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Post by humphreyclarke on Feb 12, 2009 14:22:44 GMT
And you have yet to show why Alhazen's optical science did not follow the scientific method. What Al-Hasan ibn al-Haytham is doing is impressive and he was undoubtedly ‘the father of optics’. However, at the end of the day his work is still firmly in the Aristotelian mould. We can look at the work of any number of practitioners of Aristotelian science and see that it is empirical and observationally based, but it is somewhat anachronistic to see it as the same as the kind of experimental philosophy we arrive at during the ‘scientific revolution’. He still seems to be reading nature ‘uncritically’ so to speak, or in other words, making generalisations on the basis of common sense observations. The key is in the nature of the observation or experiment, in a modern sense this meant which interrogating nature and examining it time and time again under what are essentially “unnatural” or artificial conditions. Once you achieve these contrived conditions, you need communal observation and all kinds of different observations under different conditions, a long and complicated experimental process. What we have with Alhazan is hints of that; he does do experiential observations and measurements based on how light responds to refraction and reflection by mirrors, as well as how it can be split by a prism. Its not however the same leap forward we get in the 17th century as he is still explaining the properties of light by hypothesis rather than proposing and proving them by reason and a rigorous series of experiments. Its a subtle distinction but an important one. What was required was a different attitude to observation to that of Alhazan, more advanced equipment such as lenses and multiple prism arrays and the underlying philosophical attitudes underpinning it, such as a scepticism toward both the natural world and our faculties of observation. Of course it’s possible to do a fact based narrative, by looking at what was new about Alhazan, which says that he was the first true scientist and it looks like many have. But the fact remains that the scientific revolution did mark a leap forward in human thought, although it had deep roots in Greek, Medieval European and Islamic thought. Alhazan’s work was an important step along the way, but all the elements for modern science are not present; it is still recognisably Aristotelian. |
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Post by zameel on Feb 12, 2009 16:11:45 GMT
On Alhazen, the problem is we don't see a method but a series of unrelated investigations. He developed his hypothesis on vision but then did not test this. It clearly had problems and these should have been isolated and investigated The experimental method of testing hypotheses is found in Alhazen, e.g. in testing that light travels rectolinearly. As Omar Khaleefa (University of Newcastle Upon Tyne) writes (in defending the view that Alhazen was the first true experimental scientist): According to Sabra, the experiments in The Book of Optics, or most of them, are essentially different in form from both the repeated experiences of the physicians and the "comparisons" of the astronomers. To operate explicitly with such a distinct concept of experimental proof while regularly attaching it to a definite set of terms (i'tibar and its cognate), and thus dissociating it from the idea of accumulated experience or empeiria, was a significant conceptual development in the history of experimental science. [Sabra, Introduction, commentary, glossaries, concordance, indices of The Optics of Ibn al-Haytham, vol. 11, 18]
Ibn al-Haytham's Optics is a consistently mathematical and painstakingly empirical investigation of both light and vision. The hallmark of his unique style is his ability to resolve complex issues into closely interrelated series of experimental questions. Each specific problem is then subjected to a quantitative analysis of its variables under stringently controlled conditions. His series of experiments on the rectilinear propagation of light is a perfect illustration of his method. He uses a dark chamber with a small aperture in one wall to provide a point source of light. Filling the room with dust allows the beam of light to be both visualized and tested for linearity. Changing the atmosphere in the room (i.e., smoke instead of dust), gives the same result. Further checks are made using an inference procedure to disrupt the light beam. By this means he is able to show that light can only travel rectilinearly because the spot of light is only disrupted within a linear path; inference within curvilinear paths is ineffective. This use of the method of controlled observations is probably the first example of modern experimental design. [Russell, Ibn al-Haytham the First Biophysicist, viii]
