Ì«×ÓүС˵Íø > Ó¢Óïµç×ÓÊé > a history of science-1 >

µÚ27½Ú

a history of science-1-µÚ27½Ú

С˵£º a history of science-1 ×ÖÊý£º ÿҳ4000×Ö

°´¼üÅÌÉÏ·½Ïò¼ü ¡û »ò ¡ú ¿É¿ìËÙÉÏÏ·­Ò³£¬°´¼üÅÌÉ쵀 Enter ¼ü¿É»Øµ½±¾ÊéĿ¼ҳ£¬°´¼üÅÌÉÏ·½Ïò¼ü ¡ü ¿É»Øµ½±¾Ò³¶¥²¿£¡
¡ª¡ª¡ª¡ªÎ´ÔĶÁÍꣿ¼ÓÈëÊéÇ©ÒѱãÏ´μÌÐøÔĶÁ£¡



ly¡¡logical¡¡induction¡¡when¡¡he¡¡propounded¡¡the¡¡theory¡¡that¡¡the¡¡stars¡¡in¡¡the¡¡Milky¡¡Way¡¡seem¡¡more¡¡numerous¡¡and¡¡brighter¡¡than¡¡those¡¡of¡¡any¡¡other¡¡part¡¡of¡¡the¡¡heavens£»¡¡merely¡¡because¡¡the¡¡Milky¡¡Way¡¡marks¡¡the¡¡shadow¡¡of¡¡the¡¡earth¡£¡¡Of¡¡course¡¡the¡¡inference¡¡was¡¡wrong£»¡¡so¡¡far¡¡as¡¡the¡¡shadow¡¡of¡¡the¡¡earth¡¡is¡¡concerned£»¡¡yet¡¡it¡¡contained¡¡a¡¡part¡¡truth£»¡¡the¡¡force¡¡of¡¡which¡¡was¡¡never¡¡fully¡¡recognized¡¡until¡¡the¡¡time¡¡of¡¡Galileo¡£¡¡This¡¡consists¡¡in¡¡the¡¡assertion¡¡that¡¡the¡¡brightness¡¡of¡¡the¡¡Milky¡¡Way¡¡is¡¡merely¡¡due¡¡to¡¡the¡¡glow¡¡of¡¡many¡¡stars¡£¡¡The¡¡shadow¡­¡¡theory¡¡of¡¡Anaxagoras¡¡would¡¡naturally¡¡cease¡¡to¡¡have¡¡validity¡¡so¡¡soon¡¡as¡¡the¡¡sphericity¡¡of¡¡the¡¡earth¡¡was¡¡proved£»¡¡and¡¡with¡¡it£»¡¡seemingly£»¡¡fell¡¡for¡¡the¡¡time¡¡the¡¡companion¡¡theory¡¡that¡¡the¡¡Milky¡¡Way¡¡is¡¡made¡¡up¡¡of¡¡a¡¡multitude¡¡of¡¡stars¡£¡¡It¡¡has¡¡been¡¡said¡¡by¡¡a¡¡modern¡¡critic£§1£§¡¡that¡¡the¡¡shadow¡­theory¡¡was¡¡childish¡¡in¡¡that¡¡it¡¡failed¡¡to¡¡note¡¡that¡¡the¡¡Milky¡¡Way¡¡does¡¡not¡¡follow¡¡the¡¡course¡¡of¡¡the¡¡ecliptic¡£¡¡But¡¡this¡¡criticism¡¡only¡¡holds¡¡good¡¡so¡¡long¡¡as¡¡we¡¡reflect¡¡on¡¡the¡¡true¡¡character¡¡of¡¡the¡¡earth¡¡as¡¡a¡¡symmetrical¡¡body¡¡poised¡¡in¡¡space¡£¡¡It¡¡is¡¡quite¡¡possible¡¡to¡¡conceive¡¡a¡¡body¡¡occupying¡¡the¡¡position¡¡of¡¡the¡¡earth¡¡with¡¡reference¡¡to¡¡the¡¡sun¡¡which¡¡would¡¡cast¡¡a¡¡shadow¡¡having¡¡such¡¡a¡¡tenuous¡¡form¡¡as¡¡the¡¡Milky¡¡Way¡¡presents¡£¡¡Such¡¡a¡¡body¡¡obviously¡¡would¡¡not¡¡be¡¡a¡¡globe£»¡¡but¡¡a¡¡long¡­drawn¡­out£»¡¡attenuated¡¡figure¡£¡¡There¡¡is£»¡¡to¡¡be¡¡sure£»¡¡no¡¡direct¡¡evidence¡¡preserved¡¡to¡¡show¡¡that¡¡Anaxagoras¡¡conceived¡¡the¡¡world¡¡to¡¡present¡¡such¡¡a¡¡figure¡¡as¡¡this£»¡¡but¡¡what¡¡we¡¡know¡¡of¡¡that¡¡philosopher's¡¡close¡­reasoning£»¡¡logical¡¡mind¡¡gives¡¡some¡¡warrant¡¡to¡¡the¡¡assumptiongratuitous¡¡though¡¡in¡¡a¡¡sense¡¡it¡¡be¡¡that¡¡the¡¡author¡¡of¡¡the¡¡theory¡¡of¡¡the¡¡moon's¡¡phases¡¡had¡¡not¡¡failed¡¡to¡¡ask¡¡himself¡¡what¡¡must¡¡be¡¡the¡¡form¡¡of¡¡that¡¡terrestrial¡¡body¡¡which¡¡could¡¡cast¡¡the¡¡tenuous¡¡shadow¡¡of¡¡the¡¡Milky¡¡Way¡£¡¡Moreover£»¡¡we¡¡must¡¡recall¡¡that¡¡the¡¡habitable¡¡earth£»¡¡as¡¡known¡¡to¡¡the¡¡Greeks¡¡of¡¡that¡¡day£»¡¡was¡¡a¡¡relatively¡¡narrow¡¡band¡¡of¡¡territory£»¡¡stretching¡¡far¡¡to¡¡the¡¡east¡¡and¡¡to¡¡the¡¡west¡£

Anaxagoras¡¡as¡¡Meteorologist¡¡The¡¡man¡¡who¡¡had¡¡studied¡¡the¡¡meteorite¡¡of¡¡aegospotami£»¡¡and¡¡been¡¡put¡¡by¡¡it¡¡on¡¡the¡¡track¡¡of¡¡such¡¡remarkable¡¡inductions£»¡¡was£»¡¡naturally£»¡¡not¡¡oblivious¡¡to¡¡the¡¡other¡¡phenomena¡¡of¡¡the¡¡atmosphere¡£¡¡Indeed£»¡¡such¡¡a¡¡mind¡¡as¡¡that¡¡of¡¡Anaxagoras¡¡was¡¡sure¡¡to¡¡investigate¡¡all¡¡manner¡¡of¡¡natural¡¡phenomena£»¡¡and¡¡almost¡¡equally¡¡sure¡¡to¡¡throw¡¡new¡¡light¡¡on¡¡any¡¡subject¡¡that¡¡it¡¡investigated¡£¡¡Hence¡¡it¡¡is¡¡not¡¡surprising¡¡to¡¡find¡¡Anaxagoras¡¡credited¡¡with¡¡explaining¡¡the¡¡winds¡¡as¡¡due¡¡to¡¡the¡¡rarefactions¡¡of¡¡the¡¡atmosphere¡¡produced¡¡by¡¡the¡¡sun¡£¡¡This¡¡explanation¡¡gives¡¡Anaxagoras¡¡full¡¡right¡¡to¡¡be¡¡called¡¡¡¨the¡¡father¡¡of¡¡meteorology£»¡¨¡¡a¡¡title¡¡which£»¡¡it¡¡may¡¡be£»¡¡no¡¡one¡¡has¡¡thought¡¡of¡¡applying¡¡to¡¡him£»¡¡chiefly¡¡because¡¡the¡¡science¡¡of¡¡meteorology¡¡did¡¡not¡¡make¡¡its¡¡real¡¡beginnings¡¡until¡¡some¡¡twenty¡­four¡¡hundred¡¡years¡¡after¡¡the¡¡death¡¡of¡¡its¡¡first¡¡great¡¡votary¡£¡¡Not¡¡content¡¡with¡¡explaining¡¡the¡¡winds£»¡¡this¡¡prototype¡¡of¡¡Franklin¡¡turned¡¡his¡¡attention¡¡even¡¡to¡¡the¡¡tipper¡¡atmosphere¡£¡¡¡¨Thunder£»¡¨¡¡he¡¡is¡¡reputed¡¡to¡¡have¡¡said