Huygens Quotes

Reading list (1972 edition)[edit] 1. Homer – Iliad, Odyssey 2. The Old Testament 3. Aeschylus – Tragedies 4. Sophocles – Tragedies 5. Herodotus – Histories 6. Euripides – Tragedies 7. Thucydides – History of the Peloponnesian War 8. Hippocrates – Medical Writings 9. Aristophanes – Comedies 10. Plato – Dialogues 11. Aristotle – Works 12. Epicurus – Letter to Herodotus; Letter to Menoecus 13. Euclid – Elements 14. Archimedes – Works 15. Apollonius of Perga – Conic Sections 16. Cicero – Works 17. Lucretius – On the Nature of Things 18. Virgil – Works 19. Horace – Works 20. Livy – History of Rome 21. Ovid – Works 22. Plutarch – Parallel Lives; Moralia 23. Tacitus – Histories; Annals; Agricola Germania 24. Nicomachus of Gerasa – Introduction to Arithmetic 25. Epictetus – Discourses; Encheiridion 26. Ptolemy – Almagest 27. Lucian – Works 28. Marcus Aurelius – Meditations 29. Galen – On the Natural Faculties 30. The New Testament 31. Plotinus – The Enneads 32. St. Augustine – On the Teacher; Confessions; City of God; On Christian Doctrine 33. The Song of Roland 34. The Nibelungenlied 35. The Saga of Burnt Njál 36. St. Thomas Aquinas – Summa Theologica 37. Dante Alighieri – The Divine Comedy;The New Life; On Monarchy 38. Geoffrey Chaucer – Troilus and Criseyde; The Canterbury Tales 39. Leonardo da Vinci – Notebooks 40. Niccolò Machiavelli – The Prince; Discourses on the First Ten Books of Livy 41. Desiderius Erasmus – The Praise of Folly 42. Nicolaus Copernicus – On the Revolutions of the Heavenly Spheres 43. Thomas More – Utopia 44. Martin Luther – Table Talk; Three Treatises 45. François Rabelais – Gargantua and Pantagruel 46. John Calvin – Institutes of the Christian Religion 47. Michel de Montaigne – Essays 48. William Gilbert – On the Loadstone and Magnetic Bodies 49. Miguel de Cervantes – Don Quixote 50. Edmund Spenser – Prothalamion; The Faerie Queene 51. Francis Bacon – Essays; Advancement of Learning; Novum Organum, New Atlantis 52. William Shakespeare – Poetry and Plays 53. Galileo Galilei – Starry Messenger; Dialogues Concerning Two New Sciences 54. Johannes Kepler – Epitome of Copernican Astronomy; Concerning the Harmonies of the World 55. William Harvey – On the Motion of the Heart and Blood in Animals; On the Circulation of the Blood; On the Generation of Animals 56. Thomas Hobbes – Leviathan 57. René Descartes – Rules for the Direction of the Mind; Discourse on the Method; Geometry; Meditations on First Philosophy 58. John Milton – Works 59. Molière – Comedies 60. Blaise Pascal – The Provincial Letters; Pensees; Scientific Treatises 61. Christiaan Huygens – Treatise on Light 62. Benedict de Spinoza – Ethics 63. John Locke – Letter Concerning Toleration; Of Civil Government; Essay Concerning Human Understanding;Thoughts Concerning Education 64. Jean Baptiste Racine – Tragedies 65. Isaac Newton – Mathematical Principles of Natural Philosophy; Optics 66. Gottfried Wilhelm Leibniz – Discourse on Metaphysics; New Essays Concerning Human Understanding;Monadology 67. Daniel Defoe – Robinson Crusoe 68. Jonathan Swift – A Tale of a Tub; Journal to Stella; Gulliver's Travels; A Modest Proposal 69. William Congreve – The Way of the World 70. George Berkeley – Principles of Human Knowledge 71. Alexander Pope – Essay on Criticism; Rape of the Lock; Essay on Man 72. Charles de Secondat, baron de Montesquieu – Persian Letters; Spirit of Laws 73. Voltaire – Letters on the English; Candide; Philosophical Dictionary 74. Henry Fielding – Joseph Andrews; Tom Jones 75. Samuel Johnson – The Vanity of Human Wishes; Dictionary; Rasselas; The Lives of the Poets

The world is my country, science is my religion.

