Showing posts with label science. Show all posts
Showing posts with label science. Show all posts

Monday, December 26, 2011

early-modern science

It's generally pretty easy to distinguish fantasy from reality. We can tell the difference between intuited knowledge and knowledge gained through observation and careful measurement. We know that magicians perform tricks without aid from (probably diabolical) higher powers. Astrology and astronomy are to us two very different things; so too alchemy and chemistry, numerology and mathematics. But a few hundred years ago these distinctions were fuzzier.

As late medieval merged into early modern times, European men (almost always just men) started to correct serious mistakes that earlier generations had made about the natural world around them and the celestial bodies above. Some of these mistakes stemmed from religious beliefs, others from the writings of the ancient Greek philosophers and their successors. By questioning received authority, carefully examining natural phenomena, making complex mathematical calculations, and faithfully recording their findings these men transformed a scholastic philosophy into a new natural philosophy. The intellectual freedom achieved by this practice of scientific demonstration (as some of them were beginning to call it) was revolutionary in its magnitude, but not in the speed with which it took place.

Just as the transition from scholasticism and faith-based cosmology was evolutionary, so too the transition from belief in astrology, alchemy, and an ability to communicate with supernatural powers as legitimate tools for interacting with the natural world. Surprisingly, this second transition — scientists' rejection of hermetic beliefs — was even more gradual than their rejection of received truth from ancient authorities and of religious superstition (the "vain religion" of the schoolmen, as one of them put it).[1]

The men whom we now call scientists would study the real world using careful observation and rigorous measurement, but they would also, for example, use astrology to cast one another's natal charts. And the men and women who paid the bills — aristocratic or even royal patrons, wealthy merchants, and large land owners — expected their scientist clients to produce marvels — things out of the ordinary — to show off to their friends. Or, just as likely, they expected predictions of future events that might be advantageous to them.

On the sheet of paper I've reproduced below Galileo Galilei sketched the beginnings of a birth chart for a patron, Cosimo II, which Galileo used to show that Cosimo's future was an auspicious one. At the bottom of the page he drew the moon in its waxing phase at it appeared on January 19, 1609.

{Galileo’s sketch of the waxing Moon, as viewed on 19th January 1609 through his x20 telescope, on the same sheet as his first draft of the Cosimo II de Medici nativity; source: The Inspiration of Astronomical Phenomena, Proc. of 4th INSAP Conference, Oxford, Ed. N. Campion, Bristol 2004}

There are other instances of this service of natural philosophers to those they wished to flatter. For example Johannes Kepler created horoscopes for the Holy Roman Emperor, Rudolf II, and Tycho Brahe made annual charts for the Danish king, Fredrik, and the royal princes. Here is one of the birthday charts that Tycho Brahe made for Prince Christian in 1577.

{source: tychobrahesverden.dk}

Early modern natural philosophers and mathematicians would also prepare genitures for themselves and their friends. Without at first recognizing what they were, I encountered these tables when working in manuscript collections containing correspondence among Isaac Newton and other prominent mathematicians of the late seventeenth century. I also noticed that a writer of brief biographies, like the gossipy John Aubrey, might inquire about the exact moment of a man's birth, not having reason to do so except the making of an accurate birth chart for him.

{Detail from the entry for John Collins in "Brief lives", chiefly of contemporaries by John Aubrey, ed. by Andrew Clark, Andrew, Volume: 1 (Oxford, Clarendon Press, 1898)}

The Elizabethan magus, John Dee, presents an extreme example of a mathematician and astronomer who was also a self-proclaimed astrologer, alchemist, and practitioner of magic arts. Dee, among many other similar works, cast a horoscope to determine a favorable day for the coronation of Queen Elizabeth.[2] Here's a chart that John Dee made for himself.

{Natal chart made for himself by John Dee; source: C.U.R.A. The International Astrology Research Center}

Here's a final example of belief in astrology, astronomy, and magic persisting alongside the new natural philosophy. In the mid-1650s a man named John Webster (not the famous author but a chaplain of Parliamentarian forces in the English Civil War) wrote a book criticising the archaic curriculum of the English universities. In it he said the subjects taught were hopelessly — indeed dangerously — out-of-date and devoid of usefulness. Rather than forcing students to learn dead languages or memorize the writings of Aristotle and other ancient and more recent scholastic authors, he says they should be taught mathematics and experimental science.[3]

Webster says "Surely natural Philosophy hath a more noble, sublime, and ultimate end, than to rest in speculation, abstractive notions, mental operations, and verball disputes: for as it should lead us to know and understand the causes, properties, operations and affections of nature..." He acclaims applied mathematics — which, he points out, benefits merchants, mariners, surveyors, mechanics and others — and he condemns theoretical mathematics as merely speculative and abstract.[4] He heaps praise on chemistry, physics, and medicine as subjects of study that are "sublime, and never sufficiently praised."