£»¡¡¡¨was¡¡produced¡¡by¡¡the¡¡collision¡¡of¡¡the¡¡clouds£»¡¡and¡¡lightning¡¡by¡¡the¡¡rubbing¡¡together¡¡of¡¡the¡¡clouds¡£¡¨¡¡We¡¡dare¡¡not¡¡go¡¡so¡¡far¡¡as¡¡to¡¡suggest¡¡that¡¡this¡¡implies¡¡an¡¡association¡¡in¡¡the¡¡mind¡¡of¡¡Anaxagoras¡¡between¡¡the¡¡friction¡¡of¡¡the¡¡clouds¡¡and¡¡the¡¡observed¡¡electrical¡¡effects¡¡generated¡¡by¡¡the¡¡friction¡¡of¡¡such¡¡a¡¡substance¡¡as¡¡amber¡£¡¡To¡¡make¡¡such¡¡a¡¡suggestion¡¡doubtless¡¡would¡¡be¡¡to¡¡fall¡¡victim¡¡to¡¡the¡¡old¡¡familiar¡¡propensity¡¡to¡¡read¡¡into¡¡Homer¡¡things¡¡that¡¡Homer¡¡never¡¡knew¡£¡¡Yet¡¡the¡¡significant¡¡fact¡¡remains¡¡that¡¡Anaxagoras¡¡ascribed¡¡to¡¡thunder¡¡and¡¡to¡¡lightning¡¡their¡¡true¡¡position¡¡as¡¡strictly¡¡natural¡¡phenomena¡£¡¡For¡¡him¡¡it¡¡was¡¡no¡¡god¡¡that¡¡menaced¡¡humanity¡¡with¡¡thundering¡¡voice¡¡and¡¡the¡¡flash¡¡of¡¡his¡¡divine¡¡fires¡¡from¡¡the¡¡clouds¡£¡¡Little¡¡wonder¡¡that¡¡the¡¡thinker¡¡whose¡¡science¡¡carried¡¡him¡¡to¡¡such¡¡scepticism¡¡as¡¡this¡¡should¡¡have¡¡felt¡¡the¡¡wrath¡¡of¡¡the¡¡superstitious¡¡Athenians¡£

Biological¡¡Speculations¡¡Passing¡¡from¡¡the¡¡phenomena¡¡of¡¡the¡¡air¡¡to¡¡those¡¡of¡¡the¡¡earth¡¡itself£»¡¡we¡¡learn¡¡that¡¡Anaxagoras¡¡explained¡¡an¡¡earthquake¡¡as¡¡being¡¡produced¡¡by¡¡the¡¡returning¡¡of¡¡air¡¡into¡¡the¡¡earth¡£¡¡We¡¡cannot¡¡be¡¡sure¡¡as¡¡to¡¡the¡¡exact¡¡meaning¡¡here£»¡¡though¡¡the¡¡idea¡¡that¡¡gases¡¡are¡¡imprisoned¡¡in¡¡the¡¡substance¡¡of¡¡the¡¡earth¡¡seems¡¡not¡¡far¡¡afield¡£¡¡But¡¡a¡¡far¡¡more¡¡remarkable¡¡insight¡¡than¡¡this¡¡would¡¡imply¡¡was¡¡shown¡¡by¡¡Anaxagoras¡¡when¡¡he¡¡asserted¡¡that¡¡a¡¡certain¡¡amount¡¡of¡¡air¡¡is¡¡contained¡¡in¡¡water£»¡¡and¡¡that¡¡fishes¡¡breathe¡¡this¡¡air¡£¡¡The¡¡passage¡¡of¡¡Aristotle¡¡in¡¡which¡¡this¡¡opinion¡¡is¡¡ascribed¡¡to¡¡Anaxagoras¡¡is¡¡of¡¡sufficient¡¡interest¡¡to¡¡be¡¡quoted¡¡at¡¡length£º¡¡¡¨Democritus£»¡¡of¡¡Abdera£»¡¨¡¡says¡¡Aristotle£»¡¡¡¨and¡¡some¡¡others£»¡¡that¡¡have¡¡spoken¡¡concerning¡¡respiration£