 of their simplicity. (Poincaré 1890, XII) In the preface to his Thermodynamics, Poincaré emphasizes the role that considerations of simplicity have in the construction of theories. Poincaré affirms that our mind is endowed with a faculty which is the condition of possibility of science: the faculty of generalizing the empirical data. It allows us to satisfy our need for order and harmony and at the same time allows us to foresee. The laws are formulated "after relatively few experiments and which present certain divergences". Since "every proposition can be generalized in an infinite number of ways", the choice of the general law is made according to our criterion of simplicity, by obeying "a necessity to which the human spirit cannot escape" (Poincaré 1892a, VI, VII). It is simplicity that favors the acceptance of the principles of thermodynamics: The imposing simplicity of the principle of Mayer [energy conservation] also contributes to affirm our faith in it. In a law deduced immediately from experience, such as that of Mariotte, this simplicity would appear to us rather a reason of mistrust, but here it is no longer the same, for we see elements, disparate at first glance, to be arranged in an unexpected order and to form a harmonious whole. (Poincaré 1892a, VIII) Poincaré also remarks the advantage of teaching the historical course of "long groping by which man arrives at the truth (...) We shall note the important role played by various theoretical or even metaphysical ideas" (Poincaré 1892a, V). Poincaré believes that the synchronic and diachronic comparison of theories allows the sedimentation of laws, which he will later call true relations [rapports vrais] (Poincaré 1900, 1168; 1902a, 292-3). Theories coordinate physical laws; for example, "the laws of optics and the equations which translate them analytically (...) will remain true, at least as a first approximation" (Poincaré 1889a, I-II), (Poincaré 1892b, VI). In his Thermodynamics he says: "The accuracy of physical laws is always limited by observation errors. But at least they pretend to be first approximations and we hope to replace them gradually by more and more precise laws" (Poincaré 1892a, XIII). Poincaré understands the complex nature of theories, which derives in large part from the multiplicity of inter-theoretical interrelationships, but he believes in the human capacity and need to reduce complexity in an unfore
of their simplicity. (Poincaré 1890, XII) In the preface to his Thermodynamics, Poincaré emphasizes the role that consideration of ease have in the construction of theories. Poincaré affirm that our mind is endowed with a staff which is the condition of possibility of science: the staff of popularize the empirical datum. It allows us to satisfy our need for order and harmony and at the like time allows us to anticipate. The laws are formulated " after relatively few experiment and which present certain divergences ". Since " every proposal can be generalized in an infinite number of ways ", the option of the general police is made according to our criterion of ease, by obeying " a necessity to which the human spirit cannot escape " (Poincaré 1892a, VI, VII). It is simplicity that favors the acceptance of the principles of thermodynamics: The imposing simplicity of the principle of Mayer [ energy conservation ] also contributes to affirm our faith in it. In a law deduced immediately from experience, such as that of Mariotte, this ease would appear to us rather a cause of misgiving, but here it is no longer the same, for we see elements, disparate at inaugural glance, to be arranged in an unexpected order and to form a harmonious whole. (Poincaré 1892a, VIII) Poincaré also note the advantage of teaching the historical course of " long groping by which man arrives at the accuracy (...) We shall note the important role played by various theoretical or even metaphysical ideas " (Poincaré 1892a, V). Poincaré believes that the synchronous and diachronic comparison of theory allows the sedimentation of laws, which he will later bid true relations [ rapports vrais ] (Poincaré 1900, 1168; 1902a, 292 - 3). Theories coordinate physical laws; for example, " the law of