But he gives as much in the way of accolades to the esoteric subjects of magic, alchemy, and astrology. He calls magic a "noble, and almost devine Science." To him, alchemy is "the most admirable and soul-ravishing knowledge of the three great Hypostatical principles of nature." And astrology is "high, noble, excellent, and useful." As you see in this extract, he lets himself be carried away on the subject.

{transcription: "What shall I say of the Science or art of Astrology, shall the blind fury of Misotechnists, and malicious spirits deter me from giving it the commendations that it deserves? shall the Acadamies who have not only sleighted and neglected it, but also scoffed at it, terrifie me from expressing my thoughts of so noble and beneficial a Science? shall the arguments of Picus Mirandula, and others, who have bitterly inveighed against it, fright me from owning the truth? shall the thundering Pulpit men, who would have all mens faith pinned upon their sleeves, and usually condemn all things they understand not, make me be silent in so just a cause? No truly, I must needs defend that which my judgment evidences to me to be laudable, and profitable; not but that I utterly condemn the ignorance, knavery, and impostorage of many pretending Sciolists, that abuse the same; but shall the art of medicine or Chymistry be condemned, and rejected, because many ignorant Empericks and false Alcumists do profess them? Surely no, let the blame be upon the protestors, not upon the profession it self. For the art it self is high, noble, excellent and useful to all mankind, and is a study not unbeseeming the best wits, and greatest Scholars, and no way offinsive to God or true Religion. And therefore I cannot, without detracting from worth and vertue, pass without a due Eulogy in the commendation of my learned and industrious Countrymen, Mr. Ashmole, Mr. William Lilly, Mr. Booker, Mr. Sanders, Mr. Culpepper, and others, who have taken unwearied pains for the resuscitation and promotion of this noble Science, and with much patience against many unworthy scandals have laboured to propagate it to posterity, and if it were not beyond the present scope I have in hand, I should have given sufficient reasons in the vindication of Astrology." [Acad. Examen, p. 51]; source: Academiarum examen, or the examination of academies wherein is discussed and examined the matter, method and customes of academick and scholastick learning by John Webster (Calvert, 1654)}

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Some sources:

"Celestial Offerings: Astrological Motifs in the Dedicatory Letters of Kepler's Astronomia Nova and Galileo's Sidereus Nuncius" by H. Darrel Rutkin in Secrets of nature: astrology and alchemy in early modern Europe ed. by Anthony Grafton (MIT Press, 2001)

Galileo's Astrology by Nick KIollerstrom on skyscript.co.uk

How Galileo Dedicated the Moons of Jupiter to Cosimo II de Medici by Nick Kollerstrom, The Inspiration of Astronomical Phenomena, Proc. of 4th INSAP Conference, Oxford, Ed. N. Campion, Bristol 2004, pp. 165-181.

Tycho Brahe och Astrology

John Dee's "Mathematicall Praeface": A Sixteenth Century Classification of the Mathematical Arts and Sciences by Charles St. Clair, Norman

The Mathematicall Praeface to Elements of Geometrie of Euclid of Megara by John Dee from Sir Henry Billingsley's first English version of Euclid's Elements, 1570

Isaac Newton and the Transmutation of Alchemy An Alternative View of the Scientific Revolution by Philip Ashley Fanning (North Atlantic Books, 2009)

Academiarum examen, or the examination of academies, wherein is discussed and examined the matter, method and customes of academick and scholastick learning by John Webster (London, Printed for Giles Calvert, 1654)

"Education" by J.W. Adamson in The Cambridge history of English literature , in 18 Volumes (1907–21) Volume IX, From Steele and Addison to Pope and Swift ed. by Adolphus Ward and Alfred Waller (Cambridge, the University Press, 1912)