»¡¡have¡¡determined¡¡nothing¡¡concerning¡¡other¡¡animals£»¡¡but¡¡seem¡¡to¡¡have¡¡supposed¡¡that¡¡all¡¡animals¡¡respire¡£¡¡But¡¡Anaxagoras¡¡and¡¡Diogenes¡¡£¨Apolloniates£©£»¡¡who¡¡say¡¡that¡¡all¡¡animals¡¡respire£»¡¡have¡¡also¡¡endeavored¡¡to¡¡explain¡¡how¡¡fishes£»¡¡and¡¡all¡¡those¡¡animals¡¡that¡¡have¡¡a¡¡hard£»¡¡rough¡¡shell£»¡¡such¡¡as¡¡oysters£»¡¡mussels£»¡¡etc¡££»¡¡respire¡£¡¡And¡¡Anaxagoras£»¡¡indeed£»¡¡says¡¡that¡¡fishes£»¡¡when¡¡they¡¡emit¡¡water¡¡through¡¡their¡¡gills£»¡¡attract¡¡air¡¡from¡¡the¡¡mouth¡¡to¡¡the¡¡vacuum¡¡in¡¡the¡¡viscera¡¡from¡¡the¡¡water¡¡which¡¡surrounds¡¡the¡¡mouth£»¡¡as¡¡if¡¡air¡¡was¡¡inherent¡¡in¡¡the¡¡water¡£¡¨£§2£§¡¡It¡¡should¡¡be¡¡recalled¡¡that¡¡of¡¡the¡¡three¡¡philosophers¡¡thus¡¡mentioned¡¡as¡¡contending¡¡that¡¡all¡¡animals¡¡respire£»¡¡Anaxagoras¡¡was¡¡the¡¡elder£»¡¡he£»¡¡therefore£»¡¡was¡¡presumably¡¡the¡¡originator¡¡of¡¡the¡¡idea¡£¡¡It¡¡will¡¡be¡¡observed£»¡¡too£»¡¡that¡¡Anaxagoras¡¡alone¡¡is¡¡held¡¡responsible¡¡for¡¡the¡¡idea¡¡that¡¡fishes¡¡respire¡¡air¡¡through¡¡their¡¡gills£»¡¡¡¨attracting¡¨¡¡it¡¡from¡¡the¡¡water¡£¡¡This¡¡certainly¡¡was¡¡one¡¡of¡¡the¡¡shrewdest¡¡physiological¡¡guesses¡¡of¡¡any¡¡age£»¡¡if¡¡it¡¡be¡¡regarded¡¡as¡¡a¡¡mere¡¡guess¡£¡¡With¡¡greater¡¡justice¡¡we¡¡might¡¡refer¡¡to¡¡it¡¡as¡¡a¡¡profound¡¡deduction¡¡from¡¡the¡¡principle¡¡of¡¡the¡¡uniformity¡¡of¡¡nature¡£¡¡In¡¡making¡¡such¡¡a¡¡deduction£»¡¡Anaxagoras¡¡was¡¡far¡¡in¡¡advance¡¡of¡¡his¡¡time¡¡as¡¡illustrated¡¡by¡¡the¡¡fact¡¡that¡¡Aristotle¡¡makes¡¡the¡¡citation¡¡we¡¡have¡¡just¡¡quoted¡¡merely¡¡to¡¡add¡¡that¡¡¡¨such¡¡things¡¡are¡¡impossible£»¡¨¡¡and¡¡to¡¡refute¡¡these¡¡¡¨impossible¡¨¡¡ideas¡¡by¡¡means¡¡of¡¡metaphysical¡¡reasonings¡¡that¡¡seemed¡¡demonstrative¡¡not¡¡merely¡¡to¡¡himself£»¡¡but¡¡to¡¡many¡¡generations¡¡of¡¡his¡¡followers¡£¡¡We¡¡are¡¡told¡¡that¡¡Anaxagoras¡¡alleged¡¡that¡¡all¡¡animals¡¡were¡¡originally¡¡generated¡¡out¡¡of¡¡moisture£»¡¡heat£»¡¡and¡¡earth¡¡particles¡£¡¡Just¡¡what¡¡opinion¡¡he¡¡held¡¡concerning¡¡man's¡¡development¡¡we¡¡are¡¡not¡¡informed¡£¡¡Yet¡¡there¡¡is¡¡one¡¡of¡¡his¡¡phrases¡¡which¡¡suggestswithout£»¡¡perhaps£»¡¡quite¡¡provingthat¡¡he¡¡was¡¡an¡¡evolutionist¡£¡¡This¡¡phrase¡¡asserts£»¡¡with¡¡insight¡¡that¡¡is¡¡fairly¡¡startling£»¡¡that¡¡man¡¡is¡¡the¡¡most¡¡intelligent¡¡of¡¡animals¡¡because¡¡he¡¡has¡¡hands¡£¡¡The¡¡man¡¡who¡¡could¡¡make¡¡that¡¡assertion¡¡must£»¡¡it¡¡would¡¡seem£»¡¡have¡¡had¡¡in¡¡mind¡¡the¡¡idea¡¡of¡¡the¡¡development¡¡of¡¡intelligence¡¡through¡¡the¡¡use¡¡of¡¡hands¡¡an¡¡idea¡¡the¡¡full¡¡force¡¡of¡¡which¡¡was¡¡not¡¡evident¡¡to¡¡subsequent¡¡generations¡¡of¡¡thinkers¡¡until¡¡the¡¡time¡¡of¡¡Darwin¡£

Physical¡¡Speculations¡¡Anaxagoras¡¡is¡¡cited¡¡by¡¡Aristotle¡¡as¡¡believing¡¡that¡¡¡¨plants¡¡are¡¡animals¡¡and¡¡feel¡¡pleasure¡¡and¡¡pain£»¡¡inferring¡¡this¡¡because¡¡they¡¡shed¡¡their¡¡leaves¡¡and¡¡let¡¡them¡¡grow¡¡again¡£¡¨¡¡The¡¡idea¡¡is¡¡fanciful£»¡¡yet¡¡it¡¡suggests¡¡again¡¡a¡¡truly¡¡philosophical¡¡conception¡¡of¡¡the¡¡unity¡¡of¡¡nature¡£¡¡The¡¡man¡¡who¡¡could¡¡conceive¡¡that¡¡idea¡¡was¡¡but¡¡little¡¡hampered¡¡by¡¡traditional¡¡conceptions¡£¡¡He¡¡was¡¡exercising¡¡a¡¡rare¡¡combination¡¡of¡¡the¡¡rigidly¡¡scientific¡¡spirit¡¡with¡¡the¡¡poetical¡¡imagination¡£¡¡He¡¡who¡¡possesses¡¡these¡¡gifts¡¡is¡¡sure¡¡not¡¡to¡¡stop¡¡in¡¡his¡¡questionings¡¡of¡¡nature¡¡until¡¡he¡¡has¡¡found¡¡some¡¡thinkable¡¡explanation¡¡of¡¡the¡¡character¡¡of¡¡matter¡¡itself¡£¡¡Anaxagoras¡¡found¡¡such¡¡an¡¡explanation£»¡¡and£»¡¡as¡¡good¡¡luck¡¡would¡¡have¡¡it£»¡¡that¡¡explanation¡¡has¡¡been¡¡preserved¡£¡¡Let¡¡us¡¡examine¡¡his¡¡reasoning¡¡in¡¡some¡¡detail¡£¡¡We¡¡have¡¡already¡¡referred¡¡to¡¡the¡¡claim¡¡alleged¡¡to¡¡have¡¡been¡¡made¡¡by¡¡Anaxagoras¡¡that¡¡snow¡¡is¡¡not¡¡really¡¡white£»¡¡but¡¡black¡£¡¡The¡¡philosopher¡¡explained¡¡his¡¡paradox£»¡¡we¡¡are¡¡told£»¡¡by¡¡asserting¡¡that¡¡snow¡¡is¡¡really¡¡water£»¡¡and¡¡that¡¡water¡¡is¡¡dark£»