I believe that we do not know anything for certain, but everything probably.

horas volat (time flies)

How vast those Orbs must be, and how inconsiderable this Earth, the Theatre upon which all our mighty Designs, all our Navigations, and all our Wars are transacted, is when compared to them. A very fit consideration, and matter of Reflection, for those Kings and Princes who sacrifice the Lives of so many People, only to flatter their Ambition in being Masters of some pitiful corner of this small Spot.

Huygens was, of course, a citizen of his time. Who of us is not? He claimed science as his religion and then argued that the planets must be inhabited because otherwise God had made worlds for nothing.

I esteem his understanding and subtlety highly, but I consider that they have been put to ill use in the greater part of his work, where the author studies things of little use... {Writing about Isaac Newton}

Jack fulfilled every inch of every requirement expected of him. Taking the lead when August got weak, handing it back when his own knees buckled. Hitting against each other back and forth until Newton's cradle turned into Huygens's pendulum and they finally moved as one. After that thought, all at once, like a horrible cacophony of sound, the voice that lived behind his teeth whispered: This is the love of your life.

Christiaan Huygens became simultaneously adept in languages, drawing, law, science, engineering, mathematics and music. His interests and allegiances were broad. “The world is my country,” he said, “science my religion.

In experimental philosophy we are to look upon propositions inferred by general induction from phenomena as accurately or very nearly true, notwithstanding any contrary hypotheses that may be imagined, till such time as other phenomena occur, by which they may either be made more accurate, or liable to exceptions. This rule we must follow, that the argument of induction may not be evaded by hypotheses.

What a wonderful and amazing Scheme have we here of the magnificent Vastness of the Universe! So many Suns, so many Earths, and every one of them stock’d with so many Herbs, Trees and Animals, and adorn’d with so many Seas and Mountains! And how must our wonder and admiration be encreased when we consider the prodigious distance and multitude of the Stars?

The taste of music with the inhabitants of Venus and Jupiter is at a high level, similar to that of Frenchmen or Italians.

We may mount from this dull Earth; and viewing it from on high, consider whether Nature has laid out all her cost and finery upon this small speck of Dirt. So, like Travellers into other distant countries, we shall be better able to judge of what’s done at home, know how to make a true estimate of, and set its own value upon every thing. We shall be less apt to admire what this World calls great, shall nobly despise those Trifles the generality of Men set their Affections on, when we know that there are a multitude of such Earths inhabited and adorn’d as well as our own.

Another analogy he made was comparing the way that light, sound, magnetism, and the percussion reverberations caused by a hammer blow all disseminate in a radiating pattern, often in waves. In one of his notebooks he made a column of small drawings showing how each force field spreads. He even illustrated what happened when each type of wave hits a small hole in the wall; prefiguring the studies done by Dutch physicist Christiaan Huygens almost two centuries later, he showed the diffraction that occurs as the waves go through the aperture. Wave mechanics were for him merely a passing curiosity, but even in this his brilliance is breathtaking.

Galileo essentially started out from where Archimedes left off, proceeding in the same direction as defined by his Greek predecessor. This is true not only of Galileo but also of the other great figures of the so-called “scientific revolution,” such as Leibniz, Huygens, Fermat, Descartes, and Newton. All of them were Archimedes’ children. With Newton, the science of the scientific revolution reached its perfection in a perfectly Archimedean form. Based on pure, elegant first principles and applying pure geometry, Newton deduced the rules governing the universe. All of later science is a consequence of the desire to generalize Newtonian, that is, Archimedean methods.

How vast those Orbs must be, and how inconsiderable this Earth, the Theatre upon which all our mighty Designs, all our Navigations, and all our Wars are transacted, is when compared to them. A very fit consideration, and matter of Reflection, for those Kings and Princes who sacrifice the Lives of so many People, only to flatter their Ambition in being Masters of some pitiful corner of this small Spot. —Christiaan Huygens, New Conjectures Concerning the Planetary Worlds, Their Inhabitants and Productions, c. 1690

A man that is of Copernicus’ Opinion, that this Earth of ours is a Planet, carry’d round and enlightn’d by the Sun, like the rest of them, cannot but sometimes have a fancy  …   that the rest of the Planets have their Dress and Furniture, nay and their Inhabitants too as well as this Earth of ours.… But we were always apt to conclude, that ’twas in vain to enquire after what Nature had been pleased to do there, seeing there was no likelihood of ever coming to an end of the Enquiry  …   but a while ago, thinking somewhat seriously on this matter (not that I count my self quicker sighted than those great Men [of the past], but that I had the happiness to live after most of them) me thoughts the Enquiry was not so impracticable nor the way so stopt up with Difficulties, but that there was very good room left for probable Conjectures.