"Brief lives", chiefly of contemporaries by John Aubrey, ed. by Andrew Clark, Andrew, Volume: 1 (Oxford, Clarendon Press, 1898)

"Brief Lives" by John Aubrey, ed. by Andrew Clark (Oxford, At the Clarendon Press, 1898)

Biographies in John Aubrey's Brief Lives

Only 26 and already a professor! in Renaissance Mathematicus

"Scientific Studies in the English Universities of the Seventeenth Century" by Phyllis Allen, Journal of the History of Ideas, Vol. 10, No. 2 (Apr., 1949) Stable URL: http://www.jstor.org/stable/2707416

"John Dee" by Thompson Cooper in Dictionary of national biography ed. by Leslie Stephen and Sidney Lee (Smith, Elder, & co., 1888)

"John Dee and His Supplication to Queen Mary" by P. Evans Lewin, Woolwich Public Libraries in The Library world, Vol. 5 (Library Supply Co., 1903) Extract: 'Whilst at Cambridge he only slept four hours every night, and spent eighteen hours of the day in study. So great was his knowledge, that his acquaintance was eagerly sought by such men as Gemma Frisius, Mercator, and Gaspar a Mirca, all of whom he visited in his twentyfirst year. Even at this period he was looked on askance, for he relates that in 1547 he "sett forth" at Trinity College a Greek comedy of Aristophanes, " with the performance of the Scarabaeus, his flying up to Jupiter's palace with a man and his basket of victuals on her back, whereat was great wondering and many vain reports spread about." This, probably, was only a piece of stage mechanism suitable to the crude ideas of the time and in keeping with Greene's instructions in "Tamburlaine "—" exit Venus; or if you can conveniently let a chair come down from the top of the stage and draw her up."'

"The Mistaking of 'the Mathematicks' for Magic in Tudor and Stuart England" by J. Peter Zetterberg in The Sixteenth Century Journal, Vol. 11, No. 1 (Spring, 1980), pp. 83-97. Stable URL: http://www.jstor.org/stable/2539477

"Science and Education in the Seventeenth Century: The Webster-Ward Debate" by G. Allen; reviewed by Theodore M. Brown in Isis, Vol. 64, No. 3 (Sep., 1973), pp. 422-424. (The University of Chicago Press) Stable URL: http://www.jstor.org/stable/229755

Hermeticism in wikipedia

John Aubrey in wikipedia

Brief Lives in wikipedia

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Notes:

[1] The quote comes from Academiarum examen, or the examination of academies, wherein is discussed and examined the matter, method and customes of academick and scholastick learning by John Webster (London, Printed for Giles Calvert, 1654)

[2] "John Dee" by Thompson Cooper in Dictionary of national biography ed. by Leslie Stephen and Sidney Lee (Smith, Elder, & co., 1888)

[3] Webster's diatribe was criticized by scholars who pointed to instances where the universities were teaching the new subjects. But as Phyllis Allen and others have pointed out the chief emphasis of education at Oxford and Cambridge remained as it had been. Mathematics and natural philosophy were emphatically secondary subjects of education. "As a rule, the tutor rather than the college had the greatest influence upon the student's work. A good tutor could do much for his pupil by making wise choices in the question of reading matter. Most tutors were not interested in the new experimental sciences, and some even overlooked the work of ancient scientists. One Cambridge tutor insisted that 'Mathematics and Natural Philosophy [were] not to be hurried.' Judging by the small amount of either that the average student seems to have learned, most tutors must rarely have found time to pursue these studies in an unhurried manner. ... Aside from these classics [Aristotle, Ptolomy, Euclid, ...] there were a few modern texts available. In algebra, the more advanced undergraduate could read Thomas Hariot's Artis Analyticae Praxis (London, 1631), in which he introduced Francis Vieta's methods to England. In arithmetic, a popular text was Edmund Wingate's Arithmetique Made Easie (London, 1630). For geometry, Henry Billingsley's translation of Euclid was used, together with Christopher Clavius' commentaries upon the same author, and John Speidell's Geometrical Extraction (London, 1616), which John Aubrey says "made young men have a love to geometry." -- "Scientific Studies in the English Universities of the Seventeenth Century" by Phyllis Allen, Journal of the History of Ideas, Vol. 10, No. 2 (Apr., 1949) Stable URL: http://www.jstor.org/stable/2707416