His experiments with projected light images are of great importance for his hypotheses about vision and the eye. They provide us with what is, perhaps, the earliest version of the modern concept of conjugate points. In his implicit comparison of the eye with a pinhole camera, Ibn al-Haytham gives us the first modern synthesis of anatomy and optics. His conception of the eye as an optical system is best illustrated by his description of the lens and the optical axis of the eye. [Ibid, x] To operate consciously and systematically with a concept of experiment as a distinct method of proof, and not merely to perform or refer to experiments, was no doubt a significant landmark in the history of experimental science. [Sabra, "The Astronomical Origin of Ibn al-Haytham's Concept of Experiment, 136] Thus, during the eleventh century he associated psychology with physics or t\abi'a and relied purely on scientific observation as a method of investigation. In this respect he was the real founder of the i'tibar or the experimental method in the history of science in general. This fact contradicts what most historians of psychology have written, giving the major credit to F. Bacon. (Who Is the Founder of Psychophysics and Experimental Psychology? 2000) George Sarton wrote in his classic introduction to the history of science: "Ibn Haytham's writings reveal his fine development of the experimental faculty. His tables of corresponding angles of incidence and refraction of light passing from one medium to another show how closely he had approached discovering the law of constancy of ratio of sines, later attributed to Snell. He accounted correctly for twilight as due to atmospheric refraction, estimating the sun's depression to be 19 degrees below the horizon, at the commencement of the phenomenon in the mornings or at its termination in the evenings" Although he lacked lenses Alhazen did not lack lenses and he experimented on mirrors and lenses. continued to support Aristotelain precepts in mechanics Alhazen did not support Aristotle's mechanics. Nader Bezri writes: "He also presented a thorough critique of the conception of place (topos) as set in Aristotle’s Physics, wherein it was stated that the place of something is the two-dimensional boundary of the containing body that is at rest and is in contact with what it contains. In contrast with this definition, Ibn al-Haytham rather attempted to demonstrate in his Risala fi’l-makan (Treatise on Place) that place (al-makan) is the imagined three-dimensional void between the inner surfaces of the containing body. Consequently, he showed that place was akin to space in a manner that prefigures Descartes’ extensio." Roshdi Rashed showed Alhazen did not make use of Aristotelian physics or cosmology in developing the field of celestial kinematics, see: The Celestial Kinematics of Ibn al-Haytham (2007) (available at journals.cambridge.org/)His Doubts About Ptolemy led to the revolution in astronomy in the following centuries. Ibn al-Haytham also proposed a different model to Aristotle for the explanation of the rainbow, which although incorrect, provided the basis for the successful (and correct) model of Kamal al-Din al-Farisi, see: HG Topdemir, Kamal al-Din al-Farisi’s Explanation of the Rainbow, 2007. In fact the correct explanation of the rainbow was achieved simultaneously in Europe and in the Islamic world in the thirteenth century as a result of Ibn al-Haytham’s Book of Optics. despite their brilliant astronomical observations remained wedded to an erroneous metaphysical view of the heavens No they didn't. Al-Biruni in the tenth century forewent Aristotle's distinction between the perfect supralunar and the imperfect sublunar worlds, and a universal physics was developed by Alhazen and Avicenna amongst others. never took to accurate measurement in chemistry Rhazes refuted Aristotle's theory of four elements, Ja'far Sadiq proposed the existence of multiple elements and the transmutation of metals was refuted by most Arabic chemists including Ja'far Sadiq, Biruni, Alkindus, Avicenna and Ibn Khaldun. that heavy objects fall the same speed of light ones Alhazen did propose a crude version of Newton's First Law Pythagoreans had no problem with this and al-Biruni was neutral (on scientific, as opposed to philosophical grounds) in regards to heliocentricism and geocentricism. The famous astronomer al-Shirazi (d. 1311) also discussed heliocentricism and the earth's movement as a possibility. Hence I do not see how your condition for modern science that "science can be both rational and defy common sense" is helpful. Your argumentation involves consistently moving the goalposts when one element of a mysterious "modern science" is disproven - what if that singularity doesn't exist? |
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Post by James Hannam on Feb 12, 2009 16:36:40 GMT
Zameel,
If everything you wrote was an accurate reflection of history, then the scientific revolution would have occurred in Baghdad in the tenth century and I would be lamely claiming the importance of Newton and Einstein in the development of all-conquering Islamic science.
