 substitution can be obtained either by a more continuous process, which maintains the hypotheses of the first theory by adding new parameters or some new hypotheses; or by a process which requires deeper modifications "which alter the definitions and assumptions upon which the first theory was based" (Duhem 1892a, 152). According to the preceding considerations, the value of a theory depends on the examination of the extent of the domain of a theory, of experimental uncertainty, and of the concrete use of a theory (its more immediate instrumental character). Duhem proposes other more internal/logical criteria to make the choice between competing theories: Logic leaves the choice of hypotheses free; but it requires that all these hypotheses be compatible among themselves, that they are all independent of one another; a theory has no right to invoke unnecessary assumptions; it must reduce its number to a minimum; it has no right to bring together consequences deduced from irreconcilable assumptions. (Duhem 1892a, 166; see also 169) Until now, Duhem, in his overview of the criteria for evaluating the value of a theory, remains in the consensual plan of a certain good sense, as long as we accepts the central role of hypotheses and of the convenient definitions needed for measurement. This plan is abandoned when Duhem judges contemporary theories. Firstly, after citing the passage of Poincaré on the French style of presentation of the theories (see above), Duhem sees a weakness of the mind in the style of the Treatise of Maxwell (Duhem 1892a, 168), which implies a mixture of irreconcilable hypotheses -a subject developed in a subsequent text on the English School (Duhem 1893); in the latter text, among his long considerations, Duhem does not tell us his opinion on what Poincaré considered the fundamental idea of Maxwell's Treatise, most probably because it is in harmony with the research program of Duhem: the Lagrangian approach valorizes a phenomenalist 16 There is a passage in which Duhem alludes to Helmholtz's considerations on non-Euclidean geometries (Poincaré refers them to the end of his article of 1891) and on arithmetic and the problem of measurement: "these profound researches on foundations of geometry and these meditations, so satisfying to the mind, concerning the origin of the axioms of arithmetic" [reference to Zahlen und messen, published in 1887] (Duhem 1893, 375). 17 I am the one who emphasizes. Experimental control is not therefore a simple and immediate action. In the Commentary, considering "absolute
substitution can be obtained either by a more continuous process, which maintains the hypotheses of the inaugural hypothesis by adding new argument or some raw hypotheses; or by a process which want deep modifications " which change the definitions and assumptions upon which the beginning theory was based " (Duhem 1892a, 152). accord to the precede considerations, the value of a hypothesis depends on the interrogation of the extent of the sphere of a theory, of experimental uncertainty, and of the concrete use of a hypothesis (its more immediate instrumental fictional character). Duhem proposes early more internal / coherent criteria to make the choice between compete theories: Logic leaves the choice of hypotheses free; but it requires that all these hypotheses be compatible among themselves, that they are all independent of one another; a theory has no right to invoke unnecessary assumptions; it must reduce its number to a minimum; it has no right field to institute together consequence deduced from irreconcilable assumptions. (Duhem 1892a, 166; see also 169) Until nowadays, Duhem, in his overview of the criteria for evaluating the value of a theory, remains in the consensual design of a certain good sense, as long as we accepts the central role of hypotheses and of the convenient definitions needed for measurement. This plan is abandon when Duhem judge contemporary theories. Firstly, after citing the passage of Poincaré on the French stylus of presentation of the theories (see above), Duhem sees a weakness of the mind in the style of the Treatise of Maxwell (Duhem 1892a, 168), which implies a mix of irreconcilable hypotheses -a topic developed in a subsequent text on the English School (Duhem 1893); in the latter textbook, among his long considerations, Duhem does not tell us his opinion on what Poincaré consider the fundamental theme of Maxwell's Treatise, most probably because it is in harmony with the inquiry program of Duhem: the Lagrangian approach valorizes a phenomenalist 16 There is a passage in which Duhem alludes to Helmholtz's considerations on non - Euclidean geometries (Poincaré refers them to the end of his article of 1891) and on arithmetic and the problem of measurement: " these fundamental researches on foundations of geometry and these meditation, so satisfying to the thinker, concerning the origin of the axioms of arithmetical " [ reference to Zahlen und messen, published in 1887 ] (Duhem 1893, 375). 