[4] Webster cites John Dee as a main source for his comments on the value of applied mathematics and praises him as "that myrror of manifold learning." -- Academiarum examen, or the examination of academies, wherein is discussed and examined the matter, method and customes of academick and scholastick learning by John Webster (London, Printed for Giles Calvert, 1654)

Wednesday, October 14, 2009

time present and time past are both perhaps present


{source: deviantart.com}

Yeah, but.... If "clocks exist" means — as I think it does — "we measure time," then we've gained immeasurably from those who first learned the trick. I can't imagine civilization evolving without clocks existing in this sense and, even with its attendant evils and discontents, civilization is better than the alternatives of which we know. To take one tiny example of clockism that leaps to mind, consider the "clock" that lies at the heart of every computer.

All the same, "time doesn't exist" is a nicely provocative conceit and there's ample warrant in philosophy and science for making that statement. Thus from a philosophic position, a man named John Ellis McTaggart could defend an assertion that "Time is unreal, and that all statements which involve its reality are erroneous."* And from a scientific one Einstein could write: "For those of us who believe in physics, this separation between past, present and future is only an illusion."**

McTaggart is not the only philosopher to assert that, despite appearances, time, or some aspect of time, is unreal. The argument is related to the radical idealist one that nothing exists outside the thought in my mind. It's akin the the theological position that since nothing exists that is not in the mind of God, God's mind is the only reality. I'm too pragmatic to take this seriously tho it's interesting to play with the idea.

Similarly, and more concretely, there is a considerable literature in which scientists discuss the unreality of time. When condensed into laymen's language these hypotheses are both fascinating and unnerving.

Supposing that we accept that time exists, if for no other reason than that otherwise we'd go batty, we still have difficulties explaining what it we mean by the term. Definitions are slippery.

For example, one of the problems both philosophers and scientists contend with is the paradox that our version of time goes forward but not backward; you can't really imagine Merlin living his life backwards from death to birth. As the author of an article in the Stanford Encyclopedia of Philosophy succinctly puts the matter, we perceive that "causation is asymmetric; later events cannot affect earlier ones, as a matter of mind-independent fact, and this is why we do not perceive the future, only the past." However, perception is the only evidence for this uni-directional movement. Philosophers have no compelling rationale for what's called temporal asymetry beyond asserting that this is the way things are. Meanwhile physicists have shown that this apriori statement is not true for all aspects of time: with regard to things very small (quantum mechanics) and very large (relativity) there is no temporal asymetry: time can be demonstrated to flow both forward and back.***

There's another way in which time is difficult to grasp. A group of experiments on the brain reveal that by the we become conscious of making a decision, we have in fact already made it. What we perceive to be happening in one time frame is actually happening in another. As the author of one study of this phenomenon puts it: "Our brains are shaping our decisions long before we become consciously aware of them... Patterns of activity in certain parts of our brain can predict the outcome of a decision seconds before we're even aware that we're making one."****

The first study of this nature was conducted by Benjamin Libet who found that a time lag of only about half a second, but others have shown that the delay between decision and conscious decision-making can be as long as ten seconds.

When I started this piece I thought I would proceed at this point to outline Henri Bergson's concept of duration, but think now that I'll leave that for another time.

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Some further reading:

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Notes:

*The Unreality of Time, by John Ellis McTaggart; published in Mind: A Quarterly Review of Psychology and Philosophy (17 (1908): 456-473).

**Quoted in: The Collider, the Particle and a Theory About Fate, by Dennis Overbye, New York Times, published: October 12, 2009. }

***The new theories that are killing time, an article in The Telegraph (UK)

**** Unconscious brain activity shapes our decisions

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{I couldn't find images that convey the way we perceive time to flow; this tries; source: pattondesignonline.com}


{source: vangrafx.com}


{Henri Bergson; source: wikipedia}

Wednesday, August 13, 2008

seal stories

I was intrigued by the following story in Agence France Presse. It interested me that elephant seals swim under the Antarctic ice floes and I appreciated the immaginative use of this behavior pattern. I was also surprised they didn't include a photo of these huge animals. Looking for a photo, I found another story, also cited below. I wasn't surprised that the current story didn't reference the earlier one, but wouldn't it be a good thing for reporters to do a little research so as to provide some additional background, and not just re-write what they're given in press releases?
Seals give scientists unique glimpse under Antarctic ice, by Lawrence Bartlett Tue Aug 12, 10:35 AM ET

extracts:

SYDNEY (AFP) - Huge elephant seals have been recruited to help scientists break through a critical blind spot and chart climate change under the Antarctic sea ice in winter, researchers said Tuesday.