optics and the equality which translate them analytically (...) will remain truthful, at least as a first estimate " (Poincaré 1889a, I - II), (Poincaré 1892b, VI). In his Thermodynamics he says: " The accuracy of physical laws is always specify by observation errors. But at least they make to be first approximation and we hope to replace them gradually by more and more precise laws " (Poincaré 1892a, XIII). Poincaré understands the complex nature of theories, which derives in large part from the multiplicity of inter - theoretical interrelation, but he believes in the human capacity and necessitate to reduce complexity in an unfore
 of their simplicity. (Poincavé 1890, XII) In the prgfqce to his Tgermodynxmics, Poincaré emphasizes the rile tyat considerations of rimplicitj have in the xonstruction of thcjriea. Poiuceré affirms that our mind hs endowed witv x yaculty which is the condition of pofsibiliyy of science: thg faclley or generalizing the empirical data. Jt alloxs us to satisfu our need for order and hwrmojy and at the same time alloww us ro foresee. Tfe laws art yormulated "zfter relatively few experimentr and which prewebt fgrtain diverjences". Since "every proposidion cam be generalizcd in an infinite number of weys", the choice of thg general nac is made according ti iur ctiterhon ud skmpmiritg, by oheymng "a necesaity to whixh the human spirit cwbnot escape" (Pkincaré 1892a, VI, VII). It is simplicity that favors tht accsptance of the principlws of thermodynamics: Jhe imposigg simplicity of the principle of Mayer [energy cotservetkon] ajri fontributes to affirm our faith in it. In a lar dtdubed immediately fvom experience, sucn ws jhat of Mariotje, this sijplicity would appfar to os ratyer a reafon pf mistrust, but here it is bo longer thv sane, for we see elemznts, disparace at girst glance, to be arranged nn an hnexpected lrder and go form a harmonkoux fhole. (Poincaré 1892a, VIII) Poincwré also rxmarkx the aavanjage of teaching hhe hlvtorical course of "long gsoping by ahich man arrives at the truth (...) We shall note tve pmportant role played by vawious theoretieal or eren megaphysical ideas" ('oincaré 1892a, V). [oincaré belieegs that the sbnchronic and diaxhronic zomparison of yheories cjloww the sedimentatiok of uzws, which he wiol oater call true reuatyojs [rw[ports vrais] (Poivcafé 1900, 1168; 1902a, 292-3). Theoritf goofdinste physical laws; fos exzmple, "the laws of ppbics and jhe equatyons which trsnslate them analyuicallb (...) wilu remsin true, at least as a first apprkximation" (Polncaré 1889a, I-II), (Pjincqré 1892b, VI). In hns Thermodynamics he says: "The accuracy oh physical laws is alwats limited by obserrauion errors. Bnt at jeast thef pretend to be firsr approximations snd we hope to replacs them gradkally by more and more precise laws" (Poincaré 1892a, XIII). Poincaré understands thw complex nature or throriev, chieh derides mn large part from the multiplicity of inter-theorxtical intarxelationships, but he believes iv the human cxpacity and need to redude complrxity in an unfore
of their simplicity. (Poincaré 1890, XII) In to Thermodynamics, Poincaré the role that the of theories. Poincaré that our mind endowed with a faculty which is condition of possibility of science: the faculty of generalizing the empirical data. It us to satisfy our need for order and harmony and at the same allows to The are formulated "after relatively few experiments and which present certain divergences". Since "every proposition can be in an infinite number of ways", the choice the general law is according to our criterion of by "a necessity which human cannot escape" (Poincaré VI, VII). It is simplicity that favors the acceptance of the principles of thermodynamics: The imposing simplicity the principle [energy conservation] contributes affirm faith in it. law deduced immediately from experience, such Mariotte, this simplicity would appear to us rather reason of but here it is no longer same, for we see elements, disparate at first to be arranged in an unexpected order and to form a harmonious whole. (Poincaré 1892a, also remarks the advantage teaching the historical of groping which arrives at truth (...) We shall note the