Newton had conceived of light as primarily a stream of emitted particles. But by Einstein’s day, most scientists accepted the rival theory, propounded by Newton’s contemporary Christiaan Huygens, that light should be considered a wave. A wide variety of experiments had confirmed the wave theory by the late nineteenth century. For example, Thomas Young did a famous experiment, now replicated by high school students, showing how light passing through two slits produces an interference pattern that resembles that of water waves going through two slits. In each case, the crests and troughs of the waves emanating from each slit reinforce each other in some places and cancel each other out in some places.

For instance, we are regularly told, “James Watt invented the steam engine in 1769,” supposedly inspired by watching steam rise from a teakettle’s spout. Unfortunately for this splendid fiction, Watt actually got the idea for his particular steam engine while repairing a model of Thomas Newcomen’s steam engine, which Newcomen had invented 57 years earlier and of which over a hundred had been manufactured in England by the time of Watt’s repair work. Newcomen’s engine, in turn, followed the steam engine that the Englishman Thomas Savery patented in 1698, which followed the steam engine that the Frenchman Denis Papin designed (but did not build) around 1680, which in turn had precursors in the ideas of the Dutch scientist Christiaan Huygens and others. All this is not to deny that Watt greatly improved Newcomen’s engine (by incorporating a separate steam condenser and a double-acting cylinder), just as Newcomen had greatly improved Savery’s.

Queen Anne of England established the Longitude Act in 1714, and offered a monetary prize of over a million in today’s dollars to anyone who invented a method to accurately calculate longitude at sea. Longitude is about determining one’s point in space. So one might ask what it has to do with clocks? Mathematically speaking, space (distance) is the child of time and speed (distance equals time multiplied by speed). Thus, anything that moves at a constant speed can be used to calculate distance, provided one knows for how long it has been moving. Many things have constant speeds, including light, sound, and the rotation of the Earth. Your brain uses the near constancy of the speed of sound to calculate where sounds are coming from. As we have seen, you know someone is to your left or right because the sound of her voice takes approximately 0.6 milliseconds to travel from your left to your right ear. Using the delays it takes any given sound to arrive to your left and right ears allows the brain to figure out if the voice is coming directly from the left, the right, or somewhere in between. The Earth is rotating at a constant speed—one that results in a full rotation (360 degrees) every 24 hours. Thus there is a direct correspondence between degrees of longitude and time. Knowing how much time has elapsed is equivalent to knowing how much the Earth has turned: if you sit and read this book for one hour (1/24 of a day), the Earth has rotated 15 degrees (360/24). Thus, if you are sitting in the middle of the ocean at local noon, and you know it is 16:00 in Greenwich, then you are “4 hours from Greenwich”—exactly 60 degrees longitude from Greenwich. Problem solved. All one needs is a really good marine chronometer. The greatest minds of the seventeenth and eighteenth centuries could not overlook the longitude problem: Galileo Galilei, Blaise Pascal, Robert Hooke, Christiaan Huygens, Gottfried Leibniz, and Isaac Newton all devoted their attention to it. In the end, however, it was not a great scientist but one of the world’s foremost craftsman who ultimately was awarded the Longitude Prize. John Harrison (1693–1776) was a self-educated clockmaker who took obsessive dedication to the extreme.