The seals, which can weigh up to three tonnes, are fitted with sensors that transmit previously unavailable data to satellites when they surface to breathe.

The seals measure temperature, salinity and depth as they dive up to nearly two kilometres (1.25 miles) and cover distances of up to 65 kilometres a day.

They have provided a 30-fold increase in data over conventional methods.

The polar regions play an important role in the Earth's climate system and are changing more rapidly than any other part of the world, with the potential to accelerate the rate of change elsewhere, scientists say.

The sensors, about the size of a mobile phone, are fitted when the seals return to sub-Antarctic islands to breed and to moult during the summer.

Once they have grown the next season's fur, the sensors are glued to the fur on the back of the animal's head, so when it surfaces to breathe the sensor is out of the water and the antennae can transmit the data to satellite.

Though the seals are not particularly concerned about humans and scientists can approach them quite close, the animals are sedated with a syringe on the end of a pole to ensure the sensors can be attached safely.

The sensors stay on through the winter season and fall off when the seals return to the islands and shed their fur for the summer.
A quick search of Google Images turned up a large number of good photos. The most interesting was part of a NASA release which tells the story from a different viewpoint:
Mission News Satellites and Sea Lions: Working Together to Improve Ocean Models, by Rosemary Sullivant, 02.06.07

extracts:

The best oceanographers in the world never studied at a university. Yet they know how to navigate expertly along oceanic fronts, the invisible boundaries between waters of different temperatures and densities. These ocean experts can find rich fishing in places and at depths that others would assume are barren. They regularly visit the most interesting and dynamic parts of the sea.

Sea lions, seals, sharks, tuna and other top ocean predators share some of their experiences with human researchers, thanks to electronic tags. Besides tracking the animals, these sensors also collect oceanographic data, such as temperature and salinity. Scientists are beginning to incorporate this rich store of information into ocean models providing new insights into the inner workings of the ocean and the lives of its creatures.

"Our goal is to produce a three-dimensional model of the ocean," says JPL oceanographer Dr. Yi Chao. Chao uses data from satellites, ships, buoys and floats to map the currents, heat content and different water densities beneath the ocean surface.

"Satellites provide a two-dimensional view of the ocean," says Chao. "Animals give us a slice of the ocean. They're like weather balloons in reverse."

"We are at the forefront of knowing how animals use the ocean," says [Chao's collaborator] Costa. "But we want to understand the environment better. We still see the ocean primarily as deep or shallow or near-shore or offshore. But just as there are different habitats on land, the ocean has fine-scale features that are very important to animals," he explains. "We want to be able to look at the ocean and say the equivalent of "this is a grassland" or "this is a forest."

In late January, Costa and his research group headed up the California coast to begin tagging elephant seals and collecting tags that were deployed last spring. The work is strictly regulated to ensure that the animals are protected from harm, and it requires a permit from the National Marine Fisheries Service.

"Marine scientists have been tracking marine animals for years," says Chao. "It's an interesting challenge, though, to use the data. There are all sorts-- from tuna, sharks, seals--you name it. Some of these data sets have small errors, others much larger errors. Figuring out how to put these in our system is a challenge, "he says. "But five years from now, we should be able to see the ocean the way a turtle sees it."

What is most important about using marine animals as ocean sensors is that the work benefits the animals, Costa explains. "Collaborations between biologists and physical oceanographers are critical for understanding why the animals go where they go," he says, "as we need to know and understand the ocean physics and its relationship to climate processes. Further, the ability to understand how climate change is affecting the world oceans is not only of benefit to humans, but is vital for trying figure out what is going to happen to habitat of marine animals."
Here are a couple of images from the NASA site:

The field team attaches a tag to the fur of a sedated male elephant seal. Special permits are required for this work to ensure the animal's protection. Image credit: Daniel Costa


A male sea lion shares his intimate knowledge of the ocean with researchers via an electronic tag. Image credit: Mike Weise


And here are a couple more from Cathy Webster on her own web site.

South Georgia, St. Andrew's Bay, adult male elephant seal
12/16/2005



South Georgia, St. Andrew's Bay, me talking to a young elephant seal
12/17/2005