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== '''[[Alcmaeon of Croton]]''' ==
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''by [[User:Anthony.Sebastian|Anthony.Sebastian]]
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==Footnotes==
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'''Alcmaeon''', also '''Alcmaeon of Croton''', was an ancient Greek early-vintage [[natural philosopher]].<ref><font face="Gill Sans MT"><u>Note:</u>
*Today scholars recognize 'natural philosophers' as early scientists, seeking rational explanations of phenomena observable on Earth and in the sky, often confining their explanations to hypothetical (theoretical) constructs, over time developing sophisticated and methodical observations, initiating experimental techniques, and engaging in commentary and criticism of each others' works. Scholars consider [[Thales|Thales of Miletus]], who flourished in the 6th century BCE, as the progenitor of natural philosophy, postulating water as the 'elementary' substance underlying all matter. [[Isaac Newton]] (1643-1727), whom we call today a mathematician and physicist, published his signal work in physics as <i>The Mathematical Principles of Natural Philosophy</i>.</font></ref> Alcmaeon had a wide spectrum of interests in natural phenomena (astronomical, anatomical, biological, cognitive, medical, ''inter alia''), offering explanations of them in rational mechanistic terms as opposed to the prevailing explanations in terms of supernatural forces, and he had a particular interest in medicine and physiology.<ref name=huffmansep2008>Huffman, Carl, "Alcmaeon", The Stanford Encyclopedia of Philosophy (Winter 2008 Edition), Edward N. Zalta (ed.), [http://plato.stanford.edu/archives/win2008/entries/alcmaeon/ Full-Text of Article.]
*<font face="Gill Sans MT">An extensive treatment of Almaeon's thinking and relationship to ancient Greek natural philosophy.</font></ref>
 
Longrigg states that of the medical theories of those natural philosophers in the era before [[Hippocrates|Hippocrates of Kos]] (who, with his disciples, left an extensive body of writings known as the Hippocratic treatises), only those of Alcmaeon have survived to any significant extent.<ref name=longrigg1993/>
 
Ancient and modern scholars generally hold Alcmaeon in high esteem as an innovative thinker, as the originator or early proponent of the rationalistic explanation of health and disease, as an experimentalist, and as having a major influence on the development of Western medicine, in part through his influence on [[Hippocrates]] and his disciples.<ref name=longrigg1993/> "''[Alcmaeon's] anatomical researches, particularly into the structure of the eye, and his connecting the senses with the brain...mark him as a pioneer in pure medical science.''"<ref name=jonesphilmed>Jones WHS. (1979) [http://books.google.com/books?id=vaNMb8UssUgC&dq=Alcmaeon&source=gbs_navlinks_s Philosophy and medicine in ancient Greece: with an edition of Peri archaiēs iētrikēs]. Volume 8 of Johns Hopkins University Press reprints. Issue 8 of Bulletin of the History of Medicine. Supplements. Issue 8 of Henry E. Sigerist supplements to the Bulletin of the History of Medicine. Ayer Publishing. ISBN 9780405106064.</ref> Scholars have credited Alcmaeon as the first person to recognize the brain as the organ of sense perception, of intelligence, and as the seat of the mind.<ref name=doty2007>Doty RW. (2007) [http://dx.doi.org/10.1016/j.neuroscience.2007.02.046 Alkmaion's discovery that brain creates mind: a revolution in human knowledge comparable to that of Copernicus and of Darwin]. ''Neuroscience'' 147:561-8.
*<font face="Gill Sans MT"><u>Abstract:</u> Without special examination the brain offers no clue that it is the organ of the mind. From the dawn of time man thus either ignored the problem as to the source of thought, or attributed it to a variety of anatomical structures, usually the heart. The brain held no place in such intuitions, and in most languages it is analogized to bone marrow. Furthermore, nothing in early medical systems claimed any intellectual capacity for the brain;  the Egyptians, so fastidious in care for their afterlife, heedlessly discarded the brain in funerary practice. It was thus a unique event in world history when Alkmaion of Kroton (Alcmaeon, ca. 500 bc), based on anatomical evidence, proposed that the brain was essential for perception. Although no writings of Alkmaion survived, it was probably via a fortuitous linkage that his idea of the mental primacy of the brain was transmitted to, and preserved within, the teachings of the Hippocratic school. Nothing, of course, was secure as to mechanism, two millennia unfolding until the search for mind passed from the ventricles to the cerebral cortex. Nonetheless, Alkmaion was the beginning, and the ensuing understanding that he initiated is still transforming humanity's perception of the natural world, and their place within it.</font></ref> <ref name=debernardi>Debernardi A, Sala E, D'Aliberti G, Talamonti G, Franchini AF, Collice M. (2010) [http://www.ncbi.nlm.nih.gov/pubmed/20087125 Alcmaeon of Croton]. ''Neurosurgery'' 66:247-52 | [http://journals.lww.com/neurosurgery/Fulltext/2010/02000/Alcmaeon_of_Croton.11.aspx Free Full-Text].
*<font face="Gill Sans MT"><u>Abstract:</u> IN THE LATTER half of the sixth century BC, Croton was the site of the most famous medical school in Magna Graecia, where diseases of the human body were examined in a scientific and experimental manner instead of by using the contemporary supernatural, nearly magical concepts. Alcmaeon was one of the most active physicians interested in human physiology in the medical tradition of Croton. Although Alcmaeon was devoted to science and was a skillful experimentalist, little is known about his life and his exact birth date. The relative isolation of Alcmaeon from the great philosophical currents of his time probably facilitated his unprejudiced methodology and may have prevented him from disclosing his theories and demonstrating their value. He pioneered the concept of the relationship between the brain and the mind and was the first to identify the brain as the center of understanding and the essential organ for perceptions, sensations, and thoughts. Through systematic observations, Alcmaeon brought many things to light about the characteristics of the eye and the presence of channels connecting head sensory organs to the brain. He stated that the soul was immortal and introduced the tekmairesthai doctrine, through which the ideas of anamnesis and prognosis gave birth. We highlight his contributions to medical thought, and especially to neuroscience, which reveal Alcmaeon to be a thinker of considerable originality and one of the greatest philosophers, naturalists, and neuroscientists of all time.</font></ref>
 