Debido a su intuición de la unidad de la naturaleza, su mente, su ojo y su pluma se lanzaron a detectar relaciones saltando de una disciplina a otra. «Esta búsqueda constante de formas básicas, recurrentes y orgánicas suponía que, cuando miraba un corazón como un fruto rodeado de una red de venas, veía, y dibujaba a su lado, los brotes que germinan de una semilla —escribió Adam Gopnik—. Al estudiar los rizos de la cabeza de una bella mujer, pensaba en el movimiento circular de un remolino de agua.»[14] Su dibujo de un feto en el útero pone de manifiesto su parecido con una semilla dentro de la cáscara. Al inventar instrumentos musicales, Leonardo estableció una comparación entre el funcionamiento de la laringe y el glissando de una flauta. Al participar en el concurso de proyectos para el tiburio de la catedral de Milán, fijó una correspondencia entre arquitectos y médicos que reflejaba la analogía fundamental de su arte y su ciencia: la que existe entre el mundo físico y la anatomía humana. Al diseccionar una extremidad y dibujar sus músculos y tendones, trazaba asimismo cuerdas y palancas. Vimos un ejemplo de este análisis basado en pautas y patrones en la «hoja temática», en la que se disponía una relación de semejanza entre las ramas de un árbol y las arterias de un ser humano, que Leonardo también aplicaba a los ríos y sus afluentes. «La suma de todas las ramas de un árbol en cada una de sus distintas alturas resulta igual al grosor del tronco principal —escribió en otro lugar—. La suma de las ramificaciones de un curso de agua en cada uno de sus puntos, si fluyen con la misma rapidez, es igual al caudal de la corriente principal.»[15] Esta conclusión todavía se conoce como «regla de Da Vinci» y se ha demostrado cierta siempre que las ramas no sean muy grandes: la suma de las áreas transversales de todas las ramas en un determinado punto de ramificación equivale al área transversal del tronco o de la rama madre.[16] Otra analogía que hizo fue comparar la forma en que la luz, el sonido, el magnetismo y las reverberaciones causadas por un golpe de martillo se propagan siguiendo un patrón concéntrico, en general en forma de ondas. En uno de sus cuadernos realizó una serie de pequeños dibujos puestos en columna para indicar cómo se expande cada campo de fuerza. Incluso ilustró lo que sucedía cuando cada tipo de onda chocaba con un orificio en la pared; prefigurando los estudios que realizaría el físico neerlandés Christiaan Huygens al cabo de casi dos siglos, representó la difracción que se produce cuando las ondas atraviesan la abertura.[17] La mecánica de ondas constituyó para Leonardo una simple curiosidad pasajera, pero incluso en ella su genio parece asombroso. Las correlaciones que Leonardo establecía entre distintas disciplinas le servían para orientar sus investigaciones. La comparación entre los remolinos de agua y las turbulencias del aire, por ejemplo, le proporcionó el marco para estudiar el vuelo de las aves. «Con el fin de exponer la verdadera ciencia del vuelo de las aves en el aire —escribió—, tenemos que tratar primero de la ciencia de los vientos, que probaremos por el movimiento de las aguas.»[18] Aun así, los patrones que discernía eran más que simples guías útiles para el estudio. Los consideraba revelaciones de verdades esenciales, manifestaciones de la hermosa unidad de la naturaleza.

Back in 1698 Christiaan Huygens, a Dutch scientist who did pioneering work in optics, wrote ‘Why [should] not every one of these stars and suns have as great a retinue as our sun, of planets, with their moons to wait upon them?

Huygens las letter na letter in zijn eigen brief.

Huygens, best known as the first great horologist, swore he arrived at the idea for the pendulum clock independently of Galileo. And indeed he evinced a deeper understanding of the physics of pendulum swings—and the problem of keeping them going at a constant rate—when he built his first pendulum-regulated clock in 1656. Two years later Huygens published a treatise on its principles, called the Horologium, in which he declared his clock a fit instrument for establishing longitude at sea. By 1660, Huygens had completed not one but two marine timekeepers based on his principles.

Le vaisseau spatial Cassini-Huygens. Le vaisseau spatial renfermait des preuves sur l'existence des OVNIS que les États-Unis n’ont pas pu obtenir.   _____________________________________       Deux décennies plus tard, dans le lac Baïkal, d'autres nageurs de la marine russe ont rencontré des « nageurs argentés »

Huygens noticed one day that a set of pendulum clocks placed against a wall happened to be swinging in perfect chorus-line synchronization. He knew that the clocks could not be that accurate. Nothing in the mathematical description then available for a pendulum could explain this mysterious propagation of order from one pendulum to another. Huygens surmised, correctly, that the clocks were coordinated by vibrations transmitted through the wood. This phenomenon, in which one regular cycle locks into another, is now called entrainment, or mode locking. Mode locking explains why the moon always faces the earth, or more generally why satellites tend to spin in some whole-number ratio of their orbital period: 1 to 1, or 2 to 1, or 3 to 2. When the ratio is close to a whole number, nonlinearity in the tidal attraction of the satellite tends to lock it in. Mode locking occurs throughout electronics, making it possible, for example, for a radio receiver to lock in on signals even when there are small fluctuations in their frequency. Mode locking accounts for the ability of groups of oscillators, including biological oscillators, like heart cells and nerve cells, to work in synchronization. A spectacular example in nature is a Southeast Asian species of firefly that congregates in trees during mating periods, thousands at one time, blinking in a fantastic spectral harmony.