Once again, we must agree to disagree.
Best wishes
James
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Post by zameel on Feb 12, 2009 17:06:21 GMT
Zameel, If everything you wrote was an accurate reflection of history, then the scientific revolution would have occurred in Baghdad in the tenth century and I would be lamely claiming the importance of Newton and Einstein in the development of all-conquering Islamic science. Once again, we must agree to disagree. Best wishes James What is "the scientific revolution" besides a romanticising of Western history? Modern historians question its existence as such: many of the "scientists" during the revolution were not practicing science but magic, alchemy, theology, astrology and the like; and the "revolution", particularly the Copernican "revolution", in fact represents a continuity of scientific thought from Tusi's Maragheh School and is thus not a revolution. Why does "the scientific revolution" have to exist? Why does the fact that we find authentic scientific achievements in the Islamic era in any way invalidate Newton's or Einstein's genius? And what facts do you dispute in what I wrote above? |
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Post by James Hannam on Feb 12, 2009 17:25:52 GMT
What is "the scientific revolution" besides a romanticising of Western history? Modern historians question its existence as such: many of the "scientists" during the revolution were not practicing science but magic, alchemy, theology, astrology and the like; and the "revolution", particularly the Copernican "revolution", in fact represents a continuity of scientific thought from Tusi's Maragheh School and is thus not a revolution. Why does "the scientific revolution" have to exist? Why does the fact that we find authentic scientific achievements in the Islamic era in any way invalidate Newton's or Einstein's genius? And what facts do you dispute in what I wrote above? Nothing. But it is not what you have been saying up to now. And yes, I am extremely sceptical about the historicographical concept of the scientific revolution. You have consistently claimed that modern science began in the Islamic caliphate. You have also claimed modern (that is post-medieval ideas) for medieval thinkers. That is untrue and anchronistic, but it is certainly the case that theirs were authentic scientific achievements. You just need to accept that Islamic natural philosophy was a step on the way to modern science, but the journey was not completed until the nineteenth century. Furthermore, as we would expect, many avenues turned out to be dead ends, especially in the case of medicine. Finally, clinging to untenable beliefs about Geber does not do any good. Best wishes James |
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Post by zameel on Feb 12, 2009 17:56:11 GMT
You just need to accept that Islamic natural philosophy was a step on the way to modern science, but the journey was not completed until the nineteenth century. You maintain that a distinctly 'modern science' does exist, not in a temporal but an ahistorical absolute sense. What is distinct about the science today that was not present in Arabic science? This is not considering scientific results, but the process and progress of the scientific activity. As an aside, my supervisor on Theology and Science in Cambridge, Philip Luscombe, agrees with me that a distinct modern science does not exist, but he thinks the professionalisation of science by Thomas Huxley and others led to the marked acceleration of science in the twentieth century. Finally, clinging to untenable beliefs about Geber does not do any good Which belief is untenable? - I provided Ahmad Y Hassan's extensive research on the topic |
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Post by James Hannam on Feb 13, 2009 13:57:50 GMT
You maintain that a distinctly 'modern science' does exist, not in a temporal but an ahistorical absolute sense. What is distinct about the science today that was not present in Arabic science? This is not considering scientific results, but the process and progress of the scientific activity. In a wholly random order (most of these are 19th century developments though): Professionalisation and training in the tradition; Lack of metaphysics or at least unthinking acceptance of methodological naturalism; Science as the final arbitrator of truth; Self regulation (only scientists can arbitrate the claims of scientists); Science feeding into technology; Science seen as a self-evident good; Industrialisation of laboratory processes; Double blind testing; Testing against the nul hypothesis; Autonomous scientific institutions; Statistical analysis; Unification of the sciences (as both an aim and a method of organisation); and Science as an alternative to religion. As an aside, I have a Cambridge PhD too, but mine's in History and Philosophy of Science. Which belief is untenable? - I provided Ahmad Y Hassan's extensive research on the topic Which, believe it or not, I read. He doesn;t deal with the detailed textual analysis that takes up the first hundred pages or so of Newman's edition of Summa Perfectionis, nor Kraus's. This has been examined carefully of late and you may find this of interest. Note this author asserts the Latin Geber corpus is not from an Arabic source. See also Donald Hill's article in the Cambridge History of Arabic Lit : The 'Abbasid Period. Best wishes James |