Alcmaeon was born in about 515 BCE and  lived sometime in the 500s BCE in the Greek city of Croton in Italy. Alcmaeon lived during and near the times of [[Pythagorus]] (ca. 570 – 490 BCE), also in Croton, and before [[Hippocrates|Hippocrates of Kos]] (460 – ca. 370 BCE).<ref name=nuttonancientmed>Nutton V. (2004) [http://www.questia.com/read/107508313 Ancient Medicine.] New York: Routledge
*<u>Nutton states:</u> <font face="Gill Sans MT">Whether he [Alcmaeon] flourished in the late sixth century BC [close to 500 BC]  or a generation or so later, in the second quarter of the fifth  [475-450 BC], is disputed. Tradition claimed him as a pupil of  Pythagoras [c.582–c.507 BC] 'in his old age', but the textual and  historical basis for this assertion is far from sound, and Alcmaeon's  interests and the sophistication of some of his methods are better  suited to the later date.</font></ref> <ref name=longrigg1993>Longrigg J. (1993) [http://www.questia.com/read/103416571 Greek Rational Medicine: Philosophy and Medicine from Alcmaeon to the Alexandrians.] New York: Routledge.
*<u>Longrigg states:</u> <font face="Gill Sans MT">while  a precise dating is impossible upon the available evidence, a period of  activity around the second quarter of the fifth century BC would pose  no insurmountable chronological problem with regard to the theories and  views attributed to Alcmaeon.
*Longrigg gives a detail examination of the evidence for the dating of Alcmaeon’s life.</font></ref> <ref name=huffmansep2008/>&nbsp;<ref>[http://www.britannica.com/EBchecked/topic/13331/Alcmaeon Alcmaeon (2009) In Encyclopædia Britannica.] Retrieved November 07, 2009, from Encyclopædia Britannica Online.</font></ref>
 
===Contributions of Alcmaeon===
 
[[Vesalius|Andreas Vesalius’s]]  biographer, C. D. O’Malley, credits Alcmaeon as the earliest known “genuine student of anatomy”:
<blockquote>The earliest known genuine student of anatomy appears to have been Alcmaeon  of Crotona, who lived in southern Italy, c. 500 B.C. Only the slightest fragments of his writing remain, but from these it does appear that he was the first to make dissections of animals, probably goats, and although almost nothing is known of the results, he did make the very important declaration that the brain is the central organ  of intelligence.<ref name=omalley1964>O'Malley CD. (1964) Andreas Vesalius of Brussels, 1514-1564. Berkeley: University of California Press.
*<u>Note:</u>&nbsp;<font face="Gill Sans MT">Considered the definitive biography. Renown historian of medicine, F. N. L. Poynter, stated of Dr. O'Malley's book: "What strikes me immediately on reading Professor O'Malley's monumental work is the coolness of its judgment, the absence of any kind of special pleading or even of that warmth of expression which comes from the biographer's identification with his subject. This almost Olympian detachment is rare indeed and not to be found in any of the outstanding examples of the biographer's art which readily spring to mind." (See F. N. L. POYNTER. 1964. [http://dx.doi.org/10.1093/jhmas/XIX.4.321 Andreas Vesalius of Brussels — 1514-1564: A Brief Survey of Recent Work.] Journal of the History of Medicine and Allied Sciences 1964 XIX(4):321-326. PMID 14215447</font></ref></blockquote>
 