And so from then onwards, Daniel understood that the point of this grueling sundial project was not merely to plot the curve but to understand why each curve was shaped as it was. To put it another way, Isaac wanted to be able to walk up to a blank wall on a cloudy day, stab a gnomom into it, and draw all of the curves simply by knowing where shadow would pass. This was the same thing as knowing where the sun would be in the sky and that was the same as knowing where the Earth was in its circuit around the sun, and in its daily rotation. Though as months went on, Daniel understood that Isaac wanted to be able to do the same thing even if the blank wall happened to be situated on, say, the moon that Christiaan Huygens had lately discovered revolving around Saturn. Exactly how this might be accomplished was a question with ramifications that extended into such fields as would Isaac, and Daniel for that matter, be thrown out of Trinity College? Were the Earth and all the works of man nearing the end of a long, relentless decay that had begun with the expulsion from Eden, and that would very soon culminate in the apocalypse? Or might things actually be getting better, with the promise of continuing to do so? Did people have souls? Did they have free will?

See Cook [op.cit.] for a discussion of Huygens’s unusual wartime visit to Cambridge and the Royal Society. His philosophical contretemps with Isaac Newton in 1675 (referenced in Society minutes as “The Great Corpuscular Debate”) would mark the last significant intellectual discourse between England and the continent prior to the chaos of the Interregnum and the Annexation . . . Some Newton biographers [Winchester (1867), &c] indicate Huygens may have used his sojourn in Cambridge to access Newton’s alchemical journals and that key insights derived thusly may have been instrumental to Huygens’s monumental breakthrough. However, cf. Hooft [1909] and references therein for a critique of the forensic alchemy underlying this assertion. From Freeman, Thomas S., A History of the Pre-Annexation England from Hastings to the Glorious Revolution, 3 Vols. New Amsterdam: Elsevier, 1918.

Christiaan Huygens

rivalry between Huygens and Spinoza extended far beyond lenses and microscopes. For both men, the central issue in science at the time was to revise and refine Descartes’ laws of motion and mechanics. That

Huygens considered himself, Spinoza, and the Amsterdam regent-scientist, Johannes Hudde, the three leading specialists labouring to improve and extend its capabilities.

generally refers to Spinoza with a pinch of social disdain, as ‘nostre Juif’, ‘nostre Israelite’, ‘le Juif de Voorburg’, or simply ‘l’Israélite’, that Huygens and Spinoza disagreed about microscope lense sizes and curvatures. In deliberating with his brother, Huygens did not hide the fact that Spinoza was in some respects even more proficient with microscopes than he was himself

Newcomen’s engine borrowed the best features of its predecessors and incorporated new features of its own. It borrowed Huygens’s cylinder and piston but followed Papin in substituting steam for gunpowder. It borrowed from Savery the idea of condensing steam to make a vacuum. The Newcomen engine, however, unlike Papin’s or Savery’s, heated water to steam in a large, separate boiler, then piped the steam through a flap valve up to an open-ended cylinder mounted overhead. Instead of using steam pressure to push up the piston, as Papin had, Newcomen hung the piston from a massive wooden rocking beam so that the weight of the beam as it rocked pulled up the piston to open the cylinder between cycles.

The place of the study of communication in the history of science is neither trivial, fortuitous, nor new. Even before Newton such problems were current in physics, especially in the work of Fermat, Huygens, and Leibnitz, each of whom shared an interest in physics whose focus was not mechanics but optics, the communication of visual images.

Christiaan Huygens was the first to use Galileo’s insights to build the first high-quality pendulum clocks. A better mathematician than Galileo, he was able to truly comprehend the intricacies of the dynamics of a weight swinging back and forth on a string. Thanks to his mathematical skills and a number of technical innovations, the clock he designed in 1657 represented a quantum leap in timekeeping technology. Before Huygens, the best clocks were off by approximately 15 minutes a day; his clock lost a mere 10 seconds a day.8 Ten seconds amounts to approximately 0.01 percent of a 24-hour day. This level of accuracy marked a milestone in the history of timekeeping: these were the first clocks designed by the human brain that were better than the clocks within the human brain.

Pero la cicloide es también tautócrona. Esto le pareció a Johannes I algo maravilloso y admirable: "Con justicia podemos admirar a Huygens, por haber descubierto que una partícula pesada, describe una cicloide siempre en el mismo tiempo, cualquiera que sea el punto de partida.