynamics (QED): the universal electro-magnetic field can exist in discreet states of energy (with photons appearing and disappearing by energy excitations. This combined classical ideas, quantum theory and special relativity. | |
| From: Frank Close (Theories of Everything [2017], 3 'Light!') | |
| A reaction: Close says this is the theory of everything in atomic structure, but not in nuclei (which needs QCD and QFD). So if there are lots of other 'fields' (e.g. gravitational, weak, strong, Higgs), how do they all fit together? Do they talk to one another? |
| 20639 | Quantum fields contain continual rapid creation and disappearance [Close] |
| Full Idea: Quantum field theory implies that the vacuum of space is filled with particles and antiparticles which bubble in and out of existence on faster and faster timescales over shorter and shorter distances. | |
| From: Frank Close (Theories of Everything [2017], 6 'Intro') | |
| A reaction: Ponder this sentence until you head aches. Existence, but not as we know it, Jim. Close says calculations in QED about the electron confirm this. |
| 20641 | Electrons get their mass by interaction with the Higgs field [Close] |
| Full Idea: The electron gets its mass by interaction with the ubiquitous Higgs field. | |
| From: Frank Close (Theories of Everything [2017], 6 'Hierarchy') | |
| A reaction: I thought I understood mass until I read this. Is it just wrong to say the mass of a table is the 'amount of stuff' in it? |
| 20631 | Dirac showed how electrons conform to special relativity [Close] |
| Full Idea: In 1928 Paul Dirac discovered the quantum equation that describes the electron and conforms to the requirements special relativity theory. | |
| From: Frank Close (Theories of Everything [2017], 3 'Light!') | |
| A reaction: This sounds like a major step in the unification of physics. Quantum theory and General relativity remain irreconcilable. |
| 20626 | Modern theories of matter are grounded in heat, work and energy [Close] |
| Full Idea: The link between temperature, heat, work and energy is at the root of our historical ability to construct theories of matter, such as Newton's dynamics, while ignoring, and indeed being ignorant of - atomic dimensions. | |
| From: Frank Close (Theories of Everything [2017], 3 'Arrow') | |
| A reaction: That is, presumably, that even when you fill in the atoms, and the standard model of physics, these aspects of matter do the main explaiining (of the behaviour, rather than of the structure). |
| 20633 | The Higgs field is an electroweak plasma - but we don't know what stuff it consists of [Close] |
| Full Idea: In 2012 it was confirmed that we are immersed in an electroweak plasma - the Higgs field. We curently have no knowledge of what this stuff might consist of. | |
| From: Frank Close (Theories of Everything [2017], 4 'Higgs') | |
| A reaction: The second sentence has my full attention. So we don't understand a field properly until we understand the 'stuff' it is made of? So what are all the familiar fields made of? Tell me more! |
| 20640 | Space-time is indeterminate foam over short distances [Close] |
| Full Idea: At very short distances, space-time itself becomes some indeterminate foam. | |
| From: Frank Close (Theories of Everything [2017], 6 'Intro') | |
| A reaction: [see Close for a bit more detail of this weird idea] |
| 6291 | No one is good except God [Jesus] |
| Full Idea: Why callest thou me good? There is none good but one, that is, God. | |
| From: Jesus (reports [c.32]), quoted by St Matthew - 01: Gospel of St Matthew 19.17 | |
| A reaction: This remark raises the problem that if God is good, there must be some separate moral standard by which he can be judged good. What is that standard? It is related to the problem of whether Plato's Form of the Beautiful is itself beautiful. |
| 7351 | Jesus turned the ideas of Hillel into a theology reduced to its moral elements [Jesus, by Johnson,P] |
| Full Idea: Jesus was a member of the school of Hillel the Elder, and may have sat under him. He repeated some of the sayings of Hillel, ...and turned his ideas into a moral theology, stripping the law of all but its moral and ethical elements. | |
| From: report of Jesus (reports [c.32]) by Paul Johnson - The History of the Jews Pt II | |
| A reaction: The crucial move, it seems to me, is to strip Judaism of its complexity, and reduce it to very simple moral maxims, which means that ordinary illiterate people no longer need priests to understand and follow it. Jesus was, above all, a great teacher. |