important role played by various or even metaphysical ideas" (Poincaré 1892a, V). Poincaré believes that and comparison of theories the sedimentation of laws, he later call true relations (Poincaré 1168; coordinate laws; example, "the laws of and the equations which translate analytically (...) will remain first approximation" (Poincaré 1889a, I-II), (Poincaré 1892b, VI). his Thermodynamics he says: "The accuracy of laws is always limited by observation errors. But at least they pretend be first we hope to replace them gradually by more more precise laws" (Poincaré XIII). Poincaré understands the complex nature of theories, which in part from multiplicity of inter-theoretical but he believes the human capacity to reduce in unfore
 of their simplicity. (Poincaré 1890, xII) In the prEface To hIs THeRmodYnamIcs, Poincaré empHAsizEs the role that consideraTions Of SImplICiTy havE in the cONsTRUctIoN oF thEoRIeS. PoinCarÉ affirmS that our miNd iS eNdowed with a fACuLty which is The Condition of pOssIbilitY oF scIEnce: tHe fAcultY of genERaliziNg the empiRiCAl data. iT allows US To SatiSfy our need for ordeR AnD Harmony and at thE same tImE AlLOWs uS to Foresee. The LaWs are FOrmulatED "aFTER reLAtively few expEriments and WHicH preseNt CerTAin divErgenCeS". sinCe "every propOsitIon can be gEneralIZed in an INfinite Number Of wAys", The cHOiCe Of tHe GEneRAl Law IS maDe accordInG tO our cRiteRION Of siMplIcitY, by obEying "a necessiTy tO whiCH thE humaN spirIt caNnOt escApe" (PoiNcaré 1892A, Vi, VII). It is simplicIty tHat favors The AcCepTaNce of THe prinCipLes Of thermOdynamiCS: ThE iMPOSiNg simplicity of the pRiNCIpLe of MayeR [energY CoNsERvation] aLsO coNtriBUTes to AffiRM oUr faith iN it. In a LAw DeDuced imMeDiatelY fRom ExpErienCE, sucH as thaT of MarioTte, thIS simplicity wouLD appear to us raTHeR A ReASon oF miStrust, but heRe it IS no lOngeR ThE saME, for wE see eLeMEnTS, disparate at first glAnCe, to be ArranGed in an unexpeCted order aND TO form a haRmonIOuS Whole. (Poincaré 1892a, vIII) POincaré alsO Remarks tHe advAntage of Teaching tHE HistoricAl cOurSe oF "loNG GrOping by which mAN ArriVeS at the tRutH (...) We shalL noTe tHe iMpoRtAnt role plAyed by vaRiOuS tHeOreTical OR even metApHysIcAl iDeas" (POIncaré 1892A, V). PoiNcarÉ bElIEveS that thE SyNCHronIc AnD diaChrOnIc comPariSOn oF theoriEs allows tHe sEDimeNtAtIon of laWs, which he will LaTer call truE rElaTions [rAPPorts vraIs] (Poincaré 1900, 1168; 1902a, 292-3). Theories coorDInate phYsiCal laWs; foR example, "tHe lAws of oPtiCS and thE equatIons wHiCh tRANslatE THeM anAlYtically (...) wiLL RemAin trUe, At leAst as a fIrst approximation" (POIncAré 1889a, I-II), (PoincaRé 1892b, vI). In HIS THerMOdYNamIcS He sAYS: "The accuracy of pHysical lawS iS AlWays limiteD By oBsErvatioN errors. but at LEast theY pretend tO be first aPpRoxiMATioNs and we hopE to replaCe them graDUally BY mOre anD moRe precIsE laWs" (PoiNcaré 1892a, xiII). poincAré undErStands The coMpLex naturE of theories, which derives In largE part FroM the multiPliCIty Of inter-thEoreTical interRelAtiOnshiPs, bUT he beLievES iN thE Human CapaCIty and neeD To RedUCE cOmplexity in AN UNfoRe
 of their simplicity. (Poi ncaré 1890 , XII ) I n t he  pre face  to his Thermo d ynam ics, Poincaré emphasiz es th er olet ha t con siderat i on s ofsi mp lic it y  h ave i n t he cons truction o f t he ories. Poinc a ré  affirms t hat  our mind is  en dowedwi tha  facu lty  whic h is t h e cond ition ofpo s sibili t y of sc i e nc e: t he faculty of gen e ra l izing the empi ricalda t a. I t a llo ws us to s at isfyo ur need fo r o rde r  and harmonyand at thes ame  timeal low s  us to  fore se e . T he laws are  for mulated " afterr elative l y few e xperim ent s a nd w h ic hpre se n t c e rt ain div ergences ".  S ince"eve r y p ropo sit ioncan b e generalized  in  ani nfi nitenumbe r of  w ays",  the c hoice  o f the general l aw i s made ac cor di ngto  ourc riteri onofsimplic ity, by obe yi n g "a  necessity to whic ht h ehuman sp irit c a nn ot escape"(P oin caré 1 892a,  VI, VI I). It i s simp l ic it y thatfa vors t he  ac cep tance of t he pri nciplesof th e rmodynamics: T h e imposing si m pl i c it y  ofthe  principleof M a yer[ene r gy  co n serva tion]  a l so contributes to affi rm  our f aithin it. In a l aw deduced i m mediatel y fr o me xperience, suc h asthat of Ma r iotte, t his s implicit y would a p p ear to u s r ath era r e a so n of mistrust , buthe re it i s n o longe r t hesam e,fo r we seeelements ,di sp ar ate  at f i rst glan ce , t obearran g ed inan un expe ct ed ord er andt of o rm a  h ar moni ous  w hole.  (Po i nca ré 1892 a, VIII)Poi n caré  a ls o remar ks the advant ag e of teach in g t he his t o rical co urse of "long groping b y  whichman  arri vesat the tr uth  (...)  We shallnote t he im po rta n t  role p la yed  b y varioust h eor etica lor e ven met aphysical ideas" ( P oin caré 1892a, V ).Poin c a ré  be l ie v esth a t t h e  synchronic and  diachroni cc om parison of the or ies all ows the  sedi m entatio n of laws , which h ewill l ate r call tru e relati ons [rapp o rts v r ai s] (P oin caré 1 90 0,1168;  1902a ,  29 2-3).  Theor ie s coor dinat ephysical  laws; for example, "th e laws  of o pti cs and th e e q uat ions whic h tr anslate th emana lytic all y  (... ) wi l lrem a in tr ue,a t least a s  a  fi r s tapproximati o n "  (P oinca ré1 889a,I-II ), (Poincaré 1892 b , VI). In hisTher m o dyn ami c s he  s ays: "The accu rac yo f  physica llaws is alw ays limi te d  by o bserva tion e rrors.B u ta t leas t th eypretend t o b ef irst ap pr ox i mation s an dwe hop e to r e plac e them gradually b y mor e and m o repreci se  laws"( Poin caré 1892a , XIII). Po incaré  und ersta nds the  c omplex  na tu re of theo r ies, whic h der ives in  l arge  pa rt fro m th e multi plic it y o f inter-t h e or e ti ca l  in terr elati on ship s, but he believes  in the hum an  ca p a city a n dn e ed to redu cecompl e x ity in anu nfor e 
 of_their simplicity._(Poincaré 1890, XII) In_the preface_to_his Thermodynamics,_Poincaré_emphasizes the role_that considerations of_simplicity have in the_construction of theories._Poincaré_affirms that our mind is endowed with a faculty which is the condition of_possibility_of science:_the_faculty_of generalizing the empirical data._It allows us to satisfy_our need_for order and harmony and at the same_time_allows us to_foresee. The laws are formulated "after relatively few experiments_and which present certain divergences". Since_"every proposition can_be_generalized_in an infinite number_of ways", the choice of the_general law is made according to_our criterion of simplicity, by obeying "a_necessity to which the human spirit_cannot escape" (Poincaré 1892a, VI,_VII). It_is simplicity that favors the_acceptance of the_principles of_thermodynamics: The imposing_simplicity of the principle of Mayer_[energy conservation] also_contributes to affirm our faith in_it._In a law_deduced_immediately_from experience,_such as that_of_Mariotte, this_simplicity_would appear to us rather a_reason_of mistrust, but here it is no_longer the same, for_we_see elements, disparate at_first glance, to be arranged_in an unexpected order and to_form a_harmonious whole._(Poincaré 1892a, VIII) Poincaré also remarks the advantage of teaching the_historical course of "long groping by_which man arrives at_the truth_(...)_We shall note_the_important role_played by various theoretical or even metaphysical_ideas" (Poincaré_1892a, V). Poincaré believes that the_synchronic and diachronic comparison_of_theories allows the sedimentation of laws,_which he will later call true_relations [rapports vrais] (Poincaré 1900,_1168;_1902a,_292-3). Theories coordinate physical laws;_for example, "the laws of optics_and the equations_which translate them analytically (...) will remain_true,_at least as a first approximation"_(Poincaré_1889a, I-II), (Poincaré 1892b, VI). In_his_Thermodynamics_he says: "The accuracy of_physical laws is always limited by_observation errors. But at least they pretend to be_first approximations and_we hope to replace them_gradually_by_more and more precise laws" (Poincaré 1892a, XIII). Poincaré understands_the complex_nature of theories,_which derives in large part from the multiplicity of inter-theoretical_interrelationships, but he believes in the human_capacity and need to reduce complexity in an unfore