17 I am the one who emphasizes. Experimental control is not therefore a simple and immediate action. In the Commentary, think " absolute
 suhstitution can be obtaintd either by a mote contiiuous pdocess, wfich maintains the hypothesed if tht first theory by aading new parametwrs ie some new hypotheses; or ny a 'ricess which reauires dee[er modificatimnr "chich alter the definitions and assuiptions uoon which the sirsu treorg was based" (Duhem 1892a, 152). According to fhe prebeding consideratoons, the value of a theory depfnds on the examinwtion of thg exewnt of the dumain of a theory, of esperimental uncertainty, and of ghe cpncrete usg kf d theory (itw morv immediate ikxtrumettal chsracter). Duhem iropoves other more internal/lmgical criteria to make the ckoice between competibg theoties: Nogiz lexvea vhe choicf oh hypothesea free; but ut requires that alk eyese hypothesss be soipatible among themselves, that they are alm independent of one anither; a theory has no right to invoke unnecessary assumptions; it must reduce itv numuef ti w nijimum; it has no right to bring together consezhemcvs deduced from ivreconcilable assukphipgs. (Duhem 1892a, 166; sge also 169) Uhtil now, Duhem, in jis ovetview if the cryteroa for evaluating the value of a theory, eemains in the condensual plau of a certsin good sense, as long cs we zccepts the central dule of hypotheser akd mf the convenient definitijns needev for measurdmenj. This [lan is abwndoncg when Duhem judged conjempordry theorifs. Firstly, after citing the passage of Poincaté ot tve Frenck stylc of presentatijn of the theoties (see cbove), Auhem sees a weakiess of the iind in the sdile of the Trxatise of Maxqell (Duhem 1892x, 168), which impliex a mixtuge of urreconcilable hyppthgsss -a subject dertlokee in a subsequrnt tevt oi the Anglish Schoml (Djheo 1893); in ghe latuzr bexg, ampng his long considesatikns, Duhem does not tcll us hiw opiniog on what Poimcaré considered tht fundementau ides os Maxwell's Treatise, most probagly becaude lt is in harmjny qith the reszarch program of Duhem: the Lagrangian ap'roach valorizes a phenimenalist 16 There is s passage ii whicr Duhem anludes to Helmholtz's considerations ok non-Euclidean geometrjes (Pohncaré refers them to the end of his article of 1891) and on arithmetic and the proboem of measurement: "thexe prmfjbnd resqarcier on foundations of geometry and these meditatiuns, so sdtnsfying to the mind, concerninb ghe origin of the axioms of arithmetid" [referemce to Zahlen und messen, publisned in 1887] (Duhem 1893, 375). 17 I am thc one who emphzsizes. Expxrimental control is not tkerefoee a sinple and immediatd avtlon. In the Comkeutary, considering "absolute
substitution can be obtained either by a process, maintains the of the first or new hypotheses; or a process which deeper modifications "which alter the definitions assumptions upon which the first theory was based" (Duhem 1892a, 152). According to preceding considerations, the value of a theory depends on the examination of the of domain a of experimental uncertainty, and of the concrete use of a theory (its more immediate instrumental character). proposes other more internal/logical criteria to make the between competing theories: Logic the choice of hypotheses free; it that all hypotheses compatible themselves, that they all independent of one another; a theory has no right to invoke unnecessary assumptions; it must reduce number to it has right bring consequences deduced from (Duhem 1892a, 166; see also 169) in his overview of the criteria for evaluating value of theory, remains in the consensual plan a certain good sense, as long as we the central role of hypotheses and of the convenient definitions needed for measurement. This plan when Duhem judges contemporary Firstly, after citing passage Poincaré the style of of the theories (see above), Duhem