¡¡when¡¡viewed¡¡under¡¡proper¡¡conditionsas¡¡at¡¡the¡¡bottom¡¡of¡¡a¡¡well¡£¡¡That¡¡idea¡¡contains¡¡the¡¡germ¡¡of¡¡the¡¡Clazomenaean¡¡philosopher's¡¡conception¡¡of¡¡the¡¡nature¡¡of¡¡matter¡£¡¡Indeed£»¡¡it¡¡is¡¡not¡¡unlikely¡¡that¡¡this¡¡theory¡¡of¡¡matter¡¡grew¡¡out¡¡of¡¡his¡¡observation¡¡of¡¡the¡¡changing¡¡forms¡¡of¡¡water¡£¡¡He¡¡seems¡¡clearly¡¡to¡¡have¡¡grasped¡¡the¡¡idea¡¡that¡¡snow¡¡on¡¡the¡¡one¡¡hand£»¡¡and¡¡vapor¡¡on¡¡the¡¡other£»¡¡are¡¡of¡¡the¡¡same¡¡intimate¡¡substance¡¡as¡¡the¡¡water¡¡from¡¡which¡¡they¡¡are¡¡derived¡¡and¡¡into¡¡which¡¡they¡¡may¡¡be¡¡again¡¡transformed¡£¡¡The¡¡fact¡¡that¡¡steam¡¡and¡¡snow¡¡can¡¡be¡¡changed¡¡back¡¡into¡¡water£»¡¡and¡¡by¡¡simple¡¡manipulation¡¡cannot¡¡be¡¡changed¡¡into¡¡any¡¡other¡¡substance£»¡¡finds£»¡¡as¡¡we¡¡now¡¡believe£»¡¡its¡¡true¡¡explanation¡¡in¡¡the¡¡fact¡¡that¡¡the¡¡molecular¡¡structure£»¡¡as¡¡we¡¡phrase¡¡itthat¡¡is¡¡to¡¡say£»¡¡the¡¡ultimate¡¡particle¡¡of¡¡which¡¡water¡¡is¡¡composed£»¡¡is¡¡not¡¡changed£»¡¡and¡¡this¡¡is¡¡precisely¡¡the¡¡explanation¡¡which¡¡Anaxagoras¡¡gave¡¡of¡¡the¡¡same¡¡phenomena¡£¡¡For¡¡him¡¡the¡¡unit¡¡particle¡¡of¡¡water¡¡constituted¡¡an¡¡elementary¡¡body£»¡¡uncreated£»¡¡unchangeable£»¡¡indestructible¡£¡¡This¡¡particle£»¡¡in¡¡association¡¡with¡¡like¡¡particles£»¡¡constitutes¡¡the¡¡substance¡¡which¡¡we¡¡call¡¡water¡£¡¡The¡¡same¡¡particle¡¡in¡¡association¡¡with¡¡particles¡¡unlike¡¡itself£»¡¡might¡¡produce¡¡totally¡¡different¡¡substancesas£»¡¡for¡¡example£»¡¡when¡¡water¡¡is¡¡taken¡¡up¡¡by¡¡the¡¡roots¡¡of¡¡a¡¡plant¡¡and¡¡becomes£»¡¡seemingly£»¡¡a¡¡part¡¡of¡¡the¡¡substance¡¡of¡¡the¡¡plant¡£¡¡But¡¡whatever¡¡the¡¡changed¡¡association£»¡¡so¡¡Anaxagoras¡¡reasoned£»¡¡the¡¡ultimate¡¡particle¡¡of¡¡water¡¡remains¡¡a¡¡particle¡¡of¡¡water¡¡still¡£¡¡And¡¡what¡¡was¡¡true¡¡of¡¡water¡¡was¡¡true¡¡also£»¡¡so¡¡he¡¡conceived£»¡¡of¡¡every¡¡other¡¡substance¡£¡¡Gold£»¡¡s

·µ»ØĿ¼ ÉÏÒ»Ò³ ÏÂÒ»Ò³ »Øµ½¶¥²¿ ÔÞ£¨0£© ²È£¨0£©

Äã¿ÉÄÜϲ»¶µÄ