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1、ACONCISETEXTBOOKOFAGRICULTURALENGLISHUNIT1FUNDAMENTALMETHODSINLIFESCIENCEHowisitthatscientistsprobesoskillfullyintothemonumentoflifeanddiscoversomuchaboutitsfoundations?Whatisitabouttheirmannerofthinkingthatyieldssuchpreciseresults?Thescientificmethodisaformalizedwayofansweringqu
2、estionsaboutcausationinthenaturalworld.Inprinciple,thescientificmethodhasthreemainsteps(althoughinpracticescientistsworkinmanydifferentways).Thefirststepistocollectobservations,phenomenawhichcanbedetectedbythesenses(vision,hearing,smell,taste,andtouch).Observationscanbealsomadein
3、directly,throughuseofspecialequipment(suchasamicroscope)thatextendedtherangeofperception.Withpractice,wecanbecomeskilledatmakingsystematicobservations.Thismeansfocusingoneormoresensesonaparticularobjectoreventintheenvironment,andscreeningoutthe“backgroundnoise”ofinformationthatpr
4、obablyhasnobearingonourfocus.Second,thescientistthinksofhypothesis,ideasaboutthecauseofwhathasbeenobserved.Thethirdstepisexperimentation,performingtestsdesignedtoshowthatoneormoreofthehypothesisismoreorlesslikelytobeincorrect.Hypothesizingmeansputtingtogetheratentativeexplanation
5、toaccountforanobservation.Noscientistcanputforwardanideaanddemandthatitbebelievedastrue,noquestionsasked.Inscience,therearenoabsolutetruths.Thereareonlyhighprobabilitiesthatanideaiscorrectinthecontextofobservationsandtestsmadesofar.Insteadofabsolutes,thereissuspendedjudgment.This
6、meansahypothesisistentativelysaidtobevalidifitisconsistentwithobservationsathand.Youwon’t(orshouldn’t)hearascientistsay,“thereisnootherexplanation!”Morelikelyyouwillhear,“Basedonpresentknowledge,thisexplanationisourbestjudgmentatthemoment.”Oftentheweightofevidenceissoconvincingth
7、atthehypothesisbecomesacceptedasatheory:acoherentsetofideasthatformageneralframeofreferenceforfurtherstudies.Inscience,theword“theory”isnotusedlightly.Itisbestowedonlyonhypothesisthatcanberelieduponwithaveryhighdegreeofconfidence.Testingthehypothesisthroughexperimentsisattheheart
8、ofscientificinquiry.Experimentsmustbedes