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Post by zameel on Feb 13, 2009 21:33:31 GMT
In a wholly random order (most of these are 19th century developments though): Professionalisation and training in the tradition; Lack of metaphysics or at least unthinking acceptance of methodological naturalism; Science as the final arbitrator of truth; Self regulation (only scientists can arbitrate the claims of scientists); Science feeding into technology; Science seen as a self-evident good; Industrialisation of laboratory processes; Double blind testing; Testing against the nul hypothesis; Autonomous scientific institutions; Statistical analysis; Unification of the sciences (as both an aim and a method of organisation); and Science as an alternative to religion. Your list demonstrates the futility of the need to defend a singularity for 'modern science'. Most of these have nothing to do with science but external sociological conditions (e.g. professionalisation, industralisation, institutionalisation), none of which I disagree with and if you want to call that 'modern science' I have no problem with it, but it should be kept in mind these have no bearing on the science itself. If in order to find unique unprecedented science we have merely to combine a number of (perhaps irrelevant) factors supposedly new to that time, the same could be done with any other mundane event; we could talk of 'modern tea' as we now have various different brands, corporations and industries, but notice that the tea hasn't changed. If it were a matter of a number of scientific principles having accrued to that date to give the science a historic epoch, similar things could be done to other eras, e.g. we could say Arabic science was a particular distinct 'millenial science' wherein such distinctions like a common lingua franca for science, scientific experimentation for testing hypotheses, skepticism and doubt of earlier science, the method of quarantine and knowledge of infection etc. were newly introduced. Some of your conditions are vague or untrue, like 'science feeding into technology' (which was arguably always true) and 'science as the final arbitrator to truth' (which is false in a postmodern world and may have only been temporarily true - so by your standards, modern science is modern science no longer, unless you play the casual game of moving the goal posts every time a particular condition (like experimentation and skepticism before) is falsified). And your relevant points in fact demonstrate continuity of scientific thought. Double blind experiments were probably first carried out in the eighteenth century by Benjamin Franklin (see: Kaptchuk, Intentional Ignorance: A History of Blind Assessment and Placebo Controls in Medicine, 1998) and statistical analysis dates back to Al-Kindi in the ninth century predating Pascal and Fermat in the seventeenth century. Furthermore separation of science from religion and personal whim was achieved much earlier by Arabic scientists as shown in Dimitri Gutas's paper on the epistemological foundations of Arabic science. Although there was no institutional separation, the scientists were aware they were doing something different to other activities like philosophy, metaphysics and theology; this is particularly true for astronomy and physics (optics). He doesn;t deal with the detailed textual analysis that takes up the first hundred pages or so of Newman's edition of Summa Perfectionis, nor Kraus's. This has been examined carefully of late and you may find this of interest. Note this author asserts the Latin Geber corpus is not from an Arabic source AY Hassan does not deny the fancies of many Western historians (although notable exceptions do exist like Holmyart, James Partington and presently Fuat Sezgin). But he highlights the bankruptcy of many of their assumptions, including Newman's and Kraus's (he deals with Kraus here: www.history-science-technology.com/Geber/Geber%203.htm). Can you give an example of textual criticism which you think Hassan does not address? Besides, do you dispute his evidence for nitric acid being isolated by Arabic scientists before the thirteenth century, which was your main point anyway? |
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