J. B. Wilbur and H. J. Allen give this introduction to Alcmaeon:
<blockquote>Physiology and medicine were Alcmaeon's prime interest, which accounts for his concern with cognition and the nature of the soul. Because medicine had not yet emerged as a distinct discipline, however, Alcmaeon also expressed opinions on the immortality of the soul as well as on astronomy and cosmology--thus going beyond the limitations of his own medical empiricism. There are no fragments and little other information concerning his views on these last two subjects, but in any case it would seem that Alcmaeon's contributions are his ideas concerning knowledge and the soul.<ref name=wilburallen>Wilbur JB, Allen HJ. (1979) [http://www.questia.com/read/82239065 The Worlds of the Early Greek Philosophers.] Prometheus Books: Buffalo, NY.
*<u>About this book, from its Preface:</u>&nbsp;<font face="Gill Sans MT">The authors of this book have tried to do two things in presenting the written materials ascribed to the early Greek philosophers (c. 585 B.C.-400 B.C.) and the historical context in which those writings occurred. The first was to present a more fully fleshed out picture of the ideas of these men than has been given in the past. Perhaps under the influence of a narrow empiricism there has been a preference for letting the fragments speak for themselves. The trouble with this approach is that, even where there is a goodly number of fragments left, as, for instance, by Heraclitus, an adequate context for interpretation is not always evident from the fragments alone. And in the case of a thinker such as Anaximander, on the other hand, where there is so little firsthand evidence, what does remain is obscure taken solely on its own terms. Opposed to this Scylla of parsimony, there is, of course, the Charybdis of prodigal speculation. But we did not wish to hew a predetermined course equidistant from these two extremes. Rather the goal was to suit our passage to the winds and waters, sometimes nearer one than the other, as seemed best....The second aim, also in the nature of a mean between extremes, was to find a happy balance between overwhelming the reader with all the scholarly paraphernalia of etymology and philology, and presenting a stripped-down version of the ideas that conveys no sense of the condition and source of our knowledge about them. While, for all but the specialist, the former detracts from the ideas presented, the latter fails to give a proper appreciation of the subject. In practice, this means that we<tried to indicate, whenever possible, who attributed an idea to a given philosopher while at the same time providing the student with the relevant passage so he can read for himself what, for instance, Heraclitus said about Pythagoras. For this reason, the fragments themselves as well as essential interpretive passages are included in the text. Testimonials by other thinkers, which are of great importance to our knowledge of the earliest of these Greek philosophers, are either included in the body of the text or referred to at the bottom of the page, depending upon their relevance. A guide to these testimonial sources appears at the end of the book, along with a selected bibliography for the period as well as for the thinkers.</font></ref></blockquote>
 
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Latest revision as of 09:19, 11 September 2020

After decades of failure to slow the rising global consumption of coal, oil and gas,[1] many countries have proceeded as of 2024 to reconsider nuclear power in order to lower the demand for fossil fuels.[2] Wind and solar power alone, without large-scale storage for these intermittent sources, are unlikely to meet the world's needs for reliable energy.[3][4][5] See Figures 1 and 2 on the magnitude of the world energy challenge.

Nuclear power plants that use nuclear reactors to create electricity could provide the abundant, zero-carbon, dispatchable[6] energy needed for a low-carbon future, but not by simply building more of what we already have. New innovative designs for nuclear reactors are needed to avoid the problems of the past.

(CC) Image: Geoff Russell
Fig.1 Electricity consumption may soon double, mostly from coal-fired power plants in the developing world.[7]

Issues Confronting the Nuclear Industry

New reactor designers have sought to address issues that have prevented the acceptance of nuclear power, including safety, waste management, weapons proliferation, and cost. This article will summarize the questions that have been raised and the criteria that have been established for evaluating these designs. Answers to these questions will be provided by the designers of these reactors in the articles on their designs. Further debate will be provided in the Discussion and the Debate Guide pages of those articles.

Footnotes

  1. Global Energy Growth by Our World In Data
  2. Countries, organizations, and public figures that have reconsidered their stance on nuclear power are listed on the External Links tab of this article.
  3. Pumped storage is currently the most economical way to store electricity, but it requires a large reservoir on a nearby hill or in an abandoned mine. Li-ion battery systems at $500 per KWh are not practical for utility-scale storage. See Energy Storage for a summary of other alternatives.
  4. Utilities that include wind and solar power in their grid must have non-intermittent generating capacity (typically fossil fuels) to handle maximum demand for several days. They can save on fuel, but the cost of the plant is the same with or without intermittent sources.
  5. Mark Jacobson believes that long-distance transmission lines can provide an alternative to costly storage. See the bibliography for more on this proposal and the critique by Christopher Clack.
  6. "Load following" is the term used by utilities, and is important when there is a lot of wind and solar on the grid. Some reactors are not able to do this.
  7. Fig.1.3 in Devanney "Why Nuclear Power has been a Flop"