sees a weakness of the in the style of the Treatise of Maxwell (Duhem 1892a, implies mixture of irreconcilable -a subject developed in subsequent on the English School in latter long Duhem not tell us his on what Poincaré considered the idea of Maxwell's Treatise, in harmony with the research program of Duhem: Lagrangian approach valorizes a phenomenalist 16 There a passage in which Duhem alludes to Helmholtz's considerations on non-Euclidean geometries refers them end of his article of 1891) and on and the problem of "these profound researches on foundations of geometry and these so to the concerning the origin the axioms of [reference to Zahlen published in (Duhem 375). the one who emphasizes. Experimental control not a simple and immediate action. the "absolute
 substitution can be obtained Either by a mOre coNtiNuoUs ProcEss, wHich maintains tHE hypOtheses of the first theorY by adDiNG new PArAmeteRs or somE NeW HYpoThEsEs; oR bY A pRocesS whIch requIres deeper ModIfIcations "whicH AlTer the defiNitIons and assumPtiOns upoN wHicH The fiRst TheorY was baSEd" (DuheM 1892a, 152). AccordiNg TO the prECeding cONSiDeraTions, the value of a tHEoRY depends on the eXaminaTiON oF THe eXteNt of the domAiN of a tHEory, of eXPeRIMEntAL uncertainty, aNd of the concREte Use of a ThEorY (Its morE immeDiATe iNstrumental CharActer). DuheM propoSEs other MOre inteRnal/loGicAl cRiteRIa To MakE tHE chOIcE beTWeeN competiNg ThEorieS: LogIC LEAves The ChoiCe of hYpotheses free; But It reQUirEs thaT all tHese HyPotheSes be cOmpatIbLe among themselvEs, thAt they are All InDepEnDent oF One anoTheR; a tHeory haS no righT To iNvOKE UnNecessary assumptioNs; IT MuSt reduce Its numBEr To A Minimum; iT hAs nO rigHT To briNg toGEtHer conseQuenceS DeDuCed from IrReconcIlAblE asSumptIOns. (DUhem 1892a, 166; sEe also 169) UnTil noW, duhem, in his overVIew of the criteRIa FOR eVAluaTinG the value of A theORy, reMainS In The COnsenSual pLaN Of A Certain good sense, as lOnG as we aCceptS the central roLe of hypothESES and of thE conVEnIEnt definitions NeedeD for measurEMent. This Plan iS abandonEd when DuhEM Judges coNteMpoRarY thEORiEs. Firstly, afteR CItinG tHe passaGe oF PoincaRé oN thE FrEncH sTyle of preSentatioN oF tHe ThEorIes (seE Above), DuhEm SeeS a WeaKness OF the miNd in tHe stYlE oF The treatisE Of mAXwelL (DUhEm 1892a, 168), wHicH iMplieS a miXTurE of irreConcilablE hyPOtheSeS -a Subject Developed in a sUbSequent texT oN thE EngliSH school (DuHem 1893); in the latter text, among HIs long cOnsIderaTionS, Duhem doeS noT tell uS hiS OpinioN on whaT PoinCaRé cONSiderED ThE fuNdAmental ideA OF MaXwell'S TReatIse, most Probably because it iS In hArmony with the ResEarcH PRoGraM Of dUheM: tHE LaGRAngian approach vAlorizes a pHeNOmEnalist 16 TheRE is A pAssage iN which DUhem aLLudes to helmholtz'S considerAtIons ON Non-euclidean gEometrieS (Poincaré REfers THeM to thE enD of his ArTicLe of 1891) aNd on arIThmEtic aNd the pRoBlem of MeasuReMent: "thesE profound researches on foUndatiOns of GeoMetry and tHesE MedItations, sO satIsfying to tHe mInd, ConceRniNG the oRigiN Of The AXioms Of arIThmetic" [reFErEncE TO ZAhlen und mesSEN, PubLisheD in 1887] (dUhem 1893, 375). 17 I aM the One who emphasizes. EXPerimental contRol iS NOt tHerEFore A sImple and immediAte AcTIOn. In the COmMentary, consIdering "aBsOLute
 substitution can be obtai ned either  by a  mo reco ntin uous  process, whic h  mai ntains the hypothesesof th ef irst th eoryby addi n gn e w p ar am ete rs or  some  ne w hypot heses; orbyaprocess whic h  r equires de epe r modificati ons  "whic halt e r the  de finit ions a n d assu mptions u po n  which the fir s t  t heor y was based" (Duh e m1 892a, 152). Ac cordin gt ot h e p rec eding cons id erati o ns, the va l u e  of a theory depe nds on thee xam inatio noft he ext ent o ft hedomain of a  the ory, of e xperim e ntal un c ertaint y, and  of  th e co n cr et e u se ofa  t heo r y ( its more  i mm ediat e in s t r u ment alchar acter ). Duhem prop ose s ot h ermoreinter nal/ lo gical  crite ria t omake the choice  bet ween comp eti ng  th eo ries: Logiclea ves  the ch oice of hyp ot h e s es  free; but it requ ir e s  t hat alltheseh yp ot h eses beco mpa tibl e among  the m se lves, th at the y  a re  all in de penden tofone  anot h er;a theo ry has n o rig h t to invoke un n ecessary assu m pt i o ns ;  itmus t reduce it s nu m berto a mi nim u m; it  hasno ri g ht to bring togethe rconseq uence s deduced fro m irreconc i l a ble assu mpti o ns .  (Duhem 1892a,  166;  see also1 69) Unti l now , Duhem,  in his o v e rview of  th e c rit eri a fo r evaluatingt h e va lu e of athe ory, re mai nsinthe  c onsensual  plan of  a  c er ta ingoods ense, as  l ong  a s w e acc e pts th e cen tral  r ol e  of  hypoth e se s andof  t he c onv en ientdefi n iti ons nee ded for m eas u reme nt .This pl an is abandon ed  when Duhe mjud ges co n t emporary  theories. Firstly, aft e r citin g t he pa ssag e of Poin car é on t heF renchstyleof pr es ent a t ion o f th e t he ories (see a bov e), D uh em s ees a w eakness of the min d  in  the style of  th e Tr e a ti seo fM axw el l  (D u h em 1892a, 168),  which imp li e sa mixtureo f i rr econcil able hy pothe s es -a s ubject de veloped i na su b s equ ent text o n the En glish Sch o ol (D u he m 189 3);  in th elat ter t ext, a m ong  hislong c on sidera tions ,Duhem do es not tell us his opin ion on  what  Po incaré co nsi d ere d the fun dame ntal ideaofMax well' s T r eatis e, m o st  pr o bably  bec a use it is in  ha r m on y with ther e s ear ch pr ogr a m of D uhem : the Lagrangiana pproach valori zesa phe nom e nali st  16 There is a  pa ss a g e in whi ch  Duhem allu des to H el m holtz 's con sidera tions o n no n -Eucli dean  ge ometries(Po in c aré ref er st hem to  the  e nd ofhis ar t icle o f 1891) and on a rithm e t ic an d  th e pro bl em of m e asur ement: "th ese profoun d rese arch es on  founda ti ons of  ge om etry and t h ese medit ation s, so s at isfy ing  to th e mi n d , con cern in g t he origin o ft he  a x iom s of  arit hm etic " [refere n ce to Za hle n  und me ss en, p ublish e di n  1887] (Du hem  1893 , 375). 17 I am t h eo ne wh o emph asizes . Exper i men ta l contr oli s  not ther efore a s i mpl eandimmediat eacti on . I nthe Commentary,  conside ring "ab s o lute
 substitution_can be_obtained either by a_more continuous_process,_which maintains_the_hypotheses of the_first theory by_adding new parameters or_some new hypotheses;_or_by a process which requires deeper modifications "which alter the definitions and assumptions upon_which_the first_theory_was_based" (Duhem 1892a, 152). According_to the preceding considerations, the_value of_a theory depends on the examination of the_extent_of the domain_of a theory, of experimental uncertainty, and of the_concrete use of a theory (its_more immediate instrumental_character)._Duhem_proposes other more internal/logical_criteria to make the choice between_competing theories: Logic leaves the choice_of hypotheses free; but it requires that_all these hypotheses be compatible among_themselves, that they are all_independent of_one another; a theory has_no right to_invoke unnecessary_assumptions; it must_reduce its number to a minimum;_it has no_right to bring together consequences deduced_from_irreconcilable assumptions. (Duhem_1892a,_166;_see also_169) Until now,_Duhem,_in his_overview_of the criteria for evaluating the_value_of a theory, remains in the consensual_plan of a certain_good_sense, as long as_we accepts the central role_of hypotheses and of the convenient_definitions needed_for measurement._This plan is abandoned when Duhem judges contemporary theories. Firstly, after_citing the passage of Poincaré on_the French style of_presentation of_the_theories (see above),_Duhem_sees a_weakness of the mind in the style_of the_Treatise of Maxwell (Duhem 1892a, 168),_which implies a mixture_of_irreconcilable hypotheses -a subject developed in_a subsequent text on the English_School (Duhem 1893); in the_latter_text,_among his long considerations, Duhem_does not tell us his opinion_on what Poincaré_considered the fundamental idea of Maxwell's Treatise,_most_probably because it is in harmony_with_the research program of Duhem: the_Lagrangian_approach_valorizes a phenomenalist 16 There_is a passage in which Duhem_alludes to Helmholtz's considerations on non-Euclidean geometries (Poincaré refers_them to the_end of his article of_1891)_and_on arithmetic and the problem of measurement: "these profound researches_on foundations_of geometry and_these meditations, so satisfying to the mind, concerning the origin_of the axioms of arithmetic" [reference to_Zahlen und messen, published in 1887] (Duhem 1893, 375). 17 I_am the one who emphasizes. Experimental control is_not therefore a simple and immediate action._In the Commentary, considering_"absolute